WorldWideScience

Sample records for 120-to-200 ghz frequency

  1. A CMOS frequency generation module for 60-GHz applications

    Institute of Scientific and Technical Information of China (English)

    Zhou Chunyuan; Zhang Lei; Wang Hongrui; Qian He

    2012-01-01

    A frequency generation module for 60-GHz transceivers and phased array systems is presented in this paper.It is composed of a divide-by-2 current mode logic divider (CM L) and a doubler in push-push configuration.Benefiting from the CML structure and push-push configuration,the proposed frequency generation module has a wide operating frequency range to cover process,voltage,and temperature variation.It is implemented in a 90-nm CMOS process,and occupies a chip area of 0.64 × 0.65 mm2 including pads.The measurement results show that the designed frequency generation module functions properly with input frequency over 15 GHz to 25 GHz.The whole chip dissipates 12.1 mW from a 1.2-V supply excluding the output buffers.

  2. Long term variability of radio sources in the frequencies of 22 GHz and 44 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Botti, L.C.L.; Abraham, Z.

    1987-05-01

    The radio sources 3C273, OV236, Cen A and Sgr A were observed during a period of six years (1980-1986), in the frequencies of 22 GHz and 44 GHz, with the Itapetinga radiotelescope (Brazil). The objective of this work was the detection of variability in the intensity and in the shape of the spectra of the sources. All of them presented some variability, specially the quasar 3C273, which after a period of intense activity (1981-1985), returned to its quiescent level at the end of 1985. The increase of the flux density in these frequencies is associated to the ejection of new components by the central source in the quasar, as observed in the maps obtained by VLBI techniques. 17 references, 4 figures.

  3. Design of tunable GHz-frequency optomechanical crystal resonators

    CERN Document Server

    Pfeifer, Hannes; Zang, Leyun; Painter, Oskar

    2016-01-01

    We present a silicon optomechanical nanobeam design with a dynamically tunable acoustic mode at 10.2 GHz. The resonance frequency can be shifted by 90 kHz/V^2 with an on-chip capacitor that was optimized to exert forces up to 1 $\\mu$N at 10 V operation voltage. Optical resonance frequencies around 190 THz with Q factors up to $2.2 \\times 10^6$ place the structure in the well-resolved sideband regime with vacuum optomechanical coupling rates up to $g_0/2\\pi = 353$ kHz. Tuning can be used, for instance, to overcome variation in the device-to-device acoustic resonance frequency due to fabrication errors, paving the way for optomechanical circuits consisting of arrays of optomechanical cavities.

  4. Measurement of the dielectric properties of the epidermis and dermis at frequencies from 0.5 GHz to 110 GHz

    Science.gov (United States)

    Sasaki, K.; Wake, K.; Watanabe, S.

    2014-08-01

    Numerous studies have reported the measurements of the dielectric properties of the skin. Clarifying the manner in which the human body interacts with electromagnetic waves is essential for medical research and development, as well as for the safety assessment of electromagnetic wave exposure. The skin comprises several layers: the epidermis, the dermis, and the subcutaneous fat. Each of these skin layers has a different constitution; however, the previous measurements of their dielectric properties were typically conducted on tissue which included all three layers of the skin. This study presents novel dielectric property data for the epidermis and dermis with in vitro measurement at frequencies ranging from 0.5 GHz to 110 GHz. Measured data was compared with literature values; in particular, the findings were compared with Gabriel’s widely used data on skin dielectric properties. The experimental results agreed with the data reported by Gabriel for the dermis of up to 20 GHz, which is the upper limit of the range of frequencies at which Gabriel reported measurements. For frequencies of 20-100 GHz, the experimental results indicated larger values than those extrapolated from Gabriel’s data using parametric expansion. For frequencies over 20 GHz, the dielectric properties provided by the parametric model tend toward the experimental results for the epidermis with increasing frequency.

  5. Design and modeling of inductors, capacitors and coplanar waveguides at tens of GHz frequencies

    CERN Document Server

    Aryan, Naser Pour

    2015-01-01

    This book describes the basic principles of designing and modelling inductors, MIM capacitors and coplanar waveguides at frequencies of several tens of GHz. The author explains the design and modelling of key, passive elements, such as capacitors, inductors and transmission lines that enable high frequency MEMS operating at frequencies in the orders of tens of GHz.

  6. Molecular Bremsstrahlung Radiation at GHz Frequencies in Air

    CERN Document Server

    Samarai, I Al; Deligny, O; Letessier-Selvon, A; Montanet, F; Settimo, M; Stassi, P

    2016-01-01

    A detection technique for ultra-high energy cosmic rays, complementary to the fluorescence technique, would be the use of the molecular Bremsstrahlung radiation emitted by low-energy ionization electrons left after the passage of the showers in the atmosphere. In this article, a detailed estimate of the spectral intensity of photons at ground level originating from this radiation is presented. The spectral intensity expected from the passage of the high-energy electrons of the cascade is also estimated. The absorption of the photons in the plasma of electrons/neutral molecules is shown to be negligible. The obtained spectral intensity is shown to be $2\\times10^{-21} $W cm$^{-2}$ GHz$^{-1}$ at 10 km from the shower core for a vertical shower induced by a proton of $10^{17.5}$ eV. In addition, a recent measurement of Bremsstrahlung radiation in air at gigahertz frequencies from a beam of electrons produced at 95 keV by an electron gun is also discussed and reasonably reproduced by the model.

  7. A 260-340 GHz Dual Chip Frequency Tripler for THz Frequency Multiplier Chains

    Science.gov (United States)

    Maestrini, Alain; Tripon-Canseliet, Charlotte; Ward, John S.; Gill, John J.; Mehdi, Imran

    2006-01-01

    We designed and fabricated a fix-tuned balanced frequency tripler working in the 260-340 GHz band to be the first stage of a x3x3x3 multiplier chain to 2.7 THz. The design of a dual-chip version of this multiplier featuring an input splitter / output combiner as part of the input / output matching networks of both chips - with no degradation of the expected bandwidth and efficiency- will be presented.

  8. New space research frequency band proposals in the 20- to 40.5-GHz range

    Science.gov (United States)

    Bishop, D. F.

    1991-01-01

    Future space research communications systems may require spectra above 20 GHz. Frequency bands above 20 GHz are identified that are suitable for space research. The selection of the proper bands depends on consideration of interference with other radio services, adequate bandwidths, link performance, and technical requirements for practical implementation.

  9. Hysteresis effects in instantaneous frequency scaling of attenuation on 20 and 30 GHz satellite links

    Science.gov (United States)

    Sweeney, D. G.; Pratt, T.; Bostian, C. W.

    1992-01-01

    It has been observed with 20/30 GHz satellite beacon measurements that the ratio of 30 GHz to 20 GHz attenuation changes during some fade events. This ratio displays a hysteresis effect. This effect can be explained by a change in the drop size distribution (DSD) during the event. However, it appears only above approximately 6-8 dB of attenuation at 20 GHz. Instantaneous frequency scaling of attenuation is being proposed as part of an algorithm for uplink power control (ULPC) and the dynamic range of such an algorithm must be appropriately limited to avoid the hysteresis.

  10. A 60 GHz Planar Frequency Multiplier Feed on a Silicon Dielectric-Filled Parabola

    Science.gov (United States)

    Kim, M.; Fujiwra, B. H.; Humphrey, D. A.; Martin, S. C.; Smith, R. P.; Siegel, P. H.

    1997-01-01

    A novel all-planar quasi-optical schottky varactor diode frequency doubler has been fabricated and has produced more than 1 mW of output power at 600 GHz with an approximately 2 percent conversion efficiency.

  11. Ultra wideband reflector antenna log-periodic feed with operating frequency range 1–20 GHz.

    Directory of Open Access Journals (Sweden)

    F. F. Dubrovka

    2010-05-01

    Full Text Available Results of modeling and optimization of electric characteristics of ultra wideband reflector antenna log-periodic feed, based on two log-periodic antennas array for operating over frequency range 1 -20 GHz, are presented.

  12. Dual frequency 230/690 GHz interferometry at the Submillimeter Array

    CERN Document Server

    Hunter, T R; Blundell, R; Christensen, R D; Kimberk, R S; Leiker, S P; Marrone, D P; Paine, S N; Papa, D C; Patel, N; Riddle, P; Smith, M J; Sridharan, T K; Tong, C Y E; Young, K H; Zhao, J H; Hunter, Todd R.; Barrett, John W.; Blundell, Raymond; Christensen, Robert D.; Kimberk, Robert S.; Leiker, Steven P.; Marrone, Daniel P.; Paine, Scott N.; Patel, Nimesh; Riddle, Patricia; Smith, Michael J.; Young, Ken H.; Zhao, Jun-Hui

    2005-01-01

    The Submillimeter Array (SMA), a collaboration between the Smithsonian Astrophysical Observatory and the Academica Sinica Institute for Astronomy and Astrophysics of Taiwan, is an eight-element radio-interferometer designed to operate throughout the major atmospheric windows from about 180 to 900 GHz. In an effort to mitigate the effects of atmospheric instabilities which limit the phase coherence of the array especially in the higher frequency bands, the array was designed to allow simultaneous operation of a low frequency receiver (330 GHz). The overlap region of 330-350 GHz was included to facilitate dual polarization measurements in the frequency range considered to offer the highest sensitivity for continuum observations with the array. So far, the array is equipped with working SIS receivers covering the frequency ranges 176-256 GHz, 260-350 GHz, and 600-700 GHz, and single frequency operation has been routine in the lower two frequency bands for the past year. More recently, with the completion of IF h...

  13. 75 FR 9850 - Tank Level Probing Radars in the Frequency Band 77-81 GHz

    Science.gov (United States)

    2010-03-04

    ... frequency band. Radiated emission limits. Siemens requests that the Commission establish a peak EIRP level... obtain comments regarding proposed changes to the regulations for radio frequency devices that do not... COMMISSION 47 CFR Part 15 Tank Level Probing Radars in the Frequency Band 77-81 GHz AGENCY:...

  14. A 20 GHz Bright Sample for Delta > 72 deg - II. Multi-frequency Follow-up

    CERN Document Server

    Ricci, R; Verma, R; Prandoni, I; Carretti, E; Mack, K -H; Massardi, M; Procopio, P; Zanichelli, A; Gregorini, L; Mantovani, F; Gawronski, M P; Peel, M W

    2013-01-01

    We present follow-up observations at 5, 8 and 30 GHz of the K-band Northern Wide Survey (KNoWS) 20 GHz Bright Sample, performed with the 32-m Medicina Radio Telescope and the 32-m Torun Radio Telescope. The KNoWS sources were selected in the Northern Polar Cap (Delta > 72 deg) and have a flux density limit S(20GHz) = 115 mJy. We include NVSS 1.4 GHz measurements to derive the source radio spectra between 1.4 and 30 GHz. Based on optical identifications, 68 per cent of the sources are QSOs, and 27 per cent are radio galaxies. A redshift measurement is available for 58 per cent of the sources. The radio spectral properties of the different source populations are found to be in agreement with those of other high-frequency selected samples.

  15. A review of satellite communication and propagation experiments for frequencies above 10 GHz

    Science.gov (United States)

    Setty, P. N. R.; Goessl, H.; Hounam, D.

    1983-02-01

    Satellite experiments aimed at improving communications in the higher frequency bands, especially above 10 GHz, are described. The basic types of transmission and measurement methods in these experiments are discussed, including beacon transmission, transmission from the ground with measurement on the ground.The satellite experiments considered include: ATS-5 millimeter wave propagation experiments; ATS-6 experiments at 13, 18, 20 and 30 GHz; Comstar experiments at 19 and 28 GHz; experiments with the CTS, ETS-II, SIRIO, CS, BSE, and OTS satellites. The payload parameters of the satellites are shown, and functional block diagrams for the ground terminals are presented.

  16. Frequency notched wide slot antenna for UWB/2.4 GHz WLAN applications

    Institute of Scientific and Technical Information of China (English)

    L(U) Wen-jun; ZHU Hong-bo

    2007-01-01

    A compact frequency notched microstrip slot antenna for ultra-wideband (UWB) /2.4 GHz-band wireless local area network (WLAN) applications is proposed. The antenna is similar to a conventional microstrip slot antenna; however, by introducing a cross wide slot and a meandered-slotted stub, both compact size and frequency notched function can be achieved. It has been studied both numerically and experi- mentally for its impedance bandwidth, surface current distribution, radiation patterns, and gain. As will be seen, an operation bandwidth of over 4.6:1 ranging from 2.39 to 11.25 GHz for return loss lower than having a frequency notched band ranging from 4.75 to 5.85 GHz has been achieved, and good radiation performance over the entire frequency range has also been achieved.

  17. Design, Prototyping and Measurement of a Cascaded 6-GHz Frequency Selective Surface Array

    Directory of Open Access Journals (Sweden)

    Marcelo Bender Perotoni

    2016-04-01

    Full Text Available The design, prototyping, and free-space measurement of a 6-GHz Frequency Selective Surface filter is presented. The prototyping resolution of a large (A4 sheet size Frequency Selective Surface with small loops as elements is checked, as well as the correlation with measurements performed with a 3-D full-wave solver. The test also involved the effect of cascading two different Frequency Selective Surfaces with a viewpoint towards a narrower frequency range, which provided good results.

  18. The widest-frequency radio relic spectra: observations from 150 MHz to 30 GHz

    CERN Document Server

    Stroe, Andra; Rumsey, Clare; van Weeren, Reinout; Kierdorf, Maja; Donnert, Julius; Jones, Thomas W; Röttgering, Huub J A; Hoeft, Matthias; Rodriguez-Gonzalvez, Carmen; Harwood, Jeremy J; Saunders, Richard D E

    2015-01-01

    Radio relics are patches of diffuse synchrotron radio emission that trace shock waves. Relics are thought to form when intra-cluster medium electrons are accelerated by cluster merger induced shock waves through the diffusive shock acceleration mechanism. In this paper, we present observations spanning 150 MHz to 30 GHz of the `Sausage' and `Toothbrush' relics from the Giant Metrewave and Westerbork telescopes, the Karl G. Jansky Very Large Array, the Effelsberg telescope, the Arcminute Microkelvin Imager and Combined Array for Research in Millimeter-wave Astronomy. We detect both relics at 30 GHz, where the previous highest frequency detection was at 16 GHz. The integrated radio spectra of both sources clearly steepen above 2 GHz, at the >6$\\sigma$ significance level, supports the spectral steepening previously found in the `Sausage' and the Abell 2256 relic. Our results challenge the widely adopted simple formation mechanism of radio relics and suggest more complicated models have to be developed that, for ...

  19. A fast vectorial network analyser for frequencies up to 4 GHz

    Directory of Open Access Journals (Sweden)

    B. Schulte

    2004-01-01

    Full Text Available A fast four channel network analyser is introduced to measure S-parameters in a frequency range from 10MHz to 4GHz. The measurement period of this kind of network analyser is short in comparison with a conventional one, which becomes possible by using highly linear analogue frequency ramps, realized with fractional divider phase locked loop circuits. The settling time for the discrete frequency points, which is typical for a conventional network analyser, is nearly eliminated by the use of frequency ramps. To achieve the necessary bandwidth of 4 GHz in the baseband, a heterodyne principle is applied. A VCO-signal from 5 to 9 GHz is down converted to the baseband with a fixed frequency generator of 9 GHz. The structure of the following network analyser is similar to the structure of a conventional four channel network analyser and therefore all known calibration techniques are suited for the fast network analyser. The intermediate frequency, which is necessary for the evaluation, carries the required information. However a special analysis technique is necessary. This technique is based on two Fourier transformations.

  20. Human exposure to pulsed fields in the frequency range from 6 to 100 GHz

    Science.gov (United States)

    Laakso, Ilkka; Morimoto, Ryota; Heinonen, Juhani; Jokela, Kari; Hirata, Akimasa

    2017-09-01

    Restrictions on human exposure to electromagnetic waves at frequencies higher than 3-10 GHz are defined in terms of the incident power density to prevent excessive temperature rise in superficial tissue. However, international standards and guidelines differ in their definitions of how the power density is interpreted for brief exposures. This study investigated how the temperature rise was affected by exposure duration at frequencies higher than 6 GHz. Far-field exposure of the human face to pulses shorter than 10 s at frequencies from 6 to 100 GHz was modelled using the finite-difference time-domain method. The bioheat transfer equation was used for thermal modelling. We investigated the effects of frequency, polarization, exposure duration, and depth below the skin surface on the temperature rise. The results indicated limitations in the current human exposure guidelines and showed that radiant exposure, i.e. energy absorption per unit area, can be used to limit temperature rise for pulsed exposure. The data are useful for the development of human exposure guidelines at frequencies higher than 6 GHz.

  1. Design of Miniature Patch Antenna Around the Frequency 3.5 GHz for WIMAX Technology

    Directory of Open Access Journals (Sweden)

    Adnane Latif

    2012-01-01

    Full Text Available This work aims to study a miniature rectangular patch antenna and#955; / 8 fed by coaxial probe with the transmission line method (TLM. The design and simulation of this antenna is around the frequency of 3.5GHz, for WIMAX technology. The results obtained (input impedance, reflection coefficient, VSWR and bandwidth are given by the program in the software MATLAB.

  2. Ferrite Film Loaded Frequency Selective Metamaterials for Sub-GHz Applications.

    Science.gov (United States)

    Gao, Bo; Yuen, Matthew M F; Ye, Terry

    2016-12-13

    Electromagnetic metamaterials are constructed with sub-wavelength structures that exhibit particular electromagnetic properties under a certain frequency range. Because the form-factor of the substructures has to be comparable to the wavelength of the operating frequency, few papers have discussed the metamaterials under GHz frequency. In this paper, we developed an innovative method to reduce the resonant frequency of metamaterals. By integrating the meta-structures with ferrite materials of higher permeability, the cell size of the meta-structure can be scaled down. This paper describes the methodology, design, and development of low-profile GHz ferrite loaded metamaterials. A ferrite film with a permeability of 20 could reduce the resonant frequency of metamaterials by up to 50%. A prototype has been fabricated and the measurement data align well with the simulation results. Because of the lowered operational frequency, the proposed ferrite loaded metamaterials offer more flexibility for various sub-GHz microwave applications, such as cloaks, absorbers, and frequency selective surfaces.

  3. Ferrite Film Loaded Frequency Selective Metamaterials for Sub-GHz Applications

    Directory of Open Access Journals (Sweden)

    Bo Gao

    2016-12-01

    Full Text Available Electromagnetic metamaterials are constructed with sub-wavelength structures that exhibit particular electromagnetic properties under a certain frequency range. Because the form-factor of the substructures has to be comparable to the wavelength of the operating frequency, few papers have discussed the metamaterials under GHz frequency. In this paper, we developed an innovative method to reduce the resonant frequency of metamaterals. By integrating the meta-structures with ferrite materials of higher permeability, the cell size of the meta-structure can be scaled down. This paper describes the methodology, design, and development of low-profile GHz ferrite loaded metamaterials. A ferrite film with a permeability of 20 could reduce the resonant frequency of metamaterials by up to 50%. A prototype has been fabricated and the measurement data align well with the simulation results. Because of the lowered operational frequency, the proposed ferrite loaded metamaterials offer more flexibility for various sub-GHz microwave applications, such as cloaks, absorbers, and frequency selective surfaces.

  4. A new resonant circuit for 2.45 GHz LC VCO with linear frequency tuning

    OpenAIRE

    Zihir, Samet; Taşdemir, Ferhat; Tasdemir, Ferhat; Dinç, Tolga; Dinc, Tolga; Gürbüz, Yaşar; Gurbuz, Yasar

    2011-01-01

    A new MOS varactor bank is proposed to implement a 2.45 GHz SiGe BiCMOS LC-tank voltage controlled oscillator (VCO) with linear frequency tuning. Compared to a conventional VCO, the proposed technique improves the quality factor of the LC-tank while preserving the linearity of the circuit. Realized in 0.25-μm SiGe BiCMOS technology, VCO exhibits 35% VCO gain (KVCO) variation from 2.29 to 2.66 GHz with a 16% tuning ratio. The VCO also exhibits a phase noise of -113 dBc/Hz at 1 MHz offset fr...

  5. Sustaining GHz oscillation of carbon nanotube based oscillators via a MHz frequency excitation

    Science.gov (United States)

    Motevalli, Benyamin; Taherifar, Neda; Zhe Liu, Jefferson

    2016-05-01

    There have been intensive studies to investigate the properties of gigahertz nano-oscillators based on multi-walled carbon nanotubes (MWCNTs). Many of these studies, however, revealed that the unique telescopic translational oscillations in such devices would damp quickly due to various energy dissipation mechanisms. This challenge remains the primary obstacle against its practical applications. Herein, we propose a design concept in which a GHz oscillation could be re-excited by a MHz mechanical motion. This design involves a triple-walled CNT, in which sliding of the longer inner tube at a MHz frequency can re-excite and sustain a GHz oscillation of the shorter middle tube. Our molecular dynamics (MD) simulations prove this design concept at ˜10 nm scale. A mathematical model is developed to explore the feasibility at a larger size scale. As an example, in an oscillatory system with the CNT’s length above 100 nm, the high oscillatory frequency range of 1.8-3.3 GHz could be excited by moving the inner tube at a much lower frequency of 53.4 MHz. This design concept together with the mechanical model could energize the development of GHz nano-oscillators in miniaturized electro-mechanical devices.

  6. On the Zebra Structure in the Frequency Range near 3 GHz

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We present 19 cases of zebra pattern structure (ZPS) and fiber bursts(FB) in radio bursts in frequency range around 3 GHz, and one such case in the range 5.2-7.6 GHz, using the new microwave spectrometer of NAOC between 2.6-3.8 and 5.2-7.6 GHz (China, Huairou station) with high resolution (10 MHz and 8 ms). The FB and ZPS have about the same spectral parameters: the frequency bandwidth of emission stripes △f ~ 20 MHz, the frequency separation between the emission and the neighboring low frequency absorption -△fea ~ 30 MHz and the frequency separation between emission stripes (when a periodic structure persists)△fs ~ 60-70 MHz. Therefore we consider both these fine structures to be whistlermanifestations, i.e., interactions of plasma electrostatic waves with whistler waves(generated by the same fast particles with loss-cone anisotropy) l + w → t. The duration of the fiber bursts of about 2 s corresponds to whistler waves propagat-ing undamped at about 2s, which requires a whistler increment < 0.5 s-1. Inthe frequency range 3-7 GHz the relation between the ratios of plasma to cyclotronfrequencies and whistler to cyclotron frequencies is almost independent of the decre-ment of whistler electron damping. This finding is used to obtain the magnetic fieldstrength in the region of generation. For a reasonable value of electron temperature(2-20 MK), we find B = 125-190 G when the electron density is (8-18) x 1010 cm-3and B = 520 - 610 G when the electron density is (35-60) × 1010 cm-3. In two re-markable events, 1998-04-15 and 2000-10-29, the right-hand polarization is strong for all the fine structures and corresponds to ordinary wave.

  7. In-Phase Power-Combined Frequency Tripler at 300 GHz

    Science.gov (United States)

    Maestrini, Alain; Ward, John; Lin, Robert; Gill, John; Lee, Choonsup; Mehdi, Imran; Javadi, Hamid; Chattopadhyay, Goutam

    2009-01-01

    This design starts with commercial 85- to 115-GHz sources that are amplified to as much as 250 mW using power amplifiers developed for the Herschel Space Observatory. The frequency is then tripled using a novel waveguide GaAs Schottky diode frequency tripler. This planar diode produces 26 mW at 318 GHz. Peak conversion efficiency is over 15 percent, and the measured bandwidth of about 265 - 30 GHz is limited more by the driving source than by the tripler itself. This innovation is based on an integrated circuit designed originally for a single-chip 260- to 340-GHz balanced tripler. The power-combined version has two mirror-image tripler chips that are power-combined in-phase in a single waveguide block using a compact Y-junction divider at the input waveguide, and a Y-junction combiner at the output waveguide. The tripler uses a split-block waveguide design with two independent DC bias lines.

  8. A low-phase-noise 18 GHz Kerr frequency microcomb phase-locked over 65 THz

    CERN Document Server

    Huang, S -W; Zhou, H; Yu, M; Kwong, D -L; Wong, C W

    2015-01-01

    Laser frequency combs are coherent light sources that simultaneously provide pristine frequency spacings for precision metrology and the fundamental basis for ultrafast and attosecond sciences. Recently, nonlinear parametric conversion in high-Q microresonators has been suggested as an alternative platform for optical frequency combs, though almost all in 100 GHz frequencies or more. Here we report a low-phase-noise on-chip Kerr frequency comb with mode spacing compatible with high-speed silicon optoelectronics. The waveguide cross-section of the silicon nitride spiral resonator is designed to possess small and flattened group velocity dispersion, so that the Kerr frequency comb contains a record-high number of 3,600 phase-locked comb lines. We study the single-sideband phase noise as well as the long-term frequency stability and report the lowest phase noise floor achieved to date with -130 dBc/Hz at 1 MHz offset for the 18 GHz Kerr comb oscillator, along with feedback stabilization to achieve frequency Alla...

  9. The functional correlation between rainfall rate and extinction coefficient for frequencies from 3 to 10 GHz

    Science.gov (United States)

    Jameson, A. R.

    1990-01-01

    The relationship between the rainfall rate (R) obtained from radiometric brightness temperatures and the extinction coefficient (k sub e) is investigated by computing the values of k sub e over a wide range of rainfall rates, for frequencies from 3 to 25 GHz. The results show that the strength of the relation between the R and the k sub e values exhibits considerable variation for frequencies at this range. Practical suggestions are made concerning the selection of particular frequencies for rain measurements to minimize the error in R determinations.

  10. Cavity design and linear analysis of 225 GHz frequency-quadrupling gyroklystron

    Institute of Scientific and Technical Information of China (English)

    Liu Di-Wei; Yuan Xue-Song; Yan Yang; Liu Sheng-Gang

    2009-01-01

    This paper considers the frequency-quadrupling three-cavity gyroklystrons with successive frequency-doubling in each cavity. The cavities of 225 GHz frequency-quadrupling gyroklystron are designed with the scattering matrices method and the possible operating mode are discussed. With the point-gap theory, the starting currents of the possible operating modes and the potential parasitic modes in the output cavity are calculated. The optimal operating mode is proposed under consideration of the mode competition and the power capacity of the cavity.

  11. Design of a Wideband 900 GHz Balanced Frequency Tripler for Radioastronomy

    Science.gov (United States)

    Tripon-Canseliet, Charlotte; Maestrini, Alain; Mehdi, Imran

    2004-01-01

    We report on the design of a fix-tuned split-block waveguide balanced frequency tripler working nominally at 900GHz. It uses a GaAs Schottky planar diode pair in a balanced configuration. The circuit will be fabricated with JPL membrane technology in order to minimize dielectric loading. The multiplier is bias-less to dramatically ease the mounting and the operating procedure. At room temperature, the expected output power is 50- 130 (micro)W in the band 800-970 GHz when the tripler is pumped with 4mW. By modifying the waveguide input and output matching circuit, the multiplier can be tuned to operate at lower frequencies.

  12. Higher-order modulations of fs laser pulses for GHz frequency domain photon migration system.

    Science.gov (United States)

    Lin, Huang-Yi; Cheng, Nanyu; Tseng, Sheng-Hao; Chan, Ming-Che

    2014-02-24

    Except the fundamental modulation frequency, by higher-order-harmonic modulations of mode-locked laser pulses and a simple frequency demodulation circuit, a novel approach to GHz frequency-domain-photon-migration (FDPM) system was reported. With this novel approach, a wide-band modulation frequency comb is available without any external modulation devices and the only electronics to extract the optical attenuation and phase properties at a selected modulation frequency in FDPM systems are good mixers and lock-in devices. This approach greatly expands the frequency range that could be achieved by conventional FDPM systems and suggests that our system could extract much more information from biological tissues than the conventional FDPM systems. Moreover, this demonstration will be beneficial for discerning the minute change of tissue properties.

  13. Thermal Injury in Human Subjects Due to 94-GHz Radio Frequency Radiation Exposures

    Science.gov (United States)

    2016-02-24

    AFRL-RH-FS-TR-2016-0001 Thermal Injury in Human Subjects Due to 94-GHz Radio Frequency Radiation Exposures James E. Parker General...them. This report was cleared for public release by the 88th ABW Public Affairs Office and is available to the general public, including foreign ...This report is published in the interest of scientific and technical information exchange , and its

  14. Robust Pressure-Actuated Liquid Metal Devices Showing Reconfigurable Electromagnetic Effects at GHz Frequencies (POSTPRINT)

    Science.gov (United States)

    2014-06-01

    actuated liquid metal devices are demonstrated for reconfigurable electromagnetic fundamentals at GHz frequencies, including tunable dipole antennas ...Mazlouman, A. Mahanfar, C. Menon et al., “Mechanically Reconfigurable Antennas using Electro-active Polymers (EAPs),” 2011 Ieee International Symposium...on Antennas and Propagation (Apsursi), pp. 742-745, 2011. [3] B. Cumby, G. Hayes, M. Dickey et al., “ Reconfigurable liquid metal circuits by

  15. High-Frequency Wireless Communications System: 2.45-GHz Front-End Circuit and System Integration

    Science.gov (United States)

    Chen, M.-H.; Huang, M.-C.; Ting, Y.-C.; Chen, H.-H.; Li, T.-L.

    2010-01-01

    In this article, a course on high-frequency wireless communications systems is presented. With the 145-MHz baseband subsystem available from a prerequisite course, the present course emphasizes the design and implementation of the 2.45-GHz front-end subsystem as well as system integration issues. In this curriculum, the 2.45-GHz front-end…

  16. High-Frequency Wireless Communications System: 2.45-GHz Front-End Circuit and System Integration

    Science.gov (United States)

    Chen, M.-H.; Huang, M.-C.; Ting, Y.-C.; Chen, H.-H.; Li, T.-L.

    2010-01-01

    In this article, a course on high-frequency wireless communications systems is presented. With the 145-MHz baseband subsystem available from a prerequisite course, the present course emphasizes the design and implementation of the 2.45-GHz front-end subsystem as well as system integration issues. In this curriculum, the 2.45-GHz front-end…

  17. Dual-Comb Coherent Raman Spectroscopy with Lasers of 1-GHz Pulse Repetition Frequency

    CERN Document Server

    Mohler, Kathrin J; Yan, Ming; Hänsch, Theodor W; Picqué, Nathalie

    2016-01-01

    We extend the technique of multiplex coherent Raman spectroscopy with two femtosecond mode-locked lasers to oscillators of a pulse repetition frequency of 1 GHz. We demonstrate spectra of liquids, which span 1100 cm$^{-1}$ of Raman shifts. At a resolution of 6 cm$^{-1}$, their measurement time may be as short as 5 microseconds for a refresh rate of 2 kHz. The waiting period between acquisitions is improved ten-fold compared to previous experiments with two lasers of 100-MHz repetition frequencies.

  18. System-on-Package MHMIC Milimeter-Wave Frequency Synthesizer for 60 GHz WPANs

    Directory of Open Access Journals (Sweden)

    Boris Spokoinyi

    2012-01-01

    Full Text Available We present a low-cost millimeter-wave frequency synthesizer with ultralow phase noise, implemented using system-on-package (SoP techniques for high-data-rate wireless personal area network (WPAN systems operating in the unlicensed 60 GHz ISM band (57–64 GHz. The phase noise specification of the proposed frequency synthesizer is derived for a worst case scenario of an 802.11.3c system, which uses a 64-QAM 512-carrier-OFDM modulation, and a data rate of 5.775 Gbps. Our design approach adopts commercial-of-the-shelf (COTS components integrated in a low-cost alumina-based miniature hybrid microwave integrated circuit (MHMIC package. The proposed design approach reduces not only the system cost and time-to-market, but also enhances the system performance in comparison with system-on-chip (SoC designs. The synthesizer has measured phase noise of -111.5 dBc/Hz at 1 MHz offset and integrated phase noise of 2.8° (simulated: 2.5° measured at 57.6 GHz with output power of +1 dBm.

  19. Mechanically robust 39 GHz cut-off frequency graphene field effect transistors on flexible substrates.

    Science.gov (United States)

    Wei, Wei; Pallecchi, Emiliano; Haque, Samiul; Borini, Stefano; Avramovic, Vanessa; Centeno, Alba; Amaia, Zurutuza; Happy, Henri

    2016-08-07

    Graphene has been regarded as a promising candidate channel material for flexible devices operating at radio-frequency (RF). In this work we fabricated and fully characterized double bottom-gate graphene field effect transistors on flexible polymer substrates for high frequency applications. We report a record high as-measured current gain cut-off frequency (ft) of 39 GHz. The corresponding maximum oscillation frequency (fmax) is 13.5 GHz. These state of the art high frequency performances are stable against bending, with a typical variation of around 10%, for a bending radius of up to 12 mm. To demonstrate the reliability of our devices, we performed a fatigue stress test for RF-GFETs which were dynamically bend tested 1000 times at 1 Hz. The devices are mechanically robust, and performances are stable with typical variations of 15%. Finally we investigate thermal dissipation, which is a critical parameter for flexible electronics. We show that at the optimum polarization the normalized power dissipated by the GFETs is about 0.35 mW μm(-2) and that the substrate temperature is around 200 degree centigrade. At a higher power, irreversible degradations of the performances are observed. Our study on state of the art flexible GFETs demonstrates mechanical robustness and stability upon heating, two important elements to assess the potential of GFETs for flexible electronics.

  20. High-resolution ADC operation up to 19.6 GHz clock frequency

    Science.gov (United States)

    Mukhanov, O. A.; Semenov, V. K.; Vernik, I. V.; Kadin, A. M.; Filippov, T. V.; Gupta, D.; Brock, D. K.; Rochwarger, I.; Polyakov, Y. A.

    2001-12-01

    We have designed, fabricated and tested the second-generation (2G) design of a high-resolution, dynamically programmable analog-to-digital converter (ADC) for radar and communications applications. The ADC chip uses the phase modulation-demodulation architecture and on-chip digital filtering. The 2G ADC design has been substantially enhanced. Both ADC front-end modulator and demodulator, as well as decimation digital filter, have been redesigned for operation at 20 GHz. Test results of this 6000 Josephson junction 2G ADC chip at clock frequencies up to 19.6 GHz are described. These test results were compared to the results of ADC functional simulation using MATLAB.

  1. Frequency and Temperature Dependence of Electrical Breakdown at 21, 30 and 39 GHz

    CERN Document Server

    Braun, Hans Heinrich; Wilson, Ian H; Wuensch, Walter

    2003-01-01

    A TeV-range e+e- linear collider has emerged as one of the most promising candidates to extend the high energy frontier of experimental elementary particle physics. A high accelerating gradient for such a collider is desirable to limit its overall length. Accelerating gradient is mainly limited by electrical breakdown, and it has been generally assumed that this limit increases with increasing frequency for normal-conducting accelerating structures. Since the choice of frequency has a profound influence on the design of a linear collider, the frequency dependence of breakdown has been measured using six exactly scaled single-cell cavities at 21, 30, and 39 GHz. The influence of temperature on breakdown behavior was also investigated. The maximum obtainable surface fields were found to be in the range of 300 to 400 MV/m for copper, with no significant dependence on either frequency or temperature.

  2. An Empirical Outdoor-to-Indoor Path Loss Model from below 6 GHz to cm-Wave Frequency Bands

    DEFF Research Database (Denmark)

    Rodriguez Larrad, Ignacio; Nguyen, Huan Cong; Kovács, István Z.;

    2016-01-01

    This letter presents an empirical multi-frequency outdoor-to-indoor path loss model. The model is based on measurements performed on the exact same set of scenarios for different frequency bands ranging from traditional cellular allocations below 6 GHz (0.8, 2, 3.5 and 5.2 GHz), up to cm-wave fre......This letter presents an empirical multi-frequency outdoor-to-indoor path loss model. The model is based on measurements performed on the exact same set of scenarios for different frequency bands ranging from traditional cellular allocations below 6 GHz (0.8, 2, 3.5 and 5.2 GHz), up to cm...

  3. Active mode locking at 50 GHz repetition frequency by half-frequency modulation of monolithic semiconductor lasers integrated with electroabsorption modulators

    Science.gov (United States)

    Sato, Kenji; Kotaka, Isamu; Kondo, Yasuhiro; Yamamoto, Mitsuo

    1996-10-01

    Active mode locking achieved at a 50 GHz repetition frequency by modulation at half (25 GHz) the cavity resonance frequency using a monolithic mode-locked InGaAsP laser integrated with an electroabsorption modulator is described. A pulse width of around 3 ps and a high suppression ratio of more than 33 dB of the intensity modulation at the driving frequency are obtained.

  4. An InGaAs/InP 40 GHz CML static frequency divider

    Institute of Scientific and Technical Information of China (English)

    Su Yongbo; Jin Zhi; Cheng Wei; Ge Ji; Wang Xiantai; Chen Gaopeng; Liu Xinyu; Xu Anhuai; Qi Ming

    2011-01-01

    Static frequency dividers are widely used as a circuit performance benchmark or figure-of-merit indicator to gauge a particular device technology's ability to implement high speed digital and integrated high performance mixed-signal circuits.We report a 2:1 static frequency divider in InGaAs/InP heterojunction bipolar transistor technology.This is the first InP based digital integrated circuit ever reported on the mainland of China.The divider is implemented in differential current mode logic (CML) with 30 transistors.The circuit operated at a peak clock frequency of 40 GHz and dissipated 650 mW from a single -5 V supply.

  5. a New Broadband Cavity Enhanced Frequency Comb Spectroscopy Technique Using GHz Vernier Filtering.

    Science.gov (United States)

    Morville, Jérôme; Rutkowski, Lucile; Dobrev, Georgi; Crozet, Patrick

    2015-06-01

    We present a new approach to Cavity Enhanced - Direct Frequency Comb Spectroscopy where the full emission bandwidth of a Titanium:Sapphire laser is exploited at GHz resolution. The technique is based on a low-resolution Vernier filtering obtained with an appreciable -actively stabilized- mismatch between the cavity Free Spectral Range and the laser repetition rate, using a diffraction grating and a split-photodiode. This particular approach provides an immunity to frequency-amplitude noise conversion, reaching an absorption baseline noise in the 10-9 cm-1 range with a cavity finesse of only 3000. Spectra covering 1800 cm-1 (˜ 55 THz) are acquired in recording times of about 1 second, providing an absorption figure of merit of a few 10-11 cm-1/√{Hz}. Initially tested with ambient air, we report progress in using the Vernier frequency comb method with a discharge source of small radicals. Rutkowski et al, Opt. Lett., 39(23)2014

  6. Electromagnetic interference shielding effectiveness of composite carbon nanotube macro-film at a high frequency range of 40 GHz to 60 GHz

    Directory of Open Access Journals (Sweden)

    Zi Ping Wu

    2015-06-01

    Full Text Available The electromagnetic interference (EMI shielding effectiveness (SE of carbon nanotube (CNT macro-film that is adhered to common cloth to maintain the light weight, silk-like quality, and smooth surface of the material for EMI shielding is investigated. The results show that a high and stable EMI SE of 48 dB to 57 dB at 40 GHz to 60 GHz was obtained by the macro-film with a thickness of only ∼4 μm. The composite CNT macro-film is easily manipulated, and its EMI property is significantly different from that of traditional electromagnetic shielding materials that show a lower EMI SE with increasing frequency. For example, the EMI SE of Cu foils decrease from 75 dB to 35 dB as frequency increases from 25 GHz to 60 GHz. Considering their stable and outstanding EMI SE and easy manipulation, the composite CNT macro-films are expected to have potential applications in shielding against millimeter waves.

  7. Radio Frequency Surface Impedance Characterization System for Superconducting Samples at 7.5 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Binping Xiao, Charles Reece, Michael Kelley, Larry Phillips, Rongli Geng, Haipeng Wang, Frank Marhauser

    2011-05-01

    A radio frequency (RF) surface impedance characterization (SIC) system that uses a sapphire-loaded Nb cavity operating at 7.5 GHz has been fabricated to measure the RF surface impedance of flat superconducting samples. Currently, the SIC system can make direct calorimetric surface impedance measurements in the central 0.8 cm2 area of 5 cm diameter disk samples in a temperature range from 2 to 20 K, exposed to a magnetic flux density of up to 14 mT. As an application, we present the measurement results for a bulk Nb sample.

  8. Design and Characterization of a 5.2 GHz/2.4 GHz Fractional- Frequency Synthesizer for Low-Phase Noise Performance

    Directory of Open Access Journals (Sweden)

    Dai Foster F

    2006-01-01

    Full Text Available This paper presents a complete noise analysis of a -based fractional- phase-locked loop (PLL based frequency synthesizer. Rigorous analytical and empirical formulas have been given to model various phase noise sources and spurious components and to predict their impact on the overall synthesizer noise performance. These formulas have been applied to an integrated multiband WLAN frequency synthesizer RFIC to demonstrate noise minimization through judicious choice of loop parameters. Finally, predicted and measured phase jitter showed good agreement. For an LO frequency of 4.3 GHz, predicted and measured phase noise was rms and rms, respectively.

  9. Design and Characterization of a 5.2 GHz/2.4 GHz ΣΔ Fractional- N Frequency Synthesizer for Low-Phase Noise Performance

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available This paper presents a complete noise analysis of a ΣΔ -based fractional- N phase-locked loop (PLL based frequency synthesizer. Rigorous analytical and empirical formulas have been given to model various phase noise sources and spurious components and to predict their impact on the overall synthesizer noise performance. These formulas have been applied to an integrated multiband WLAN frequency synthesizer RFIC to demonstrate noise minimization through judicious choice of loop parameters. Finally, predicted and measured phase jitter showed good agreement. For an LO frequency of 4.3 GHz, predicted and measured phase noise was 0.50 ° rms and 0.535 ° rms, respectively.

  10. Nanostructured composite layers for electromagnetic shielding in the GHz frequency range

    Energy Technology Data Exchange (ETDEWEB)

    Suchea, M. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Chemistry and Physics, “Al.I. Cuza” University of Iasi, Iasi (Romania); Tudose, I.V. [Chemistry and Physics, “Al.I. Cuza” University of Iasi, Iasi (Romania); Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Tzagkarakis, G. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Kenanakis, G. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas, Heraklion (Greece); Katharakis, M. [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Drakakis, E. [Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Koudoumas, E., E-mail: koudoumas@staff.teicrete.gr [Center of Materials Technology and Photonics, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece); Electrical Engineering Department, School of Engineering, Technological Educational Institute of Crete, Heraklion (Greece)

    2015-10-15

    Graphical abstract: - Highlights: • Paint-like nanocomposite layers consisting of graphene nanoplatelets, PANI:HCl and PEDOT:PSS present very effective attenuation of electromagnetic radiation in the frequency range 4–20 GHz. • The shielding performance is based mostly on the graphene nanoplatelets and supported by PANI:HCl. In contrast, PEDOT:PSS plays mainly the role of the binder. • Increasing resistivity was observed to reduce the shielding effect, while increasing thickness to favor it. - Abstract: We report on preliminary results regarding the applicability of nanostructured composite layers for electromagnetic shielding in the frequency range of 4–20 GHz. Various combinations of materials were employed including poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS), polyaniline, graphene nanoplatelets, carbon nanotubes, Cu nanoparticles and Poly(vinyl alcohol). As shown, paint-like nanocomposite layers consisting of graphene nanoplatelets, polyaniline PEDOT:PSS and Poly(vinyl alcohol) can offer quite effective electromagnetic shielding, similar or even better than that of commercial products, the response strongly depending on their thickness and resistivity.

  11. High-frequency electromagnetic properties of soft magnetic Nd2Co17 micron flakes fractured along c crystal plane with natural resonance frequency exceeding 10 GHz

    Science.gov (United States)

    Zhang, Yongbo; Wang, Peng; Ma, Tianyong; Wang, Ying; Qiao, Liang; Wang, Tao

    2016-02-01

    Planar anisotropy Nd2Co17 flakes fractured along c crystal plane were fabricated by surfactant-assisted high-energy ball milling technique. The magnetic flakes have a diameter range of 5-20 μm and a typical thickness of approximately 120 nm. The frequency dependence of complex permeability of Nd2Co17 epoxy resin composite has been investigated in the frequency range of 0.1-18 GHz. The measurement results show that the natural resonance frequency reaches 12.5 GHz while the initial permeability survives up to 2.26. The superior high frequency properties come from the large out-of-plane anisotropy field and the flake structure fractured along the c crystal plane of Nd2Co17. The planar anisotropic Nd2Co17 flakes have significant potential applications in the high-frequency devices working in the frequency beyond 10 GHz.

  12. Low Power Phase Locked Loop Frequency Synthesizer for 2.4 GHz Band Zigbee

    Directory of Open Access Journals (Sweden)

    Nesreen M.H. Ismail

    2009-01-01

    Full Text Available Problem statement: Wireless communication systems are required for many applications. There are different standards for these systems. IEEE 802.15.4 defines the communication system standard for zigbee. This study discussed designing one of the blocks of zigbee transceiver which is the Phase Locked Loop (PLL. A major target for any communication systems is saving battery power, especially for zigbee as it is meant to be a low cost communication system. Phase Locked Loop is responsible on carrier frequency selection in a communication system. It is the most power consumer block in the transceiver as well. The objective of this study was designing a low power fully integrated integer-N PLL frequency synthesizer targeting the 2.4 GHz band IEEE 802.15.4 Std zigbee. Approach: Minimizing total power consumption of PLL was achieved by introducing a novel design of Phase Frequency Detector (PFD and modifying the rest of the PLL blocks. The proposed PFD uses only 12 transistors and it preserved the main characteristics of the conventional PFD with a simple architecture. The Charge Pump (CP was single-ended source switch to save power and minimize mismatches. The Voltage Controlled Oscillator (VCO spans from 4.737-4.977 GHz band using LC resonator. The VCO worked at double the frequency band to avoid local oscillator leakage and feed through. The integer N divider used a 15/16 dual modulus. Results: The proposed PLL was designed using Silterra 0.18 um CMOS process. It consumed 3.2 mW with 1.8 voltage supply. Phase noise is-113.4 dBc Hz-1 at 1 MHz. The proposed PFD works up to 2.5 GHz with free dead zone. The Charge Pump (CP works with 20 uA. lock-in time is 25 us and total die area is 1×2 mm. All results were taken from extracted layout simulations. Conclusion: The results of this study indicated that a PLL can work with less power consumption and save the transceiver battery. The proposed PFD was suitable for high speed applications.

  13. A Monolithic 0.18μm 4GHz CMOS Frequency Synthesizer

    Directory of Open Access Journals (Sweden)

    Li Qing

    2013-02-01

    Full Text Available A 4 GHz PLL (phase-locked loop-type frequency synthesizer has been implemented in the standard 0.18μm mixed-signal and RF 1P6M CMOS technology. It integrates a VCO, a dual-modulus prescaler, PFD, a charge pump, a control logic, various digital counters and digital registers onto a single chip. With the help of the linear model of the loop, the design and optimization of the loop parameters are discussed in detailed. The measured results show that the locked range was 4096-4288 MHz and the phase noise could reach -117 dBc/Hz at 1MHz offset from the carrier 4.154 GHz, the output power is about -3 dBm. The chip area is 0.675 mm×0.700 mm. The DC power consumption of the core part is about 24 mW under 1.8 V supply.

  14. Viscoelastic properties and efficient acoustic damping in confined polymer nano-layers at GHz frequencies

    Science.gov (United States)

    Hettich, Mike; Jacob, Karl; Ristow, Oliver; Schubert, Martin; Bruchhausen, Axel; Gusev, Vitalyi; Dekorsy, Thomas

    2016-01-01

    We investigate the viscoelastic properties of confined molecular nano-layers by time resolved optical pump-probe measurements. Access to the elastic properties is provided by the damping time of acoustic eigenmodes of thin metal films deposited on the molecular nano-layers which show a strong dependence on the molecular layer thickness and on the acoustic eigen-mode frequencies. An analytical model including the viscoelastic properties of the molecular layer allows us to obtain the longitudinal sound velocity as well as the acoustic absorption coefficient of the layer. Our experiments and theoretical analysis indicate for the first time that the molecular nano-layers are much more viscous than elastic in the investigated frequency range from 50 to 120 GHz and thus show pronounced acoustic absorption. The longitudinal acoustic wavenumber has nearly equal real and imaginary parts, both increasing proportional to the square root of the frequency. Thus, both acoustic velocity and acoustic absorption are proportional to the square root of frequency and the propagation of compressional/dilatational acoustic waves in the investigated nano-layers is of the diffusional type, similar to the propagation of shear waves in viscous liquids and thermal waves in solids. PMID:27633351

  15. Viscoelastic properties and efficient acoustic damping in confined polymer nano-layers at GHz frequencies

    Science.gov (United States)

    Hettich, Mike; Jacob, Karl; Ristow, Oliver; Schubert, Martin; Bruchhausen, Axel; Gusev, Vitalyi; Dekorsy, Thomas

    2016-09-01

    We investigate the viscoelastic properties of confined molecular nano-layers by time resolved optical pump-probe measurements. Access to the elastic properties is provided by the damping time of acoustic eigenmodes of thin metal films deposited on the molecular nano-layers which show a strong dependence on the molecular layer thickness and on the acoustic eigen-mode frequencies. An analytical model including the viscoelastic properties of the molecular layer allows us to obtain the longitudinal sound velocity as well as the acoustic absorption coefficient of the layer. Our experiments and theoretical analysis indicate for the first time that the molecular nano-layers are much more viscous than elastic in the investigated frequency range from 50 to 120 GHz and thus show pronounced acoustic absorption. The longitudinal acoustic wavenumber has nearly equal real and imaginary parts, both increasing proportional to the square root of the frequency. Thus, both acoustic velocity and acoustic absorption are proportional to the square root of frequency and the propagation of compressional/dilatational acoustic waves in the investigated nano-layers is of the diffusional type, similar to the propagation of shear waves in viscous liquids and thermal waves in solids.

  16. A High Efficiency Multiple-Anode 260-340 GHz Frequency Tripler

    Science.gov (United States)

    Maestrini, Alain; Tripon-Canseliet, Charlotte; Ward, John S.; Gill, John J.; Mehdi, Imran

    2006-01-01

    We report on the fabrication at the Jet Propulsion Laboratory of a fixed-tuned split-block waveguide balanced frequency tripler working in the 260-340 GHz band. This tripler will be the first stage of a x3x3x3 multiplier chain to 2.7 THz (the last stages of which are being fabricated at JPL) and is therefore optimized for high power operation. The multiplier features six GaAs Schottky planar diodes in a balanced configuration integrated on a GaAs membrane. Special attention was put on splitting the input power as evenly as possible among the diodes in order to ensure that no diode is overdriven. Preliminary RF tests indicate that the multiplier covers the expected bandwidth and that the efficiency is in the range 1.5-7.5 % with 100 mW of input power.

  17. Design of a Wideband 6-Anode Frequency Tripler at 300 GHz with Optimum Balance

    Science.gov (United States)

    Maestrini, Alain; Tripon-Canseliet, Charlotte; Mehdi, Imran

    2004-01-01

    We report on the design methodology of a fix-tuned split-block waveguide balanced frequency tripler working nominally at 300 GHz. It features six GaAs Schottky planar diodes in a balanced configuration. The circuit will be fabricated with JPL membrane technology in order to minimize dielectric loading and insure an accurate and uniform thickness of the substrate. The multiplier power handling is limited by the breakdown voltage of the diodes that depends on the doping level of the active layer. With six diodes, the current choice for the doping level leads to medium power handling capabilities of about 50 mW. Increasing the number of diodes to eight would be an option but would lead to increased difficulties in design and fabrication.

  18. A 540-640-GHz High-efficiency Four-anode Frequency Tripler

    Science.gov (United States)

    Maestrini, Alain; Ward, John S.; Gill, John J.; Javadi, Hamid S.; Schlecht, Erich; Tripon-Canseliet, Charlotte; Chattopadhyay, Goutam; Mehdi, Imran

    2005-01-01

    We report on the design and performance of a broad-band, high-power 540-640-GHz fix-tuned balanced frequency tripler chip that utilizes four planar Schottky anodes. The suspended strip-line circuit is fabricated with a 12-micron-thick support frame and is mounted in a split waveguide block. The chip is supported by thick beam leads that are also used to provide precise RF grounding. At room temperature, the tripler delivers 0.9-1.8 mW across the band with an estimated efficiency of 4.5%-9%. When cooled to 120 K, the tripler provides 2.0-4.2 mW across the band with an estimated efficiency of 8%-12%.

  19. Microwave noise temperature and attenuation of clouds at frequencies below 50 GHz

    Science.gov (United States)

    Slobin, S. D.

    1981-01-01

    The microwave attenuation and noise temperature effects of clouds can result in serious degradation of telecommunications link performance, especially for low-noise systems presently used in deep-space communications. Although cloud effects are generally less than rain effects, the frequent presence of clouds will cause some amount of link degradation a large portion of the time. Cloud types, water particle densities, radiative transfer, attenuation and noise temperature calculations are reviewed and examples of basic link signal to noise ratio calculations are given. Calculations for twelve different cloud models are presented for frequencies of from 1 to 50 GHz and elevation angles of 30 degrees and 90 degrees. These case results may be used as a handbook to predict noise temperature and attenuation values for known or forecast cloud conditions.

  20. A multifinger microtriode with carbon nanotubes field emission cathode operating at GHz frequency

    Science.gov (United States)

    Ulisse, G.; Brunetti, F.; Ciceroni, C.; Gemma, F.; Dispenza, M.; Fiorello, A. M.; Ricci, F.; Di Carlo, A.

    2015-05-01

    Vacuum microelectronic devices play an important role in the field of micro- and nano-electronics and they have been strongly developed in recent decades. Vacuum microelectronics are mainly based on the field emission effect and the employment of electrons in vacuum in a device with dimensions from tenths to hundredths of a micrometer. In this work, we present the development of a carbon-nanotube-based multifinger microtriode operating from 0.5 to 2 GHz. In this frequency range, a minimum RF signal gain of 5 dB is achieved. Such a device represents an optimized alternative to the standard Spindt-type microtriode. The advantage of such multifinger architecture consists in the possibility to reduce the cathode-grid capacitance by reducing the overlap between the two electrodes using a parallel patterning. This approach allows increasing the cut-off frequency of the devices with respect to the Spindt-type triode. We realized a prototype of the multifinger triode and the field emission properties have been characterized. The frequency behavior has been measured, demonstrating the possibility to amplify RF signal.

  1. Search of Continuum Solar Flare Radiation from GHz to THz Frequencies

    Science.gov (United States)

    Kaufmann, P.; Correia, E.; Giménez de Castro, C.; Hurford, G.; Lin, R. P.; Makhmutov, V. S.; Marcon, R.; Marun, A.; Raulin, J.-P.; Shih, A. Y.; Stozhkov, Y. I.; Válio, A.; Villela, T.

    2011-05-01

    The new solar burst emission spectral component showing sub-THz fluxes increasing with frequency, spectrally separated from the well known microwave component, brings serious constraints for interpretation. The knowledge of THz continuum spectral shape is essential to investigate the nature of the emission mechanisms involved. New 45 and 90 GHz solar polarimeters are being installed at El Leoncito high altitude observatory, where sub-THz (0.2 and 0.4 THz) solar flare flux data are being obtained regularly since several years. The development of THz photometers for continuum requires solutions for several technical challenges. To avoid atmospheric attenuation the THz solar observations should be carried in space or at selected frequency windows on exceptionally high sites near the South Pole. A double THz solar photometer system has been developed to operate at center frequencies of 3 and 7 THz. Golay cell sensors are used, preceded by a low pass membrane filter (f Berkeley, together with GRIPS (Gamma-Ray Imaging Polarimeter for solar flares) experiment. One test flight is planned for 2012. USA. Another balloon flight over Russia (one week) is considered between 2014-2016, in a cooperation with Moscow Lebedev Physics Institute.

  2. A multifinger microtriode with carbon nanotubes field emission cathode operating at GHz frequency.

    Science.gov (United States)

    Ulisse, G; Brunetti, F; Ciceroni, C; Gemma, F; Dispenza, M; Fiorello, A M; Ricci, F; Di Carlo, A

    2015-05-29

    Vacuum microelectronic devices play an important role in the field of micro- and nano-electronics and they have been strongly developed in recent decades. Vacuum microelectronics are mainly based on the field emission effect and the employment of electrons in vacuum in a device with dimensions from tenths to hundredths of a micrometer. In this work, we present the development of a carbon-nanotube-based multifinger microtriode operating from 0.5 to 2 GHz. In this frequency range, a minimum RF signal gain of 5 dB is achieved. Such a device represents an optimized alternative to the standard Spindt-type microtriode. The advantage of such multifinger architecture consists in the possibility to reduce the cathode-grid capacitance by reducing the overlap between the two electrodes using a parallel patterning. This approach allows increasing the cut-off frequency of the devices with respect to the Spindt-type triode. We realized a prototype of the multifinger triode and the field emission properties have been characterized. The frequency behavior has been measured, demonstrating the possibility to amplify RF signal.

  3. Tunable millimeter-wave frequency synthesis up to 100 GHz by dual-wavelength Brillouin fiber laser.

    Science.gov (United States)

    Gross, Michael C; Callahan, Patrick T; Clark, Thomas R; Novak, Dalma; Waterhouse, Rodney B; Dennis, Michael L

    2010-06-21

    We demonstrate the generation of microwave and millimeter-wave frequencies from 26 to 100 GHz by heterodyning the output modes of a dual-wavelength fiber laser based on stimulated Brillouin scattering. The output frequency is tunable in steps of 10.3 MHz, equal to the free spectral range of the resonator. The noise properties of the beat frequency indicate a microwave linewidth of <2 Hz. We discuss potential for operation into the terahertz regime.

  4. Dielectric characterization of healthy and malignant colon tissues in the 0.5-18 GHz frequency band

    Science.gov (United States)

    Fornes-Leal, A.; Garcia-Pardo, C.; Frasson, M.; Pons Beltrán, V.; Cardona, N.

    2016-10-01

    Several reports over the last few decades have shown that the dielectric properties of healthy and malignant tissues of the same body organ usually show different values. However, no intensive dielectric studies of human colon tissue have been performed, despite colon cancer’s being one of the most common types of cancer in the world. In order to provide information regarding this matter, a dielectric characterization of healthy and malignant colon tissues is presented. Measurements are performed on ex vivo surgery samples obtained from 20 patients, using an open-ended coaxial probe in the 0.5-18 GHz frequency band. Results show that the dielectric constant of colon cancerous tissue is 8.8% higher than that of healthy tissues (p  =  0.002). Besides, conductivity is about 10.6% higher, but in this case measurements do not have statistical significance (p  =  0.038). Performing an analysis per patient, the differences in dielectric constant between healthy and malignant tissues appear systematically. Particularized results for specific frequencies (500 MHz, 900 MHz, 2.45 GHz, 5 GHz, 8.5 GHz and 15 GHz) are also reported. The findings have potential application in early-stage cancer detection and diagnosis, and can be useful in developing new tools for hyperthermia treatments as well as creating electromagnetic models of healthy and cancerous tissues.

  5. Digital coherent detection of multi-gigabit 40 GHz carrier frequency radio-over-fibre signals using photonic downconversion

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Tafur Monroy, Idelfonso

    2010-01-01

    Detection of high-speed radio signals is a challenge for next generation radio-over-fibre links, requiring high bandwidth and linearity in the receiver. By using photonic downconversion in a coherent receiver, detection of high bit-rate 16-QAM signals, up to 4 Gbit/s, at a 40 GHz carrier frequency...

  6. Experimental investigation of a novel microchip laser producing synchronized dual-frequency laser pulse with an 85 GHz interval

    Science.gov (United States)

    Hu, M.; An, R. D.; Zhang, H.; Huang, Q. F.; Ge, J. H.

    2013-01-01

    A novel self-Q-switched microchip laser is introduced, which can produce synchronized dual-frequency laser pulse trains. By adopting a prepump mechanism, as well as shifting the gain curve and resonance wavelengths, the relative gains of π and σ polarization modes are adjusted, which offers an effective way to finely synchronize the laser pulses. By employing a 0.9 mm length monolithic cavity, a pair of synchronized pulse trains with a frequency separation of 85 GHz (0.32 nm) is achieved, which nearly approaches the gain bandwidth of the laser medium. Another separated cavity with a length of 2.8 mm operates in the same way for further investigation of microwave generation. A radiofrequency signal with frequency of 26.565 GHz is achieved by beat-noting of the synchronized laser pulse trains with 0.1 nm wavelength separation.

  7. Dielectric relaxation of binary polar liquid mixture measured in benzene at 10 GHz frequency

    Indian Academy of Sciences (India)

    S Sahoo; K Dutta; S Acharyya; S K Sit

    2008-03-01

    The dielectric relaxation times 's and dipole moments 's of the binary () polar liquid mixture of N,N-dimethyl acetamide (DMA) and acetone (Ac) dissolved in benzene (i) are estimated from the measured real ′ and imaginary ″ parts of complex high frequency conductivity * of the solution for different weight fractions 's of 0.0, 0.3, 0.5, 0.7 and 1.0 mole fractions of Ac and temperatures (25, 30, 35 and 40°C) respectively under 9.88 GHz electric field. 's are obtained from the ratio of slopes of ″ - and ′ - curves at → 0 as well as linear slope of ″ - ′ curves of the existing method (Murthy et al, 1989) in order to eliminate polar-polar interaction in the latter case. The calculated 's are in excellent agreement with the reported 's due to Gopalakrishna's method. 's are also estimated from slopes 's of total conductivity - curves at → 0 and the values agree well with the reported 's from G.K. method. The variation of 's and 's with of Ac reveals that solute-solute molecular association occurs within 0.0-0.3 of Ac beyond which solute-solvent molecular association is predicted. The theoretical dipole moments theo's are calculated from bond angles and bond moments to have exact 's only to show the presence of inductive, mesomeric and electromeric effects in the substituent polar groups. The thermodynamic energy parameters are estimated from ln () against 1/ linear curve from Eyring's rate theory to know the molecular dynamics of the system and to establish the fact that the mixture obeys the Debye-Smyth relaxation mechanism.

  8. 2.7-4.0 GHz PLL with dual-mode auto frequency calibration for navigation system on chip

    Institute of Scientific and Technical Information of China (English)

    陈志坚; 蔡敏; 贺小勇; 徐肯

    2016-01-01

    A 2.7−4.0 GHz dual-mode auto frequency calibration (AFC) fast locking PLL was designed for navigation system on chip (SoC). The SoC was composed of one radio frequency (RF) receiver, one baseband and several system control parts. In the proposed AFC block, both analog and digital modes were designed to complete the AFC process. In analog mode, the analog part sampled and detected the charge pump output tuning voltage, which would give the indicator to digital part to adjust the voltage control oscillator (VCO) capacitor bank. In digital mode, the digital part counted the phase lock loop (PLL) divided clock to judge whether VCO frequency was fast or slow. The analog and digital modes completed the auto frequency calibration function independently by internal switch. By designing a special switching algorithm, the switch of the digital and analog mode could be realized anytime during the lock and unlock detecting process for faster and more stable locking. This chip is fabricated in 0.13μm RF complementary metal oxide semiconductor (CMOS) process, and the VCO supports the frequency range from 2.7 to 4.0 GHz. Tested 3.96 GHz frequency phase noise is−90 dBc/Hz@100 kHz frequency offset and−120 dBc/Hz@1 MHz frequency offset. By using the analog mode in lock detection and digital mode in unlock detection, tested AFC time is less than 9μs and the total PLL lock time is less than 19μs. The SoC acquisition and tracking sensitivity are about−142 dBm and−155 dBm, respectively. The area of the proposed PLL is 0.35 mm2 and the total SoC area is about 9.6 mm2.

  9. 225-255-GHz InP DHBT Frequency Tripler MMIC Using Complementary Split-Ring Resonator

    Science.gov (United States)

    Li, Xiao; Zhang, Yong; Li, Oupeng; Sun, Yan; Lu, Haiyan; Cheng, Wei; Xu, Ruimin

    2016-10-01

    In this paper, a novel design of frequency tripler monolithic microwave integrated circuit (MMIC) using complementary split-ring resonator (CSRR) is proposed based on 0.5-μm InP DHBT process. The CSRR-loaded microstrip structure is integrated in the tripler as a part of impedance matching network to suppress the fundamental harmonic, and another frequency tripler based on conventional band-pass filter is presented for comparison. The frequency tripler based on CSRR-loaded microstrip generates an output power between -8 and -4 dBm from 228 to 255 GHz when the input power is 6 dBm. The suppression of fundamental harmonic is better than 20 dBc at 77-82 GHz input frequency within only 0.15 × 0.15 mm2 chip area of the CSRR structure on the ground layer. Compared with the frequency tripler based on band-pass filter, the tripler using CSRR-loaded microstrip obtains a similar suppression level of unwanted harmonics and higher conversion gain within a much smaller chip area. To our best knowledge, it is the first time that CSRR is used for harmonic suppression of frequency multiplier at such high frequency band.

  10. 225-255-GHz InP DHBT Frequency Tripler MMIC Using Complementary Split-Ring Resonator

    Science.gov (United States)

    Li, Xiao; Zhang, Yong; Li, Oupeng; Sun, Yan; Lu, Haiyan; Cheng, Wei; Xu, Ruimin

    2017-02-01

    In this paper, a novel design of frequency tripler monolithic microwave integrated circuit (MMIC) using complementary split-ring resonator (CSRR) is proposed based on 0.5-μm InP DHBT process. The CSRR-loaded microstrip structure is integrated in the tripler as a part of impedance matching network to suppress the fundamental harmonic, and another frequency tripler based on conventional band-pass filter is presented for comparison. The frequency tripler based on CSRR-loaded microstrip generates an output power between -8 and -4 dBm from 228 to 255 GHz when the input power is 6 dBm. The suppression of fundamental harmonic is better than 20 dBc at 77-82 GHz input frequency within only 0.15 × 0.15 mm2 chip area of the CSRR structure on the ground layer. Compared with the frequency tripler based on band-pass filter, the tripler using CSRR-loaded microstrip obtains a similar suppression level of unwanted harmonics and higher conversion gain within a much smaller chip area. To our best knowledge, it is the first time that CSRR is used for harmonic suppression of frequency multiplier at such high frequency band.

  11. A 3 to 5 GHz low-phase-noise fractional-N frequency synthesizer with adaptive frequency calibration for GSM/PCS/DCS/WCDMA transceivers

    Institute of Scientific and Technical Information of China (English)

    Pan Yaohua; Mei Niansong; Chen Hu; Huang Yumei; Hong Zhiliang

    2012-01-01

    A low-phase-noise ∑-△ fractional-N frequency synthesizer for GSM/PCS/DCS/WCDMA transceivers is presented.The voltage controlled oscillator is designed with a modified digital controlled capacitor array to extend the tuning range and minimize phase noise.A high-resolution adaptive frequency calibration technique is introduced to automatically choose frequency bands and increase phase-noise immunity.A prototype is implemented in 0.13 μm CMOS technology.The experimental results show that the designed 1.2 V wideband frequency synthesizer is locked from 3.05 to 5.17 GHz within 30μs,which covers all five required frequency bands.The measured in-band phase noise are -89,-95.5 and -101 dBc/Hz for 3.8 GHz,2 GHz and 948 MHz carriers,respectively,and accordingly the out-of-band phase noise are -121,-123 and -132 dBc/Hz at 1 MHz offset,which meet the phase-noise-mask requirements of the above-mentioned standards.

  12. Design, development and verification of the 30 and 44 GHz front-end modules for the Planck Low Frequency Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R J; Wilkinson, A; Davies, R D; Winder, W F; Roddis, N; Blackhurst, E J; Lawson, D; Lowe, S R; Baines, C; Butlin, M; Galtress, A; Shepherd, D [Jodrell Bank Centre for Astrophysics, The University of Manchester, Manchester, M13 9PL (United Kingdom); Aja, B; Artal, E [Departamento de IngenierIa de Comunicaciones, Universidad de Cantabria, Avenida de los Castros s/n. 39005 Santander (Spain); Bersanelli, M [Dipartimento di Fisica, Universita degli Studi di Milano, Via Celoria 16, 20133 Milano (Italy); Butler, R C; Cuttaia, F [INAF IASF Bologna, Via Gobetti, 101, 40129, Bologna (Italy); Castelli, C [Science and Technology Facilities Council, Swindon, Wiltshire, SN2 1SZ (United Kingdom); D' Arcangelo, O [IFP-CNR, Via Cozzi 53, Milano (Italy); Gaier, T, E-mail: Richard.Davis@manchester.ac.u [Jet Propulsion Laboratory, Pasadena, California (United States)

    2009-12-15

    We give a description of the design, construction and testing of the 30 and 44 GHz Front End Modules (FEMs) for the Low Frequency Instrument (LFI) of the Planck mission to be launched in 2009. The scientific requirements of the mission determine the performance parameters to be met by the FEMs, including their linear polarization characteristics. The FEM design is that of a differential pseudo-correlation radiometer in which the signal from the sky is compared with a 4-K blackbody load. The Low Noise Amplifier (LNA) at the heart of the FEM is based on indium phosphide High Electron Mobility Transistors (HEMTs). The radiometer incorporates a novel phase-switch design which gives excellent amplitude and phase match across the band. The noise temperature requirements are met within the measurement errors at the two frequencies. For the most sensitive LNAs, the noise temperature at the band centre is 3 and 5 times the quantum limit at 30 and 44 GHz respectively. For some of the FEMs, the noise temperature is still falling as the ambient temperature is reduced to 20 K. Stability tests of the FEMs, including a measurement of the 1/f knee frequency, also meet mission requirements. The 30 and 44 GHz FEMs have met or bettered the mission requirements in all critical aspects. The most sensitive LNAs have reached new limits of noise temperature for HEMTs at their band centres. The FEMs have well-defined linear polarization characteristics.

  13. Microwave soft x-ray microscopy for nanoscale magnetization dynamics in the 5–10 GHz frequency range

    Energy Technology Data Exchange (ETDEWEB)

    Bonetti, Stefano, E-mail: bonetti@slac.stanford.edu; Chen, Zhao [Department of Physics, Stanford University, Stanford, California 94305 (United States); Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Kukreja, Roopali [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); Spoddig, Detlef; Schöppner, Christian; Meckenstock, Ralf [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); Ollefs, Katharina [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); European Synchrotron Radiation Facility, 38043 Grenoble Cedex (France); Ney, Andreas [Institut für Experimentalphysik, Universität Duisburg-Essen, Duisburg (Germany); Solid State Physics Division, Johannes Kepler University, 4040 Linz (Austria); Pinto, Jude; Houanche, Richard; Frisch, Josef [Linear Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Stöhr, Joachim; Dürr, Hermann A. [Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); Ohldag, Hendrik [Stanford Synchrotron Radiation Laboratory, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States)

    2015-09-15

    We present a scanning transmission x-ray microscopy setup combined with a novel microwave synchronization scheme for studying high frequency magnetization dynamics at synchrotron light sources. The sensitivity necessary to detect small changes in the magnetization on short time scales and nanometer spatial dimensions is achieved by combining the excitation mechanism with single photon counting electronics that is locked to the synchrotron operation frequency. Our instrument is capable of creating direct images of dynamical phenomena in the 5-10 GHz range, with high spatial resolution. When used together with circularly polarized x-rays, the above capabilities can be combined to study magnetic phenomena at microwave frequencies, such as ferromagnetic resonance (FMR) and spin waves. We demonstrate the capabilities of our technique by presenting phase resolved images of a ∼6 GHz nanoscale spin wave generated by a spin torque oscillator, as well as the uniform ferromagnetic precession with ∼0.1° amplitude at ∼9 GHz in a micrometer-sized cobalt strip.

  14. Calibrated complex impedance of CHO cells and E. coli bacteria at GHz frequencies using scanning microwave microscopy

    Science.gov (United States)

    Tuca, Silviu-Sorin; Badino, Giorgio; Gramse, Georg; Brinciotti, Enrico; Kasper, Manuel; Oh, Yoo Jin; Zhu, Rong; Rankl, Christian; Hinterdorfer, Peter; Kienberger, Ferry

    2016-04-01

    The application of scanning microwave microscopy (SMM) to extract calibrated electrical properties of cells and bacteria in air is presented. From the S 11 images, after calibration, complex impedance and admittance images of Chinese hamster ovary cells and E. coli bacteria deposited on a silicon substrate have been obtained. The broadband capabilities of SMM have been used to characterize the bio-samples between 2 GHz and 20 GHz. The resulting calibrated cell and bacteria admittance at 19 GHz were Y cell = 185 μS + j285 μS and Y bacteria = 3 μS + j20 μS, respectively. A combined circuitry-3D finite element method EMPro model has been developed and used to investigate the frequency response of the complex impedance and admittance of the SMM setup. Based on a proposed parallel resistance-capacitance model, the equivalent conductance and parallel capacitance of the cells and bacteria were obtained from the SMM images. The influence of humidity and frequency on the cell conductance was experimentally studied. To compare the cell conductance with bulk water properties, we measured the imaginary part of the bulk water loss with a dielectric probe kit in the same frequency range resulting in a high level of agreement.

  15. The highest-frequency detection of a radio relic: 16-GHz AMI observations of the `Sausage' cluster

    CERN Document Server

    Stroe, Andra; Harwood, Jeremy J; van Weeren, Reinout; Röttgering, Huub J A; Saunders, Richard D E; Sobral, David; Perrott, Yvette C; Schammel, Michel P

    2014-01-01

    We observed the cluster CIZA J2242.8+5301 with the Arcminute Microkelvin Imager at $16$ GHz and present the first high radio-frequency detection of diffuse, non-thermal cluster emission. This cluster hosts a variety of bright, extended, steep-spectrum synchrotron-emitting radio sources, associated with the intra-cluster medium, called radio relics. Most notably, the northern, Mpc-wide, narrow relic provides strong evidence for diffusive shock acceleration in clusters. We detect a puzzling, flat-spectrum, diffuse extension of the southern relic, which is not visible in the lower radio-frequency maps. The northern radio relic is unequivocally detected and measures an integrated flux of $1.2\\pm0.3$ mJy. While the low-frequency ($<2$ GHz) spectrum of the northern relic is well represented by a power-law, it clearly steepens towards $16$ GHz. This result is inconsistent with diffusive shock acceleration predictions of ageing plasma behind a uniform shock front. The steepening could be caused by an inhomogeneous...

  16. Multi-frequency force-detected electron spin resonance in the millimeter-wave region up to 150 GHz

    Science.gov (United States)

    Ohmichi, E.; Tokuda, Y.; Tabuse, R.; Tsubokura, D.; Okamoto, T.; Ohta, H.

    2016-07-01

    In this article, a novel technique is developed for multi-frequency force-detected electron spin resonance (ESR) in the millimeter-wave region. We constructed a compact ESR probehead, in which the cantilever bending is sensitively detected by a fiber-optic Fabry-Perot interferometer. With this setup, ESR absorption of diphenyl-picrylhydrazyl radical (<1 μg) was clearly observed at multiple frequencies of up to 150 GHz. We also observed the hyperfine splitting of low-concentration Mn2+ impurities(˜0.2%) in MgO.

  17. Multi-frequency force-detected electron spin resonance in the millimeter-wave region up to 150 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Ohmichi, E., E-mail: ohmichi@harbor.kobe-u.ac.jp; Tokuda, Y.; Tabuse, R.; Tsubokura, D.; Okamoto, T. [Graduate School of Science, Kobe University, 1-1 Rokkodai-cho, Nada, Kobe 657-8501 (Japan); Ohta, H. [Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada, Kobe 657-8501 (Japan)

    2016-07-15

    In this article, a novel technique is developed for multi-frequency force-detected electron spin resonance (ESR) in the millimeter-wave region. We constructed a compact ESR probehead, in which the cantilever bending is sensitively detected by a fiber-optic Fabry-Perot interferometer. With this setup, ESR absorption of diphenyl-picrylhydrazyl radical (<1 μg) was clearly observed at multiple frequencies of up to 150 GHz. We also observed the hyperfine splitting of low-concentration Mn{sup 2+} impurities(∼0.2%) in MgO.

  18. Effects of 1.84 GHz radio-frequency electromagnetic field on sperm ...

    African Journals Online (AJOL)

    sunny t

    under this experimental condition could not affect the sperm maturation in ... As human society and technology develops fast, .... were randomly chosen for light microscopy evaluation (Leica ... transparency, neutral gum mounting, photos were taken using light ... GHz RF-EMF did not affect epididymis structure under.

  19. Microwave Absorption Properties of Ni-Foped SiC Powders in the 2-18 GHz Frequency Range

    Science.gov (United States)

    Jin, Hai-Bo; Li, Dan; Cao, Mao-Sheng; Dou, Yan-Kun; Chen, Tao; Wen, Bo; Simeon, Agathopoulos

    2011-03-01

    Ni-doped SiC powder with improved dielectric and microwave absorption properties was prepared by self-propagating high-temperature synthesis (SHS). The XRD analysis of the as-synthesized powders suggests that Ni is accommodated in the sites of Si in the lattice of SiC, which shrinks in the presence of Ni. The experimental results show an improvement in the dielectric properties of the Ni-doped SiC powder in the frequency range of 2-18 GHz. The bandwidth of the reflection loss below -10 dB is broadened from 3.04 (for pure SiC) to 4.56 GHz (for Ni-doped SiC), as well as the maximum reflection loss of produced powders from 13.34 to 22.57 dB, indicating that Ni-doped SiC could be used as an effective microwave absorption material.

  20. Microwave Absorption Properties of Ni-Foped SiC Powders in the 2-18 GHz Frequency Range

    Institute of Scientific and Technical Information of China (English)

    JIN Hai-Bo; LI Dan; CAO Mao-Sheng; DOU Yan-Kun; CHEN Tao; WEN Bo; Simeon Agathopoulos

    2011-01-01

    Ni-doped SiC powder with improved dielectric and microwave absorption properties was prepared by selfpropagating high-temperature synthesis(SHS). The XRD analysis of the asynthesized powders suggests that Ni is accommodated in the sites of Si in the lattice of SiC, which shrinks in the presence of Ni. The experimental results show an improvement in the dielectric properties of the Ni-doped SiC powder in the frequency range of 2-18 GHz. The bandwidth of the reflection loss below-10 dB is broadened from 3.04(for pure SiC) to 4.56 GHz (for Ni-doped SiC), as well as the maximum reflection loss of produced powders from 13.34 to 22.57dB, indicating that Ni-doped SiC could be used as an effective microwave absorption material.

  1. A HBAR-oscillator-based 4.596~GHz frequency source: Application to a coherent population trapping Cs vapor cell atomic clock

    CERN Document Server

    Daugey, Thomas; Martin, Gilles; Boudot, Rodolphe

    2015-01-01

    This article reports on the design and characterization of a high-overtone bulk acoustic wave resonator (HBAR)-oscillator-based 4.596~GHz frequency source. A 2.298~GHz signal, generated by an oscillator constructed around a thermally-controlled two-port AlN-sapphire HBAR resonator with a Q-factor of 24000 at 68$^{\\circ}$C, is frequency multiplied by 2 to 4.596~GHz, half of the Cs atom clock frequency. The temperature coefficient of frequency (TCF) of the HBAR is measured to be $-23$~ppm/$^{\\circ}$C at 2.298~GHz. The measured phase noise of the 4.596~GHz source is $-105$~dBrad$^2$/Hz at 1~kHz offset and $-150$~dBrad$^2$/Hz at 100~kHz offset. The 4.596~GHz output signal is used as a local oscillator (LO) in a laboratory-prototype Cs microcell-based coherent population trapping (CPT) atomic clock. The signal is stabilized onto the atomic transition frequency by tuning finely a voltage-controlled phase shifter (VCPS) implemented in the 2.298~GHz HBAR-oscillator loop, preventing the need for a high-power-consuming...

  2. Effective conductivity and permittivity of unsaturated porous materials in the frequency range 1 mHz-1GHz.

    Science.gov (United States)

    Revil, A

    2013-01-01

    A model combining low-frequency complex conductivity and high-frequency permittivity is developed in the frequency range from 1 mHz to 1 GHz. The low-frequency conductivity depends on pore water and surface conductivities. Surface conductivity is controlled by the electrical diffuse layer, the outer component of the electrical double layer coating the surface of the minerals. The frequency dependence of the effective quadrature conductivity shows three domains. Below a critical frequency fp , which depends on the dynamic pore throat size Λ, the quadrature conductivity is frequency dependent. Between fp and a second critical frequency fd , the quadrature conductivity is generally well described by a plateau when clay minerals are present in the material. Clay-free porous materials with a narrow grain size distribution are described by a Cole-Cole model. The characteristic frequency fd controls the transition between double layer polarization and the effect of the high-frequency permittivity of the material. The Maxwell-Wagner polarization is found to be relatively negligible. For a broad range of frequencies below 1 MHz, the effective permittivity exhibits a strong dependence with the cation exchange capacity and the specific surface area. At high frequency, above the critical frequency fd , the effective permittivity reaches a high-frequency asymptotic limit that is controlled by the two Archie's exponents m and n like the low-frequency electrical conductivity. The unified model is compared with various data sets from the literature and is able to explain fairly well a broad number of observations with a very small number of textural and electrochemical parameters. It could be therefore used to interpret induced polarization, induction-based electromagnetic methods, and ground penetrating radar data to characterize the vadose zone.

  3. Polarization-insensitive FSS-based perfect metamaterial absorbers for GHz and THz frequencies

    National Research Council Canada - National Science Library

    Cumali Sabah; Furkan Dincer; Muharrem Karaaslan; Emin Unal; Oguzhan Akgol

    2014-01-01

      New perfect frequency selective surface (FSS) metamaterial absorbers (MAs) based on resonator with dielectric configuration are numerically presented and investigated for both microwave and terahertz frequency ranges...

  4. Complex permeability and permittivity variation of carbonyl iron rubber in the frequency range of 2 to 18 GHz

    Directory of Open Access Journals (Sweden)

    Adriana Medeiros Gama

    2010-04-01

    Full Text Available The complex dielectric permittivity (e and magnetic permeability (m of Radar Absorbing Materials (RAM based on metallic magnetic particles (carbonyl iron particles embedded in a dielectric matrix (silicon rubber have been studied in the frequency range of 2 to 18 GHz. The relative permeability and permittivity of carbonyl iron-silicon composites for various mass fractions are measured by the transmission/reflection method using a vector network analyzer. The concentration dependence of permittivity and permeability on the frequency is analyzed. In a general way, the results show that e´ parameter shows a more significant variation among the evaluated parameters (e”, m”, m’. The comparison of dielectric and magnetic loss tangents (e”/e” and m”/m’, respectively shows more clearly the variation of both parameters (e and m according to the frequency. It is also observed that higher carbonyl iron content fractions favor both dielectric and magnetic loss tangents.

  5. Digital coherent detection of multi-gigabit 40 GHz carrier frequency radio-over-fiber signals using photonic downconversion

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Tafur Monroy, Idelfonso

    Detection of high speed radio signals is a challenge for next generation radio-over-fiber links, requiring high bandwidth and linearity in the receiver. By using photonic downconversion in a coherent receiver, it is possible to detect signals exceeding the electrical bandwidth of the receiver......, by performing the mixing of the radio signal with a free-running local oscillator in the optical domain. In this paper we present the experimental emonstration of high bitrate 16-QAM signal detection, up to 4 Gb/s, at 40 GHz carrier frequency, using low bandwidth electronics....

  6. 60 GHz antenna measurement setup using a VNA without external frequency conversion

    DEFF Research Database (Denmark)

    Popa, Paula Irina; Pivnenko, Sergey; Nielsen, Jeppe Majlund;

    2014-01-01

    and phase, 0.06 dB and 6 degrees peak-to-peak deviations over 4 hours. A PNF measurement of a 25 dBi Standard Gain Horn was carried out and the results were compared to those from the DTU-ESA Spherical Near-Field Facility with a good agreement in the validity region. Uncertainty investigations regarding...... cable flexing effects at 60 GHz have shown that these introduce an uncertainty of about 0.02 dB (1 sigma) around the main beam region indicating a very good performance of the PNF setup....

  7. Measures of maximum magnetic field in 3 GHz radio frequency superconducting cavities; Mesures du gradient accelerateur maximum dans des cavites supraconductrices en regime impulsionnel a 3 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Catherine [Paris-11 Univ., 91 Orsay (France)

    2000-01-19

    Theoretical models have shown that the maximum magnetic field in radio frequency superconducting cavities is the superheating field H{sub sh}. For niobium, H{sub sh} is 25 - 30% higher than the thermodynamical H{sub c} field: H{sub sh} within (240 - 274) mT. However, the maximum magnetic field observed so far is in the range H{sub c,max} = 152 mT for the best 1.3 GHz Nb cavities. This field is lower than the critical field H{sub c1} above which the superconductor breaks up into divided normal and superconducting zones (H{sub c1}{<=}H{sub c}). Thermal instabilities are responsible for this low value. In order to reach H{sub sh} before thermal breakdown, high power short pulses are used. The cavity needs then to be strongly over-coupled. The dedicated test bed has been built from the collaboration between Istituto Nazionale di Fisica Nucleare (INFN) - Sezione di Genoa, and the Service d'Etudes et Realisation d'Accelerateurs (SERA) of Laboratoire de l'Accelerateur Lineaire (LAL). The maximum magnetic field, H{sub rf,max}, measurements on INFN cavities give lower results than the theoretical speculations and are in agreement with previous results. The superheating magnetic fields is linked to the magnetic penetration depth. This superconducting characteristic length can be used to determine the quality of niobium through the ratio between the resistivity measured at 300 K and 4.2 K in the normal conducting state (RRR). Results have been compared to previous ones and agree pretty well. They show that the RRR measured on cavities is superficial and lower than the RRR measured on samples which concerns the volume. (author)

  8. High quality factor manganese-doped aluminum lumped-element kinetic inductance detectors sensitive to frequencies below 100 GHz

    Science.gov (United States)

    Jones, G.; Johnson, B. R.; Abitbol, M. H.; Ade, P. A. R.; Bryan, S.; Cho, H.-M.; Day, P.; Flanigan, D.; Irwin, K. D.; Li, D.; Mauskopf, P.; McCarrick, H.; Miller, A.; Song, Y. R.; Tucker, C.

    2017-05-01

    Aluminum lumped-element kinetic inductance detectors (LEKIDs) sensitive to millimeter-wave photons have been shown to exhibit high quality factors, making them highly sensitive and multiplexable. The superconducting gap of aluminum limits aluminum LEKIDs to photon frequencies above 100 GHz. Manganese-doped aluminum (Al-Mn) has a tunable critical temperature and could therefore be an attractive material for LEKIDs sensitive to frequencies below 100 GHz if the internal quality factor remains sufficiently high when manganese is added to the film. To investigate, we measured some of the key properties of Al-Mn LEKIDs. A prototype eight-element LEKID array was fabricated using a 40 nm thick film of Al-Mn deposited on a 500 μm thick high-resistivity, float-zone silicon substrate. The manganese content was 900 ppm, the measured Tc = 694 ± 1mK, and the resonance frequencies were near 150 MHz. Using measurements of the forward scattering parameter S21 at various bath temperatures between 65 and 250 mK, we determined that the Al-Mn LEKIDs we fabricated have internal quality factors greater than 2 × 105, which is high enough for millimeter-wave astrophysical observations. In the dark conditions under which these devices were measured, the fractional frequency noise spectrum shows a shallow slope that depends on bath temperature and probe tone amplitude, which could be two-level system noise. The anticipated white photon noise should dominate this level of low-frequency noise when the detectors are illuminated with millimeter-waves in future measurements. The LEKIDs responded to light pulses from a 1550 nm light-emitting diode, and we used these light pulses to determine that the quasiparticle lifetime is 60 μs.

  9. A 12.5 GHz-spaced optical frequency comb spanning >400 nm for near-infrared astronomical spectrograph calibration.

    Science.gov (United States)

    Quinlan, F; Ycas, G; Osterman, S; Diddams, S A

    2010-06-01

    A 12.5 GHz-spaced optical frequency comb locked to a global positioning system disciplined oscillator for near-infrared (IR) spectrograph calibration is presented. The comb is generated via filtering a 250 MHz-spaced comb. Subsequent nonlinear broadening of the 12.5 GHz comb extends the wavelength range to cover 1380-1820 nm, providing complete coverage over the H-band transmission window of earth's atmosphere. Finite suppression of spurious sidemodes, optical linewidth, and instability of the comb has been examined to estimate potential wavelength biases in spectrograph calibration. Sidemode suppression varies between 20 and 45 dB, and the optical linewidth is approximately 350 kHz at 1550 nm. The comb frequency uncertainty is bounded by +/-30 kHz (corresponding to a radial velocity of +/-5 cm/s), limited by the global positioning system disciplined oscillator reference. These results indicate that this comb can readily support radial velocity measurements below 1 m/s in the near IR.

  10. The contribution of microbunching instability to solar flare emission in the GHz to THz range of frequencies

    CERN Document Server

    Klopf, J Michael; Raulin, Jean-Pierre; Szpigel, Sérgio

    2014-01-01

    Recent solar flare observations in the sub-THz range have provided evidence of a new spectral component with fluxes increasing for larger frequencies, separated from the well-known microwave emission that maximizes in the GHz range. Suggested interpretations explain the THz spectral component, but do not account for the simultaneous microwave component. We present a mechanism for producing the observed double-spectra. Based on coherent enhancement of synchrotron emission at long wavelengths in laboratory accelerators, we consider how similar processes may occur within a solar flare. The instability known as microbunching arises from perturbations that produce electron beam density modulations, giving rise to broadband coherent synchrotron emission at wavelengths comparable to the characteristic size of the microbunch structure. The spectral intensity of this coherent synchrotron radiation (CSR) can far exceed that of the incoherent synchrotron radiation (ISR), which peaks at higher frequency, thus producing a...

  11. Demonstration of on-sky calibration of astronomical spectra using a 25 GHz near-IR laser frequency comb.

    Science.gov (United States)

    Ycas, Gabriel G; Quinlan, Franklyn; Diddams, Scott A; Osterman, Steve; Mahadevan, Suvrath; Redman, Stephen; Terrien, Ryan; Ramsey, Lawrence; Bender, Chad F; Botzer, Brandon; Sigurdsson, Steinn

    2012-03-12

    We describe and characterize a 25 GHz laser frequency comb based on a cavity-filtered erbium fiber mode-locked laser. The comb provides a uniform array of optical frequencies spanning 1450 nm to 1700 nm, and is stabilized by use of a global positioning system referenced atomic clock. This comb was deployed at the 9.2 m Hobby-Eberly telescope at the McDonald Observatory where it was used as a radial velocity calibration source for the fiber-fed Pathfinder near-infrared spectrograph. Stellar targets were observed in three echelle orders over four nights, and radial velocity precision of ∼10 m/s (∼6 MHz) was achieved from the comb-calibrated spectra.

  12. Digital predistortion of 75-110 GHz W-band frequency multiplier for fiber wireless short range access systems.

    Science.gov (United States)

    Zhao, Ying; Deng, Lei; Pang, Xiaodan; Yu, Xianbin; Zheng, Xiaoping; Zhang, Hanyi; Monroy, Idelfonso Tafur

    2011-12-12

    We present a W-band fiber-wireless transmission system based on a nonlinear frequency multiplier for high-speed wireless short range access applications. By implementing a baseband digital signal predistortion scheme, intensive nonlinear distortions induced in a sextuple frequency multiplier can be effectively pre-compensated. Without using costly W-band components, a transmission system with 26 km fiber and 4 m wireless transmission operating at 99.6 GHz is experimentally validated. Adjacent-channel power ratio (ACPR) improvements for IQ-modulated vector signals are guaranteed and transmission performances for fiber and wireless channels are studied. This W-band predistortion technique is a promising candidate for applications in high capacity wireless-fiber access systems.

  13. Demonstration of On-Sky Calibration of Astronomical Spectra using a 25 GHz near-IR Laser Frequency Comb

    CERN Document Server

    Ycas, Gabriel G; Diddams, Scott A; Osterman, Steve; Mahadevan, Suvrath; Redman, Stephen; Terrien, Ryan; Ramsey, Lawrence; Bender, Chad F; Botzer, Brandon; Sigurdsson, Steinn

    2012-01-01

    We describe and characterize a 25 GHz laser frequency comb based on a cavity-filtered erbium fiber mode-locked laser. The comb provides a uniform array of optical frequencies spanning 1450 nm to 1700 nm, and is stabilized by use of a global positioning system referenced atomic clock. This comb was deployed at the 9.2 m Hobby-Eberly telescope at the McDonald Observatory where it was used as a radial velocity calibration source for the fiber-fed Pathfinder near-infrared spectrograph. Stellar targets were observed in three echelle orders over four nights, and radial velocity precision of ~10 m/s (~6 MHz) was achieved from the comb-calibrated spectra.

  14. Digital predistortion of 75–110 GHz W-band frequency multiplier for fiber wireless short range access systems

    DEFF Research Database (Denmark)

    Zhao, Ying; Deng, Lei; Pang, Xiaodan

    2011-01-01

    We present a W-band fiber-wireless transmission system based on a nonlinear frequency multiplier for high-speed wireless short range access applications. By implementing a baseband digital signal predistortion scheme, intensive nonlinear distortions induced in a sextuple frequency multiplier can...... be effectively pre-compensated. Without using costly W-band components, a transmission system with 26km fiber and 4m wireless transmission operating at 99.6GHz is experimentally validated. Adjacent-channel power ratio (ACPR) improvements for IQ-modulated vector signals are guaranteed and transmission...... performances for fiber and wireless channels are studied. This W-band predistortion technique is a promising candidate for applications in high capacity wireless-fiber access systems....

  15. Planck intermediate results: VII. Statistical properties of infrared and radio extragalactic sources from the Planck Early Release Compact Source Catalogue at frequencies between 100 and 857 GHz

    DEFF Research Database (Denmark)

    Delabrouille, J.; Ganga, K.; Giraud-Héraud, Y.

    2013-01-01

    of the Planck High Frequency Instrument, all the sources have been classified as either dust-dominated (infrared galaxies) or synchrotron-dominated (radio galaxies) on the basis of their spectral energy distributions (SED). Our sample is thus complete, flux-limited and color-selected to differentiate between......We make use of the Planck all-sky survey to derive number counts and spectral indices of extragalactic sources-infrared and radio sources-from the Planck Early Release Compact Source Catalogue (ERCSC) at 100 to 857 GHz (3 mm to 350 μm). Three zones (deep, medium and shallow) of approximately...... the two populations. We find an approximately equal number of synchrotron and dusty sources between 217 and 353 GHz; at 353 GHz or higher (or 217 GHz and lower) frequencies, the number is dominated by dusty (synchrotron) sources, as expected. For most of the sources, the spectral indices are also derived...

  16. A high-overtone bulk acoustic wave resonator-oscillator-based 4.596 GHz frequency source: Application to a coherent population trapping Cs vapor cell atomic clock

    Energy Technology Data Exchange (ETDEWEB)

    Daugey, Thomas; Friedt, Jean-Michel; Martin, Gilles; Boudot, Rodolphe [FEMTO-ST, CNRS, UFC, 26 chemin de l’Epitaphe 25030 Besançon Cedex (France)

    2015-11-15

    This article reports on the design and characterization of a high-overtone bulk acoustic wave resonator (HBAR)-oscillator-based 4.596 GHz frequency source. A 2.298 GHz signal, generated by an oscillator constructed around a thermally controlled two-port aluminum nitride-sapphire HBAR resonator with a Q-factor of 24 000 at 68 °C, is frequency multiplied by 2–4.596 GHz, half of the Cs atom clock frequency. The temperature coefficient of frequency of the HBAR is measured to be −23 ppm/ °C at 2.298 GHz. The measured phase noise of the 4.596 GHz source is −105 dB rad{sup 2}/Hz at 1 kHz offset and −150 dB rad{sup 2}/Hz at 100 kHz offset. The 4.596 GHz output signal is used as a local oscillator in a laboratory-prototype Cs microcell-based coherent population trapping atomic clock. The signal is stabilized onto the atomic transition frequency by tuning finely a voltage-controlled phase shifter implemented in the 2.298 GHz HBAR-oscillator loop, preventing the need for a high-power-consuming direct digital synthesis. The short-term fractional frequency stability of the free-running oscillator is 1.8 × 10{sup −9} at one second integration time. In locked regime, the latter is improved in a preliminary proof-of-concept experiment at the level of 6.6 × 10{sup −11} τ{sup −1/2} up to a few seconds and found to be limited by the signal-to-noise ratio of the detected CPT resonance.

  17. A stabilized 18 GHz chip-scale optical frequency comb at 2.8x10-16 relative inaccuracy

    CERN Document Server

    Huang, S -W; Yu, M; McGuyer, B H; Kwong, D -L; Zelevinsky, T; Wong, C W

    2015-01-01

    Optical frequency combs, coherent light sources that connect optical frequencies with microwave oscillations, have become the enabling tool for precision spectroscopy, optical clockwork and attosecond physics over the past decades. Current benchmark systems are self-referenced femtosecond mode-locked lasers, but four-wave-mixing in high-Q resonators have emerged as alternative platforms. Here we report the generation and full stabilization of CMOS-compatible optical frequency combs. The spiral microcomb's two degrees-of-freedom, one of the comb line and the native 18 GHz comb spacing, are first simultaneously phase-locked to known optical and microwave references. Second, with pump power control, active comb spacing stabilization improves the long-term stability by six orders-of-magnitude, reaching an instrument-limited 3.6 mHz/sqrt(t) residual instability. Third, referencing thirty-three of the nitride frequency comb lines against a fiber comb, we demonstrate the comb tooth-to-tooth frequency relative inaccu...

  18. On the averaging area for incident power density for human exposure limits at frequencies over 6 GHz

    Science.gov (United States)

    Hashimoto, Yota; Hirata, Akimasa; Morimoto, Ryota; Aonuma, Shinta; Laakso, Ilkka; Jokela, Kari; Foster, Kenneth R.

    2017-04-01

    Incident power density is used as the dosimetric quantity to specify the restrictions on human exposure to electromagnetic fields at frequencies above 3 or 10 GHz in order to prevent excessive temperature elevation at the body surface. However, international standards and guidelines have different definitions for the size of the area over which the power density should be averaged. This study reports computational evaluation of the relationship between the size of the area over which incident power density is averaged and the local peak temperature elevation in a multi-layer model simulating a human body. Three wave sources are considered in the frequency range from 3 to 300 GHz: an ideal beam, a half-wave dipole antenna, and an antenna array. 1D analysis shows that averaging area of 20 mm  ×  20 mm is a good measure to correlate with the local peak temperature elevation when the field distribution is nearly uniform in that area. The averaging area is different from recommendations in the current international standards/guidelines, and not dependent on the frequency. For a non-uniform field distribution, such as a beam with small diameter, the incident power density should be compensated by multiplying a factor that can be derived from the ratio of the effective beam area to the averaging area. The findings in the present study suggest that the relationship obtained using the 1D approximation is applicable for deriving the relationship between the incident power density and the local temperature elevation.

  19. The faint source population at 15.7 GHz - III. A high-frequency study of HERGs and LERGs

    CERN Document Server

    Whittam, Imogen H; Green, David A; Jarvis, Matt J

    2016-01-01

    A complete sample of 96 faint ($S > 0.5$ mJy) radio galaxies is selected from the Tenth Cambridge (10C) survey at 15.7~GHz. Optical spectra are used to classify 17 of the sources as high-excitation or low-excitation radio galaxies (HERGs and LERGs respectively), for the remaining sources three other methods are used; these are optical compactness, X-ray observations and mid-infrared colour--colour diagrams. 32 sources are HERGs and 35 are LERGs while the remaining 29 sources could not be classified. We find that the 10C HERGs tend to have higher 15.7-GHz flux densities, flatter spectra, smaller linear sizes and be found at higher redshifts than the LERGs. This suggests that the 10C HERGs are more core dominated than the LERGs. Lower-frequency radio images, linear sizes and spectral indices are used to classify the sources according to their radio morphology; 18 are Fanaroff and Riley type I or II sources, a further 13 show some extended emission, and the remaining 65 sources are compact and are referred to as...

  20. Sensing glucose concentrations at GHz frequencies with a fully embedded Biomicro-electromechanical system (BioMEMS).

    Science.gov (United States)

    Birkholz, M; Ehwald, K-E; Basmer, T; Kulse, P; Reich, C; Drews, J; Genschow, D; Haak, U; Marschmeyer, S; Matthus, E; Schulz, K; Wolansky, D; Winkler, W; Guschauski, T; Ehwald, R

    2013-06-28

    The progressive scaling in semiconductor technology allows for advanced miniaturization of intelligent systems like implantable biosensors for low-molecular weight analytes. A most relevant application would be the monitoring of glucose in diabetic patients, since no commercial solution is available yet for the continuous and drift-free monitoring of blood sugar levels. We report on a biosensor chip that operates via the binding competition of glucose and dextran to concanavalin A. The sensor is prepared as a fully embedded micro-electromechanical system and operates at GHz frequencies. Glucose concentrations derive from the assay viscosity as determined by the deflection of a 50 nm TiN actuator beam excited by quasi-electrostatic attraction. The GHz detection scheme does not rely on the resonant oscillation of the actuator and safely operates in fluidic environments. This property favorably combines with additional characteristics-(i) measurement times of less than a second, (ii) usage of biocompatible TiN for bio-milieu exposed parts, and (iii) small volume of less than 1 mm(3)-to qualify the sensor chip as key component in a continuous glucose monitor for the interstitial tissue.

  1. Frequency dependence of electron spin relaxation times in aqueous solution for a nitronyl nitroxide radical and perdeuterated-tempone between 250 MHz and 34 GHz.

    Science.gov (United States)

    Biller, Joshua R; Meyer, Virginia M; Elajaili, Hanan; Rosen, Gerald M; Eaton, Sandra S; Eaton, Gareth R

    2012-12-01

    Electron spin relaxation times of perdeuterated tempone (PDT) 1 and of a nitronyl nitroxide (2-(4-carboxy-phenyl)-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl) 2 in aqueous solution at room temperature were measured by 2-pulse electron spin echo (T(2)) or 3-pulse inversion recovery (T(1)) in the frequency range of 250 MHz to 34 GHz. At 9 GHz values of T(1) measured by long-pulse saturation recovery were in good agreement with values determined by inversion recovery. Below 9 GHz for 1 and below 1.5 GHz for 2,T(1)~T(2), as expected in the fast tumbling regime. At higher frequencies T(2) was shorter than T(1) due to incomplete motional averaging of g and A anisotropy. The frequency dependence of 1/T(1) is modeled as the sum of spin rotation, modulation of g and A-anisotropy, and a thermally-activated process that has maximum contribution at about 1.5 GHz. The spin lattice relaxation times for the nitronyl nitroxide were longer than for PDT by a factor of about 2 at 34 GHz, decreasing to about a factor of 1.5 at 250 MHz. The rotational correlation times, τ(R) are calculated to be 9 ps for 1 and about 25 ps for 2. The longer spin lattice relaxation times for 2 than for 1 at 9 and 34 GHz are due predominantly to smaller contributions from spin rotation that arise from slower tumbling. The smaller nitrogen hyperfine couplings for the nitronyl 2 than for 1 decrease the contribution to relaxation due to modulation of A anisotropy. However, at lower frequencies the slower tumbling of 2 results in a larger value of ωτ(R) (ω is the resonance frequency) and larger values of the spectral density function, which enhances the contribution from modulation of anisotropic interactions for 2 to a greater extent than for 1.

  2. Dual-frequency comb generation with differing GHz repetition rates by parallel Fabry-Perot cavity filtering of a single broadband frequency comb source

    Science.gov (United States)

    Mildner, Jutta; Meiners-Hagen, Karl; Pollinger, Florian

    2016-07-01

    We present a dual-comb-generator based on a coupled Fabry-Perot filtering cavity doublet and a single seed laser source. By filtering a commercial erbium-doped fiber-based optical frequency comb with CEO-stabilisation and 250 MHz repetition rate, two broadband coherent combs of different repetition rates in the GHz range are generated. The filtering doublet consists of two Fabry-Perot cavities with a tunable spacing and Pound-Drever-Hall stabilisation scheme. As a prerequisite for the development of such a filtering unit, we present a method to determine the actual free spectral range and transmission bandwidth of a Fabry-Perot cavity in situ. The transmitted beat signal of two diode lasers is measured as a function of their tunable frequency difference. Finally, the filtering performance and resulting beat signals of the heterodyned combs are discussed as well as the optimisation measures of the whole system.

  3. Fabrication and materials for magneto-photonic assemblies for high-gain antenna applications at GHz frequencies

    Science.gov (United States)

    Zhang, Lanlin

    Recent magnetic photonic assembly (MPA) designs for high-gain antennas contain arrays of low-loss, anisotropic dielectrics and ferrimagnetic materials. Anisotropic dielectrics (AD) are fabricated from laminates, which consist of two ceramics with largely different permittivity and low dielectric losses at GHz frequencies. High gain has been demonstrated in a prototype antenna with 2 sets of 3 mutually rotated AD layers. These layers were made from laminates of commercially available alpha-Al2O3 and Nd-doped barium titanate. Equivalent permittivity tensors and loss tangents (tan delta˜1.9x10-3) were characterized using a resonant cavity based approach, coupled with a finite-element method (FEM) full-wave solver. To enable further minimization of dielectric loss (tan delta), dense high-purity alpha-Al2O3 and TiO2 were prepared starting from colloidally stabilizing the powders in aqueous HNO3 or NH3. After colloidal filtration and sintering, alpha-Al 2O3 with >97.9% density was achieved at a sintering temperature of 1300°C, and TiO2 with >99.5% density was obtained at 1000°C. These low sintering temperatures are ascribed to excellent compact homogeneity. TiO2 was obtained with tan delta of 1.4x10-4 at 6.4 GHz at room temperature. This relatively low value is attributed to the homogeneous dense microstructure with 2.2 mum grain size. Al 3+ was doped into TiO2 using a modified infiltration method to compensate for the effect of Ti4+ reduction. A homogeneous microstructure and doping concentration were also observed in the doped dense TiO2. Substituted Y3Fe5O12 (YIG) garnet was chosen as the ferrimagnetic (F) component, due to its pronounced Faraday rotation effect and potentially low magnetic and dielectric loss. Phase pure garnet was prepared by using the citric-gel method. The magnetic properties were studied for Ca,V,Zr-substituted YIG (CVZG) and as-prepared particle morphology. Compacts of CVZG submicron particles were found to possess a low loss at GHz

  4. ELISA: a cryocooled 10 GHz oscillator with 10-15 frequency stability

    CERN Document Server

    Grop, S; Bazin, N; Kersale, Y; Rubiola, E; Langham, C; Oxborrow, M; Clapton, D; Walker, S; De Vicente, J; Giordano, V

    2009-01-01

    This article reports the design, the breadboarding and the validation of an ultra-stable Cryogenic Sapphire Oscillator operated in an autonomous cryocooler. The objective of this project was to demonstrate the feasibility of a frequency stability of 3x10-15 between 1 s and 1,000 s for the European Space Agency deep space stations. This represents the lowest fractional frequency instability ever achieved with cryocoolers. The preliminary results presented in this paper validate the design we adopted for the sapphire resonator, the cold source and the oscillator loop.

  5. ELISA: a cryocooled 10 GHz oscillator with 10(-15) frequency stability.

    Science.gov (United States)

    Grop, S; Bourgeois, P Y; Bazin, N; Kersalé, Y; Rubiola, E; Langham, C; Oxborrow, M; Clapton, D; Walker, S; De Vicente, J; Giordano, V

    2010-02-01

    This article reports the design, the breadboarding, and the validation of an ultrastable cryogenic sapphire oscillator operated in an autonomous cryocooler. The objective of this project was to demonstrate the feasibility of a frequency stability of 3x10(-15) between 1 and 1000 s for the European Space Agency deep space stations. This represents the lowest fractional frequency instability ever achieved with cryocoolers. The preliminary results presented in this paper validate the design we adopted for the sapphire resonator, the cold source, and the oscillator loop.

  6. Laser frequency locking with 46 GHz offset using an electro-optic modulator for magneto-optical trapping of francium atoms

    CERN Document Server

    Harada, K; Ezure, S; Kato, K; Hayamizu, T; Kawamura, H; Inoue, T; Arikawa, H; Ishikawa, T; Aoki, T; Uchiyama, A; Sakamoto, K; Ito, S; Itoh, M; Ando, S; Hatakeyama, A; Hatanaka, K; Imai, K; Murakami, T; Nataraj, H S; Shimizu, Y; Sato, T; Wakasa, T; Yoshida, H P; Sakemi, Y

    2016-01-01

    We demonstrated a frequency offset locking between two laser sources using a waveguide-type electro-optic modulator (EOM) with 10th-order sidebands for magneto-optical trapping of Fr atoms. The frequency locking error signal was successfully obtained by performing delayed self-homodyne detection of the beat signal between the repumping frequency and the 10th-order sideband component of the trapping light. Sweeping the trapping-light and repumping-light frequencies with keeping its frequency difference of 46 GHz was confirmed over 1 GHz by monitoring the Doppler absorption profile of I2. This technique enables us to search for a resonance frequency of magneto-optical trapping of Fr.

  7. High Current Multi-finger InGaAs/InP Double Heterojunction Bipolar Transistor with the Maximum Oscillation Frequency 253 GHz

    Institute of Scientific and Technical Information of China (English)

    JIN Zhi; SU Yong-bo; CHENG Wei; LIU Xin-Yu; XU An-Huai; QI Ming

    2008-01-01

    @@ A four-finger InGaAs/InP double heterojunction bipolar transistor is designed and fabricated successfully by using planarization technology. The emitter area of each finger is 1 × 15 μm2. The breakdown voltage is more than 7V, the maximum collector current could be more than 100mA. The current gain cutoff frequency is as high as 155 GHz and the maximum oscillation frequency reaches 253 GHz. The heterostructure bipolar transistor can offer more than 70mW class-A maximum output power at W band and the maximum power density can be as high as 1.2 W/mm.

  8. Measurements of the superconducting proximity effect in Pd/Al NS bilayers at GHz frequencies

    Science.gov (United States)

    Nersisyan, Ani; Manenti, Riccardo; Peterer, Michael; Magnusson, Einar; Tancredi, Giovanna; Patterson, Andrew; Leek, Peter

    The superconducting proximity effect, well known since the 1960s, describes superconductivity in the case of a superconductor contacted to a normal metal, and is typically studied experimentally using transport techniques such as tunneling spectroscopy. Here we will present studies of the superconducting proximity effect in thin film palladium/aluminum NS bilayers using microwave frequency lumped element LC resonators. Measurements of the resonance frequency and quality factor as a function of temperature and film thickness reveal properties of the NS bilayers such as the critical temperature and penetration depth. Our results should be useful for understanding losses in superconducting quantum circuits that incorporate thin normal layers, and, in the particular case of Pd, should aid in design of hybrid superconducting quantum devices incorporating carbon nanotubes with high contact transparency

  9. Effects of low intensity electromagnetic irradiation of 70.6 and 73 GHz frequencies and antibiotics on energy-dependent proton and potassium ion transport by E. coli.

    Science.gov (United States)

    Torgomyan, H

    2012-12-01

    The effects of low intensity (flux capacity 0.06 mW/cm2) coherent electromagnetic irradiation (EMI) of 70.6 and 73 GHz frequencies and their combined effects with antibiotics--ceftriaxone or kanamycin (0.4 or 15 microM, correspondingly) on E. coli K12 growth and survival have been reported previously. To further study the effects of EMI and antibiotics and mechanisms, decrease in overall energy (glucose)-dependent H+ and K+ fluxes across the cell membrane was investigated in E. coli. The depression of H+ and K+ fluxes rate was maximally achieved with the 73 GHz frequency. The EMI strengthened the effect of N,N'-dicyclohexycarbodiimide (DCCD, an inhibitor of the F0F1-ATPase). The 73 GHz EMI had more influence on H+ efflux inhibition, whereas 70.6 GHz on K+ influx. Also, EMI strengthened the depressive effects of ceftriaxone and kanamycin on the overall and DCCD-inhibited H+ and K+ fluxes. The 73 GHz EMI strengthened the effect of ceftriaxone on both ions fluxes. Kanamycin depressed H+ efflux more as compared to ceftriaxone, which was also strengthened with EMI. The results of E. coli H+ and K+ transport systems activities depression by irradiation and the irradiation effect on DCCD and antibiotics action indicated the EMI and antibiotics causing primary changes in the bacterial membrane.

  10. Evaluation of the maximum permissible level of low-intensity electromagnetic radiation at mobile connection frequency (1 GHz) by changes in motor activity of Spirostomum Ambiguum.

    Science.gov (United States)

    Sarapultseva, E I; Igolkina, J V; Litovchenko, A V

    2009-04-01

    Electromagnetic radiation at the mobile connection frequency (1 GHz) at maximum energy flow density (10 microW/cm(2)) permitted in Russia causes serious functional disorders in the studied unicellular hydrobionts infusoria Spirostomum ambiguum: reduction of their spontaneous motor activity. The form of biological reaction is uncommon: the effect is threshold, overall, and does not depend on the duration of microwave exposure.

  11. Numerical investigation of In0.23Ga0.77As-based planar Gunn diodes with fundamental frequency up to 116 GHz

    Science.gov (United States)

    Li, B.; Liu, H. X.; Wen, C.

    2015-09-01

    The current capability and frequency of In0.23Ga0.77As-based planar Gunn diode have been studied using numerical simulation. Our simulated results are well in agreement with the experimental observation with fundamental frequency operating up to 116 GHz. Through the Fast Fourier transform algorithm, it has been revealed that oscillating frequency tunes downward slightly with increased applied voltage above threshold voltage, and a second-harmonic frequency is observed at 233 GHz for 1.45-μm channel length. This structure provides feasibility of generating a tunable millimeter wave or terahertz wave source and has an overwhelming advantage over equivalent traditional vertical structure because of increased facilitated integration and flexibility.

  12. Numerical investigation of In{sub 0.23}Ga{sub 0.77}As-based planar Gunn diodes with fundamental frequency up to 116 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Li, B.; Wen, C. [Southwest University of Science and Technology, School of Science, Mianyang (China); Liu, H.X. [Xidian University, School of Microelectronics, Xi' an (China)

    2015-09-15

    The current capability and frequency of In{sub 0.23}Ga{sub 0.77}As-based planar Gunn diode have been studied using numerical simulation. Our simulated results are well in agreement with the experimental observation with fundamental frequency operating up to 116 GHz. Through the Fast Fourier transform algorithm, it has been revealed that oscillating frequency tunes downward slightly with increased applied voltage above threshold voltage, and a second-harmonic frequency is observed at 233 GHz for 1.45-μm channel length. This structure provides feasibility of generating a tunable millimeter wave or terahertz wave source and has an overwhelming advantage over equivalent traditional vertical structure because of increased facilitated integration and flexibility. (orig.)

  13. 52-GHz Millimetre-Wave PLL Synthesizer

    OpenAIRE

    Lee, Ja-Yol; Yu, Hyun-Kyu

    2010-01-01

    In this chapter, we design and fabricate a 52GHz frequency synthesizer for 60GHz dualconversion receiver using SiGe BiCMOS process technology. The designed PLL-based frequency synthesizer consists of a 26-GHz PLL and a 52-GHz frequency doubler. In the

  14. Design of Subharmonic Mixers above 100 GHz

    Institute of Scientific and Technical Information of China (English)

    Bo Zhang; Ge Liu; Zhe Chen; ; Xiao-Fan Yang; Ning-Bo Chen; San-Tong Wu; Yong Fan

    2013-01-01

    This paper presents the design and simulation of several fixed-tuned sub-harmonic mixers cover frequencies from 110 GH to 130 GHz, 215 GH to 235 GHz, 310 GH to 350 GHz, and 400 GH to 440 GHz. Among them, 120 GHz, 225 GHz, 330 GHz subharmonic mixers are designed with flip-chipped planar schottky diode mounted onto a suspended quartz-based substrate, the 225 GHz and 425 GHz subharmonic mixers are GaAs membrane integrated, and the 115 GHz subharmonic mixer has been fabricated and tested already.

  15. GMRT Observations of the 2006 outburst of the Nova RS Ophiuchi: First detection of emission at radio frequencies < 1.4 GHz

    CERN Document Server

    Kantharia, N G; Prabhu, T P; Ramya, S; Bode, M F; Eyres, S P S; O'Brien, T J

    2007-01-01

    The first low radio frequency (<1.4 GHz) detection of the outburst of the recurrent nova RS Ophiuchi is presented in this letter. Radio emission was detected at 0.61 GHz on day 20 with a flux density of ~48 mJy and at 0.325 GHz on day 38 with a flux density of ~ 44 mJy. This is in contrast with the 1985 outburst when it was not detected at 0.327 GHz even on day 66. The emission at low radio frequencies is clearly non-thermal and is well-explained by a synchrotron spectrum of index alpha ~ -0.8 (S propto nu^alpha) suffering foreground absorption due to the pre-existing, ionized, warm, clumpy red giant wind. The absence of low frequency radio emission in 1985 and the earlier turn-on of the radio flux in the current outburst are interpreted as being due to higher foreground absorption in 1985 compared to that in 2006, suggesting that the overlying wind densities in 2006 are only ~30% of those in 1985.

  16. Dielectric Properties and Oxidation Roasting of Molybdenite Concentrate by Using Microwave Energy at 2.45 GHz Frequency

    Science.gov (United States)

    Yonglin, Jiang; Bingguo, Liu; Peng, Liu; Jinhui, Peng; Libo, Zhang

    2017-09-01

    Conversion of electromagnetic energy into heat depends largely on the dielectric properties of the material being treated. Therefore, determining the dielectric properties of molybdenite concentrate and its microwave power penetration depth in relation to a temperature increment at the commercial frequency of 2.45 GHz is necessary to design industrial microwave processing units. In this study, the dielectric constants increased as the temperature increased in the entire experimental range. The loss factor presented an opposite trend, except for 298 K to 373 K (25 °C to 100 °C) in which a cavity perturbation resonator was used. The plots of nonlinear surface fitting indicate that the increase in dielectric loss causes a considerable decrease in penetration depth, but the dielectric constants exert a small positive effect. The thermogravimetric analysis (TGA-DSC) of the molybdenite concentrate was carried out to track its thermal decomposition process, aim to a dielectric analysis during the microwave heating. MoO3 was prepared from molybdenite concentrate through oxidation roasting in a microwave heating system and a resistance furnace, respectively. The phase transitions and morphology evolutions during oxidation roasting were characterized through X-ray diffraction and scanning electron microscopy. Results show that microwave thermal technique can produce high-purity molybdenum trioxide.

  17. Injection-locking of two frequency-doubled lasers with 3.2 GHz offset for driving Raman transitions with low photon scattering in $^{43}$Ca$^+$

    CERN Document Server

    Linke, N M; Lucas, D M

    2013-01-01

    We describe the injection locking of two infrared (794 nm) laser diodes which are each part of a frequency doubled laser system. An acousto-optic modulator (AOM) in the injection path gives an offset of 1.6 GHz between the lasers for driving Raman transitions between states in the hyperfine split (by 3.2 GHz) ground level of $^{43}$Ca$^+$. The offset can be disabled for use in $^{40}$Ca$^+$. We measure the relative linewidth of the frequency-doubled beams to be 42 mHz in an optical heterodyne measurement. The use of both injection locking and frequency doubling combines spectral purity with high optical power. Our scheme is applicable for providing Raman beams across other ion species and neutral atoms where coherent optical manipulation is required.

  18. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences

    CERN Document Server

    Biri, S; Muramatsu, M; Drentje, A G; Rácz, R; Yano, K; Kato, Y; Sasaki, N; Takasugi, W

    2015-01-01

    The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide bandwidth (17.1-18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1-18.5 GHz), and the effec...

  19. Studying integrated silicon-lens antennas for radio communication systems operated in the 60 GHz frequency band

    Science.gov (United States)

    Artemenko, A. A.; Mal'tsev, A. A.; Maslennikov, R. O.; Sevastyanov, A. G.; Ssorin, V. N.

    2013-01-01

    We consider the development of an integrated lens antenna for LAN radio communication systems operated in the 60 GHz frequency band. The antenna is an extended hemispherical silicon lens. On its flat surface, a microstrip antenna element is located. The use of silicon, which has a dielectric permittivity ɛ = 11.7, as the lens material ensures the maximum range of scanning angles for the minimum axial size of the lens. The approximate analytical formulas, which are used for initial calculations of the lens parameters, allow one to evaluate the basic parameters of the lens antenna integrated with the microstrip antenna element. For further optimizing the parameters of the lens and the antenna element, 3D simulation of the electromagnetic-field distribution was performed. Based on its results, we have developed and manufactured extended hemispherical silicon lenses, which had radii of 6 and 12 mm. The planar microstrip antenna element was manufactured by the low temperature co-fired ceramics (LTCC) technology. The results of simulation and experimental studies of the manufactured prototypes demonstrate that the developed lens antennas has directivities of 17.6 and 23.1 dBi for lenses with radii of 6 and 12 mm, respectively. In this case, the maximum beam deflection angle is achieved, which is equal to 55°, while the permissible decrease in the directivity is no more than 6 dBi compared with the case of a non-deflected beam. The obtained results show that the developed integrated lens antennas can find applications in high-speed radio communication systems operated in the millimeter-wave range.

  20. Site Evaluation and RFI spectrum measurements in Portugal at the frequency range 0.408-10 GHz for a GEM polarized galactic radio emission experiment

    CERN Document Server

    Fonseca, R; Cupido, L; dos Santos, D M; Smoot, G F; Tello, C A S

    2004-01-01

    We probed for Radio Frequency Interference (RFI) for the three potential Galactic Emission Mapping Experiment (GEM) sites at Portugal using custom made omnidirectional disconic antennas. For the installation of a 10-meter dish dedicated to the mapping of Polarized Galactic Emission foreground planned for 2005-2007 in the 5-10 GHz band, the three sites chosen as suitable to host the antenna were surveyed for local radio pollution in the frequency range [0.01-10] GHz. Tests were done to look for radio broadcasting and mobile phone emission lines in the radio spectrum. The results show one of the sites to be almost entirely RFI clean and showing good conditions to host the experiment.

  1. Planck intermediate results. VII. Statistical properties of infrared and radio extragalactic sources from the Planck Early Release Compact Source Catalogue at frequencies between 100 and 857 GHz

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Argüeso, F.; Arnaud, M.; Ashdown, M.; Atrio-Barandela, F.; Aumont, J.; Baccigalupi, C.; Balbi, A.; Banday, A. J.; Barreiro, R. B.; Battaner, E.; Benabed, K.; Benoît, A.; Bernard, J.-P.; Bersanelli, M.; Bethermin, M.; Bhatia, R.; Bonaldi, A.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Burigana, C.; Cabella, P.; Cardoso, J.-F.; Catalano, A.; Cayón, L.; Chamballu, A.; Chary, R.-R.; Chen, X.; Chiang, L.-Y.; Christensen, P. R.; Clements, D. L.; Colafrancesco, S.; Colombi, S.; Colombo, L. P. L.; Coulais, A.; Crill, B. P.; Cuttaia, F.; Danese, L.; Davis, R. J.; de Bernardis, P.; de Gasperis, G.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Dörl, U.; Douspis, M.; Dupac, X.; Efstathiou, G.; Enßlin, T. A.; Eriksen, H. K.; Finelli, F.; Forni, O.; Fosalba, P.; Frailis, M.; Franceschi, E.; Galeotta, S.; Ganga, K.; Giard, M.; Giardino, G.; Giraud-Héraud, Y.; González-Nuevo, J.; Górski, K. M.; Gregorio, A.; Gruppuso, A.; Hansen, F. K.; Harrison, D.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Jaffe, T. R.; Jaffe, A. H.; Jagemann, T.; Jones, W. C.; Juvela, M.; Keihänen, E.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Knox, L.; Kunz, M.; Kurinsky, N.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lawrence, C. R.; Leonardi, R.; Lilje, P. B.; López-Caniego, M.; Macías-Pérez, J. F.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martínez-González, E.; Masi, S.; Massardi, M.; Matarrese, S.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Mitra, S.; Miville-Deschènes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Osborne, S.; Pajot, F.; Paladini, R.; Paoletti, D.; Partridge, B.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Poutanen, T.; Pratt, G. W.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Renault, C.; Ricciardi, S.; Riller, T.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sajina, A.; Sandri, M.; Savini, G.; Scott, D.; Smoot, G. F.; Starck, J.-L.; Sudiwala, R.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Türler, M.; Valenziano, L.; Van Tent, B.; Vielva, P.; Villa, F.; Vittorio, N.; Wade, L. A.; Wandelt, B. D.; White, M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2013-02-01

    We make use of the Planck all-sky survey to derive number counts and spectral indices of extragalactic sources - infrared and radio sources - from the Planck Early Release Compact Source Catalogue (ERCSC) at 100 to 857 GHz (3 mm to 350 μm). Three zones (deep, medium and shallow) of approximately homogeneous coverage are used to permit a clean and controlled correction for incompleteness, which was explicitly not done for the ERCSC, as it was aimed at providing lists of sources to be followed up. Our sample, prior to the 80% completeness cut, contains between 217 sources at 100 GHz and 1058 sources at 857 GHz over about 12 800 to 16 550 deg2 (31 to 40% of the sky). After the 80% completeness cut, between 122 and 452 and sources remain, with flux densities above 0.3 and 1.9 Jy at 100 and 857 GHz. The sample so defined can be used for statistical analysis. Using the multi-frequency coverage of the Planck High Frequency Instrument, all the sources have been classified as either dust-dominated (infrared galaxies) or synchrotron-dominated (radio galaxies) on the basis of their spectral energy distributions (SED). Our sample is thus complete, flux-limited and color-selected to differentiate between the two populations. We find an approximately equal number of synchrotron and dusty sources between 217 and 353 GHz; at 353 GHz or higher (or 217 GHz and lower) frequencies, the number is dominated by dusty (synchrotron) sources, as expected. For most of the sources, the spectral indices are also derived. We provide for the first time counts of bright sources from 353 to 857 GHz and the contributions from dusty and synchrotron sources at all HFI frequencies in the key spectral range where these spectra are crossing. The observed counts are in the Euclidean regime. The number counts are compared to previously published data (from earlier Planck results, Herschel, BLAST, SCUBA, LABOCA, SPT, and ACT) and models taking into account both radio or infrared galaxies, and covering a

  2. Time constants for temperature elevation in human models exposed to dipole antennas and beams in the frequency range from 1 to 30 GHz

    Science.gov (United States)

    Morimoto, Ryota; Hirata, Akimasa; Laakso, Ilkka; Ziskin, Marvin C.; Foster, Kenneth R.

    2017-03-01

    This study computes the time constants of the temperature elevations in human head and body models exposed to simulated radiation from dipole antennas, electromagnetic beams, and plane waves. The frequency range considered is from 1 to 30 GHz. The specific absorption rate distributions in the human models are first computed using the finite-difference time-domain method for the electromagnetics. The temperature elevation is then calculated by solving the bioheat transfer equation. The computational results show that the thermal time constants (defined as the time required to reach 63% of the steady state temperature elevation) decrease with the elevation in radiation frequency. For frequencies higher than 4 GHz, the computed thermal time constants are smaller than the averaging time prescribed in the ICNIRP guidelines, but larger than the averaging time in the IEEE standard. Significant differences between the different head models are observed at frequencies higher than 10 GHz, which is attributable to the heat diffusion from the power absorbed in the pinna. The time constants for beam exposures become large with the increase in beam diameter. The thermal time constant in the brain is larger than that in the superficial tissues at high frequencies, because the brain temperature elevation is caused by the heat conduction of energy absorbed in the superficial tissue. The thermal time constant is minimized with an ideal beam with a minimum investigated diameter of 10 mm this minimal time constant is approximately 30 s and is almost independent of the radiation frequency, which is supported by analytic methods. In addition, the relation between the time constant, as defined in this paper, and ‘averaging time’ as it appears in the exposure limits is discussed, especially for short intense pulses. Similar to the laser guidelines, provisions should be included in the limits to limit the fluence for such pulses.

  3. Digital Predistortion of 75-110GHzW-Band Frequency Multiplier for Fiber Wireless Short Range Access Systems

    DEFF Research Database (Denmark)

    Zhao, Ying; Pang, Xiaodan; Deng, Lei

    2011-01-01

    We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated.......We present a digital predistortion technique to effectively compensate high nonlinearity of a sextuple multiplier operating at 99.6GHz. An 18.9dB adjacent-channel power ratio (ACPR) improvement is guaranteed and a W-band fiber-wireless system is experimentally investigated....

  4. Modulation of electromagnetic and absorption properties in 18-26.5 GHz frequency range of strontium hexaferrites with doping of cobalt-zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Pubby, Kunal; Narang, Sukhleen Bindra [Guru Nanak Dev University, Department of Electronics Technology, Amritsar (India); Kaur, Prabhjyot; Chawla, S.K. [Guru Nanak Dev University, Department of Chemistry, Centre for Advanced Studies-I, Amritsar (India)

    2017-05-15

    Hexaferrite nano-particles of stoichiometric composition Sr(CoZr){sub x}Fe{sub 12-2x}O{sub 19}, with x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0 were prepared using sol-gel auto-combustion route owing to its advantages such as low sintering temperature requirement, homogeneity and uniformity of grains. Tartaric acid as a fuel was utilized to complete the chemical reaction. The goal of this study is to analyse the effect of co-substitution of cobalt and zirconium on the electromagnetic and absorption properties of pure SrFe{sub 12}O{sub 19} hexaferrite. The properties were measured on the rectangular pellets of thickness 2.5 mm for K-frequency band using Vector Network Analyzer. The doping of Co-Zr has resulted in increase in real as well as imaginary parts of permittivity. The values of real permittivity lie in the range 3.6-7.0 for all the composition. The real part of permeability remains in range 0.7-1.6 in the studied frequency band for all the samples and shows slightly increasing trend with frequency. The maximum values of dielectric loss tangent peak (3.04) and magnetic loss tangent peak (2.34), among all the prepared compositions, have been observed for composition x = 0.2. Compositions with x = 0.6 and x = 0.0 also have high dielectric and magnetic loss peaks. Dielectric loss peaks are attributed to dielectric resonance and magnetic loss peaks are attributed to natural resonance. Experimentally determined reflection loss results show that all six compositions of prepared series have high values of absorption to propose them as single-layer absorbers in 18-26.5 GHz frequency range. The composition with x = 0.2 has maximum absorption capacity with reflection loss peak of -37.2 dB at 24.3 GHz frequency. The undoped composition also has high absorption peak (-25.46 dB), but -10 dB absorption bandwidth is minimum (2.2 GHz) out of the present series. Maximum absorption bandwidth is obtained for x = 1.0 (4.1 GHz). Other doped compositions also have high absorption bandwidth

  5. Effect of frequency tuning on bremsstrahlung spectra, beam intensity, and shape in the 10 GHz NANOGAN electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, G., E-mail: gerosro@gmail.com; Mal, Kedar; Kumar, Narender; Lakshmy, P. S.; Mathur, Y.; Kumar, P.; Kanjilal, D.; Roy, A. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi (India); Baskaran, R. [Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamilnadu (India)

    2014-02-15

    Studies on the effect of the frequency tuning on the bremsstrahlung spectra, beam intensities, and beam shape of various ions have been carried out in the 10 GHz NANOGAN ECR ion source. The warm and cold components of the electrons were found to be directly correlated with beam intensity enhancement in case of Ar{sup 9+} but not so for O{sup 5+}. The warm electron component was, however, much smaller compared to the cold component. The effect of the fine tuning of the frequency on the bremsstrahlung spectrum, beam intensities and beam shape is presented.

  6. A 9.8-mW 1.2-GHz CMOS frequency synthesizer with a low phase-noise LC-VCO and an I/Q frequency divider

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhenrong; Zhuang Yiqi; Li Bing; Jin Gang, E-mail: allen_lzr@126.com [Key Laboratory of the Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices, School of Microelectronics, Xidian University, Xi' an 710071 (China)

    2011-07-15

    A 1.2 GHz frequency synthesizer integrated in a RF receiver for Beidou navigation is implemented in standard 0.18 {mu}m CMOS technology. A distributed biased varactor LC voltage-controlled oscillator is employed to achieve low tuning sensitivity and optimized phase noise performance. A high-speed and low-switching-noise divider-by-2 circuit based on a source-coupled logic structure is adopted to generate a quadrature (I/Q) local oscillating signal. A high-speed 8/9 dual-modulus prescaler (DMP), a programmable-delay phase frequency detector without dead-zone problem, and a programmable-current charge pump are also integrated into the frequency synthesizer. The frequency synthesizer demonstrates an output frequency from 1.05 to 1.30 GHz, and the phase noise is -98.53 dBc/Hz at 100-kHz offset and -121.92 dBc/Hz at 1-MHz offset from the carrier frequency of 1.21 GHz. The power dissipation of the core circuits without the output buffer is 9.8 mW from a 1.8 V power supply. The total area of the receiver is 2.4 x 1.6 mm{sup 2}. (semiconductor integrated circuits)

  7. 1 Gbps full-duplex links for ultra-dense-WDM 6.25 GHz frequency slots in optical metro-access networks.

    Science.gov (United States)

    Altabas, Jose A; Izquierdo, David; Lazaro, Jose A; Lerin, Adolfo; Sotelo, Felix; Garces, Ignacio

    2016-01-11

    1 Gbps full-duplex optical links for 6.25 GHz ultra dense WDM frequency slots are demonstrated and optimized for cost-effective metro-access networks. The OLT-ONU downlinks are based on 1 Gbps Nyquist-DPSK using MZM and single-detector heterodyne reception obtaining a sensitivity of -52 dBm. The ONU-OLT uplinks are based on 1 Gbps NRZ-DPSK by directly phase modulated DFB and also single-detector heterodyne reception obtaining same sensitivity of -52 dBm. The power budget of full-duplex link is 43 dB. These proposed links can provide service to 16 (32) users at each 100 (200) GHz WDM channel.

  8. On the determination of the dynamic properties of a transformer oil based ferrofluid in the frequency range 0.1-20 GHz

    Science.gov (United States)

    Fannin, P. C.; Vekas, L.; Marin, C. N.; Malaescu, I.

    2017-02-01

    Complex susceptibility measurements provide a unique and efficient means for the investigation and determination of the dynamic properties of magnetic fluids. In particular, measurement of the frequency, f(Hz), and field, H(kA/m), dependent, complex susceptibility, χ(ω, Η)= χ‧(ω, Η)-iχ″(ω, Η), of magnetic fluids has proven to be a valuable and reliable technique for investigating such properties. The experimental data presented here was obtained from measurements of a transformer oil based ferrofluid, with measurements being performed over the frequency range 0.1-20 GHz and polarising fields 0-168 kA/m. In the case of transformer oil magnetic fluids, the normal measurement emphasis has been on the investigation of their dielectric properties, including the effects which lightning may have on these properties. Little has been reported on the measurement of the corresponding magnetic susceptibility, χ(ω), of such fluids and in this paper we address this fact. Thus we consider it worthwhile, in the case of a transformer with magnetic fluid transformer oil, being affected as a result of a lightening occurrence, to have knowledge of the fluids dynamic properties, at the microwave frequencies. In the process of determining the sample susceptibility profiles, it was found that the peak value of the χ″(ω) component, was approximately constant over the frequency range 2.4-6.3 GHz. From this it was determined that the fluid was effectively operating as a wideband absorber over a bandwidth of 3.9 GHz.

  9. Phase-noise characteristics of a 25-GHz-spaced optical frequency comb based on a phase- and intensity-modulated laser.

    Science.gov (United States)

    Ishizawa, Atsushi; Nishikawa, Tadashi; Mizutori, Akira; Takara, Hidehiko; Takada, Atsushi; Sogawa, Tetsuomi; Koga, Masafumi

    2013-12-02

    We investigated phase-noise characteristics of both a phase/intensity-modulated laser with 25-GHz mode spacing and a mode-locked fiber laser with carrier-envelope-offset (CEO) locking. As the separation from the frequency of the continuous wave (CW) laser diode (LD) for a seed light source increases, the integrated phase noise of each comb mode of both the phase/intensity-modulated laser and supercontinuum light originating from it increases with the same slope as a function of mode number. The dependence of the integrated phase noise on mode number with the phase/intensity-modulated laser is much larger than with the mode-locked fiber laser of the CEO locking. However, the phase noise of the phase/intensity-modulated laser is extremely lower than that of the mode-locked fiber laser with CEO locking in the frequency region around the CW LD. The phase noise of the phase/intensity-modulated laser with 25-GHz mode spacing and that of the mode-locked fiber laser with the CEO locking could be estimated and were found to be almost the same at the wavelengths required in an f-to-2f self-referencing interferometer. Our experimental results indicate the possibility of achieving an offset-frequency-locked frequency comb with the phase/intensity-modulated laser.

  10. Frequency response and bandwidth enhancement in Ge/Si avalanche photodiodes with over 840 GHz gain-bandwidth-product.

    Science.gov (United States)

    Zaoui, Wissem Sfar; Chen, Hui-Wen; Bowers, John E; Kang, Yimin; Morse, Mike; Paniccia, Mario J; Pauchard, Alexandre; Campbell, Joe C

    2009-07-20

    In this work we report a separate-absorption-charge-multiplication Ge/Si avalanche photodiode with an enhanced gain-bandwidth-product of 845 GHz at a wavelength of 1310 nm. The corresponding gain value is 65 and the electrical bandwidth is 13 GHz at an optical input power of -30 dBm. The unconventional high gain-bandwidth-product is investigated using device physical simulation and optical pulse response measurement. The analysis of the electric field distribution, electron and hole concentration and drift velocities in the device shows that the enhanced gain-bandwidth-product at high bias voltages is due to a decrease of the transit time and avalanche build-up time limitation at high fields.

  11. Survey of the sky at the 8. 7 and 14. 4 GHz frequencies in the 0 deg - 4 deg declination range

    Energy Technology Data Exchange (ETDEWEB)

    Amirkhanyan, V.R.; Gorshkov, A.G.; Kapustkin, A.A.; Konnikova, V.K.; Lazutkin, A.N.; Larionov, M.G.; Nikanorov, A.S.; Sidorenkov, V.N.; Ugol' kova, L.S.; Khromov, O.I. (Moskovskij Gosudarstvennyj Univ. (USSR). Gosudarstvennyj Astronomicheskij Inst. ' ' GAISh' ' )

    Using the RATAN-600 radiotelescope of the USSR Academy of Sciences (from March 1979 to January 1980) the sky is observed at the 8.7 and 14.4 GHz frequencies in the 0-4 deg declination range. Lists of 82 and 24 radiosources detected at the given frequencies are presented. Six radiosources are detected for the first time. Right ascension and declination, as well as the maximum values of radio-frequency radiation fluxes are given. The problems of measuring accuracies of fluxes and coordinates and the problem of validity of detected radiosources are discussed. On the basis of comparison of the data obtained with those in other works the systematic deviation in fluxes of sources is not more than 7%.

  12. Photonic filtering of microwave signals in the frequency range of 0.01-20 GHz using a Fabry-Perot filter

    Energy Technology Data Exchange (ETDEWEB)

    Aguayo-Rodriguez, G; Zaldivar-Huerta, I E [Instituto Nacional de Astrofisica, Optica y Electronica (INAOE). Sta. Maria Tonantzintla, Pue. Mexico (Mexico); GarcIa-Juarez, A [Depto. de Investigacion en Fisica, Universidad de Sonora (UNISON) Hermosillo, Son. Mexico (Mexico); Rodriguez-Asomoza, J [Depto. de Ingenieria Electronica, Universidad de las Americas-Puebla (UDLA). San Andres Cholula, Pue. Mexico (Mexico); Larger, L; Courjal, N [Laboratoire d' Optique P. M. Duffieux, UMR 6603 CNRS, Institut des Microtechiques de Franche-Comte, FRW 0067, UFR Sciences et Techniques, Universite de Franche-Comte (UFC), Besancon cedex (France)

    2011-01-01

    We demonstrate experimentally the efficiency of tuning of a photonic filter in the frequency range of 0.01 to 20 GHz. The presented work combines the use of a multimode optical source associated with a dispersive optical fiber to obtain the filtering effect. Tunability effect is achieved by the use of a Fabry-Perot filter that allows altering the spectral characteristics of the optical source. Experimental results are validated by means of numerical simulations. The scheme here proposed has a potential application in the field of optical telecommunications.

  13. Astrometrically Registered Simultaneous Observations of the 22 GHz H$_2$O and the 43GHz SiO masers towards R Leonis Minoris using KVN and Source/Frequency Phase Referencing

    CERN Document Server

    Dodson, Richard; Jung, Tae-Hyun; Sohn, Bong-Won; Byun, Do-Young; Cho, Se-Hyung; Lee, Sang-Sung; Kim, Jongsoo; Kim, Kee-Tae; Oh, Chung-Sik; Han, Seog-Tae; Je, Do-Heung; Chung, Moon-Hee; Wi, Seog-Oh; Kang, Jiman; Lee, Jung-Won; Chung, Hyunsoo; Kim, Hyo-Ryoung; Kim, Hyun-Goo; Lee, Chang-Hoon; Roh, Duk-Gyoo; Oh, Se-Jin; Yeom, Jae-Hwan; Song, Min-Gyu; Kang, Yong-Woo

    2014-01-01

    Oxygen-rich Asymptotic Giant Branch (AGB) stars can be intense emitters of SiO ($v$=1 and 2, J=1$\\rightarrow$0) and H$_2$O maser lines at 43 and 22 GHz, respectively. VLBI observations of the maser emission provide a unique tool to probe the innermost layers of the circumstellar envelopes in AGB stars. Nevertheless, the difficulties in achieving astrometrically aligned \\water\\ and $v$=1 and $v$=2 SiO maser maps have traditionally limited the physical constraints that can be placed on the SiO maser pumping mechanism. We present phase referenced simultaneous spectral-line VLBI images for the SiO $v$=1 and $v$=2, J=1$\\rightarrow$0, and H$_2$O maser emission around the AGB star R\\,LMi, obtained from the Korean VLBI Network (KVN). The simultaneous multi-channel receivers of the KVN offer great possibilities for astrometry in the frequency domain. With this facility we have produced images with bona-fide absolute astrometric registration between high frequency maser transitions of different species to provide the p...

  14. Automated Microwave Complex on the Basis of a Continuous-Wave Gyrotron with an Operating Frequency of 263 GHz and an Output Power of 1 kW

    Science.gov (United States)

    Glyavin, M. Yu.; Morozkin, M. V.; Tsvetkov, A. I.; Lubyako, L. V.; Golubiatnikov, G. Yu.; Kuftin, A. N.; Zapevalov, V. E.; V. Kholoptsev, V.; Eremeev, A. G.; Sedov, A. S.; Malygin, V. I.; Chirkov, A. V.; Fokin, A. P.; Sokolov, E. V.; Denisov, G. G.

    2016-02-01

    We study experimentally the automated microwave complex for microwave spectroscopy and diagnostics of various media, which was developed at the Institute of Applied Physics of the Russian Academy of Sciences in cooperation with GYCOM Ltd. on the basis of a gyrotron with a frequency of 263 GHz and operated at the first gyrofrequency harmonic. In the process of the experiments, a controllable output power of 0 .1 -1 kW was achieved with an efficiency of up to 17 % in the continuous-wave generation regime. The measured radiation spectrum with a relative width of about 10 -6 and the frequency values measured at various parameters of the device are presented. The results of measuring the parameters of the wave beam, which was formed by a built-in quasioptical converter, as well as the data obtained by measuring the heat loss in the cavity and the vacuum output window are analyzed.

  15. Noise and Spurious Tones Management Techniques for Multi-GHz RF-CMOS Frequency Synthesizers Operating in Large Mixed Analog-Digital SOCs

    Directory of Open Access Journals (Sweden)

    Maxim Adrian

    2006-01-01

    Full Text Available This paper presents circuit techniques and power supply partitioning, filtering, and regulation methods aimed at reducing the phase noise and spurious tones in frequency synthesizers operating in large mixed analog-digital system-on-chip (SOC. The different noise and spur coupling mechanisms are presented together with solutions to minimize their impact on the overall PLL phase noise performance. Challenges specific to deep-submicron CMOS integration of multi-GHz PLLs are revealed, while new architectures that address these issues are presented. Layout techniques that help reducing the parasitic noise and spur coupling between digital and analog blocks are described. Combining system-level and circuit-level low noise design methods, low phase noise frequency synthesizers were achieved which are compatible with the demanding nowadays wireless communication standards.

  16. Patterned FeNi soft magnetic strips film with tunable resonance frequency from 1 to 10.6 GHz

    Science.gov (United States)

    Ren, Yong; Li, Xinxi; Wang, Yan; Ren, Jiankun; Zhang, Yan; Dai, Bo; Yan, Haiyang; Sun, Guangai; Peng, Shuming

    2016-08-01

    Soft magnetic films with a wide-range tunable ferromagnetic resonance frequency are suitable for miniaturization and multifunctionalization of microwave integrated circuits. Fabrication of these films for high-frequency applications is usually complicated and difficult. We demonstrate a simple method to fabricate patterned FeNi soft magnetic strip films by magnetron sputtering and photolithography. Films prepared by this method exhibits a tunable in-plane uniaxial magnetic anisotropy (IPUMA) for different strip widths and gaps. As the strip widths changing from 500 to 2 μm, the IPUMA field increases monotonically from 2.2 to 576 Oe and resonance frequency from 1 to 10.6 GHz(which covers four microwave bands, including the L,S,C and X bands) respectively. This ultra-wide-range adjustability of resonance frequency can be attributed to shape anisotropy of strips. Considering that FeNi alloy has relatively low magnetocrystalline anisotropy, so a wider adjustable range of resonance frequency could be obtained using materials with stronger magnetocrystalline anisotropy.

  17. Chip design of a 5.8-GHz fractional-N frequency synthesizer with a tunable Gm-C loop filter

    Institute of Scientific and Technical Information of China (English)

    Huang Jhin-Fang; Liu Ron-Yi; Lai Wen-Cheng; Shin Chun-Wei; Hsu Chien-Ming

    2012-01-01

    This paper proposes a novel Gm-C loop filter insteai of a conventional passive loop filter used in a phase-locked loop.The innovative advantage of the proposed architecture is tunable loop filter bandwidth and hence the process variations of passive elements of resistance R and capacitance C can be overcome and the chip area is greatly reduced.Furthermore,the MASH 1-1-1 sigma-delta (Σ△) modulator is adopted for performing the fractional division number and hence improves the phase noise as well.Measured results show that the locked phase noise is -114.1 dBc/Hz with lower Gm-C bandwidth and -111.7 dBm/C with higher Gm-C bandwidth at 1 MHz offset from carrier of 5.68 GHz.Including pads and built-in Gm-C filter,the chip area of the proposed frequency synthesizer is 1.06 mm2.The output power is -8.69 dBm at 5.68 GHz and consumes 56 mW with an off-chip buffer from 1.8-V supply voltage.

  18. GHz magnetic film inductors

    CERN Document Server

    Korenivski, V

    2000-01-01

    Use of magnetic films for miniaturization of planar inductors operating at ultra-high frequencies is reviewed. Materials and design aspects determining the efficiency of the devices are analyzed. Mechanisms involved in magnetic dissipation and their role in limiting the device operation frequency range and quality factor are discussed. Typical inductor geometries are considered. A magnetically sandwiched strip inductor is argued to hold a promise for GHz applications.

  19. Dosimetry of a set-up for the exposure of newborn mice to 2.45-GHZ WiFi frequencies.

    Science.gov (United States)

    Pinto, R; Lopresto, V; Galloni, P; Marino, C; Mancini, S; Lodato, R; Pioli, C; Lovisolo, G A

    2010-08-01

    This work describes the dosimetry of a two waveguide cell system designed to expose newborn mice to electromagnetic fields associated with wireless fidelity signals in the frequency band of 2.45 GHz. The dosimetric characterisation of the exposure system was performed both numerically and experimentally. Specific measures were adopted with regard to the increase in both weight and size of the biological target during the exposure period. The specific absorption rate (SAR, W kg(-1)) for 1 W of input power vs. weight curve was assessed. The curve evidenced an SAR pattern varying from 6 W kg(-1) during the first 5 weeks of the life of mice, with a peak resonance phenomenon at a weight around 5 g. This curve was used to set the appropriate level of input power during experimental sessions to expose the growing mice to a defined and constant dose.

  20. Improving single slope ADC and an example implemented in FPGA with 16.7 GHz equivalent counter clook frequency

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jinyuan; /Fermilab; Odeghe, John; /South Carolina State U.; Stackley, Scott; /Boston U.; Zha, Charles; /Rice U.

    2011-11-01

    Single slope ADC is a common building block in many ASCI or FPGA based front-end systems due to its simplicity, small silicon footprint, low noise interference and low power consumption. In single slope ADC, using a Gray code counter is a popular scheme for time digitization, in which the comparator output drives the clock (CK) port of a register to latch the bits from the Gray code counter. Unfortunately, feeding the comparator output into the CK-port causes unnecessary complexities and artificial challenges. In this case, the propagation delays of all bits from the counter to the register inputs must be matched and the counter must be a Gray code one. A simple improvement on the circuit topology, i.e., feeding the comparator output into the D-port of a register, will avoid these unnecessary challenges, eliminating the requirement of the propagation delay match of the counter bits and allowing the use of regular binary counters. This scheme not only simplifies current designs for low speeds and resolutions, but also opens possibilities for applications requiring higher speeds and resolutions. A multi-channel single slope ADC based on a low-cost FPGA device has been implemented and tested. The timing measurement bin width in this work is 60 ps, which would need a 16.7 GHz counter clock had it implemented with the conventional Gray code counter scheme. A 12-bit performance is achieved using a fully differential circuit making comparison between the input and the ramping reference, both in differential format.

  1. Interaction of electromagnetic radiation in the 20-200 GHz frequency range with arrays of carbon nanotubes with ferromagnetic nanoparticles.

    Science.gov (United States)

    Atdayev, Agylych; Danilyuk, Alexander L; Prischepa, Serghej L

    2015-01-01

    The interaction of electromagnetic radiation with a magnetic nanocomposite based on carbon nanotubes (CNT) is considered within the model of distributed random nanoparticles with a core-shell morphology. The approach is based on a system composed of a CNT conducting resistive matrix, ferromagnetic inductive nanoparticles and the capacitive interface between the CNT matrix and the nanoparticles, which form resonance resistive-inductive-capacitive circuits. It is shown that the influence of the resonant circuits leads to the emergence of specific resonances, namely peaks and valleys in the frequency dependence of the permeability of the nanocomposite, and in the frequency dependence of the reflection and transmission of electromagnetic radiation.

  2. Interaction of electromagnetic radiation in the 20–200 GHz frequency range with arrays of carbon nanotubes with ferromagnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Agylych Atdayev

    2015-04-01

    Full Text Available The interaction of electromagnetic radiation with a magnetic nanocomposite based on carbon nanotubes (CNT is considered within the model of distributed random nanoparticles with a core–shell morphology. The approach is based on a system composed of a CNT conducting resistive matrix, ferromagnetic inductive nanoparticles and the capacitive interface between the CNT matrix and the nanoparticles, which form resonance resistive–inductive–capacitive circuits. It is shown that the influence of the resonant circuits leads to the emergence of specific resonances, namely peaks and valleys in the frequency dependence of the permeability of the nanocomposite, and in the frequency dependence of the reflection and transmission of electromagnetic radiation.

  3. Tunable Twin Matching Frequency (fm1/fm2) Behavior of Ni1‑xZnxFe2O4/NBR Composites over 2–12.4 GHz: A Strategic Material System for Stealth Applications

    Science.gov (United States)

    Saini, Lokesh; Patra, Manoj Kumar; Jani, Raj Kumar; Gupta, Goutam Kumar; Dixit, Ambesh; Vadera, Sampat Raj

    2017-03-01

    The gel to carbonate precipitate route has been used for the synthesis of Ni1‑xZnxFe2O4 (x = 0, 0.25, 0.5 and 0.75) bulk inverse spinel ferrite powder samples. The optimal zinc (50%) substitution has shown the maximum saturation magnetic moment and resulted into the maximum magnetic loss tangent (tanδm) > ‑1.2 over the entire 2–10 GHz frequency range with an optimum value ~‑1.75 at 6 GHz. Ni0.5Zn0.5Fe2O4- Acrylo-Nitrile Butadiene Rubber (NBR) composite samples are prepared at different weight percentage (wt%) of ferrite loading fractions in rubber for microwave absorption evaluation. The 80 wt% loaded Ni0.5Zn0.5Fe2O4/NBR composite (FMAR80) sample has shown two reflection loss (RL) peaks at 5 and 10 GHz. Interestingly, a single peak at 10 GHz for 3.25 mm thickness, can be scaled down to 5 GHz by increasing the thickness up to 4.6 mm. The onset of such twin matching frequencies in FMAR80 composite sample is attributed to the spin resonance relaxation at ~5 GHz (fm1) and destructive interference at λm/4 matched thickness near ~10 GHz (fm2) in these composite systems. These studies suggest the potential of tuning the twin frequencies in Ni0.5Zn0.5Fe2O4/NBR composite samples for possible microwave absorption applications.

  4. A 2-to-2.4-GHz differentially-tuned fractional-N frequency synthesizer for DVB tuner applications

    Energy Technology Data Exchange (ETDEWEB)

    Meng Lingbu; Lu Lei; Zhao Wei; Tang Zhangwen, E-mail: zwtang@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2010-07-15

    This paper describes the design of a fractional-N frequency synthesizer for digital video broadcasting-terrestrial (DVB-T) receivers. Transfer functions in differentially-tuned PLL are derived and loop parameters are designed. In addition, a fully-differential charge pump is presented. An 8/9 high speed prescaler is analyzed and the design considerations for the CML logic are also presented. Test results show that the RMS phase error is less than 0.7{sup 0} in integer-N mode and less than 1{sup 0} in fractional-N mode. The implemented frequency synthesizer draws 10 mA from a 1.8-V supply while occupying a die area of about 1-mm{sup 2} in a 0.18-{mu}m CMOS process.

  5. A 2-to-2.4-GHz differentially-tuned fractional-N frequency synthesizer for DVB tuner applications

    Science.gov (United States)

    Lingbu, Meng; Lei, Lu; Wei, Zhao; Zhangwen, Tang

    2010-07-01

    This paper describes the design of a fractional-N frequency synthesizer for digital video broadcasting-terrestrial (DVB-T) receivers. Transfer functions in differentially-tuned PLL are derived and loop parameters are designed. In addition, a fully-differential charge pump is presented. An 8/9 high speed prescaler is analyzed and the design considerations for the CML logic are also presented. Test results show that the RMS phase error is less than 0.7° in integer-N mode and less than 1° in fractional-N mode. The implemented frequency synthesizer draws 10 mA from a 1.8-V supply while occupying a die area of about 1-mm2 in a 0.18-μm CMOS process.

  6. Research and Development of 2-frequency (110/138 GHz FADIS for JT-60SA ECHCD system

    Directory of Open Access Journals (Sweden)

    Idei H.

    2015-01-01

    Full Text Available A FAst DIrectional Switch (FADIS of 2-frequency (2-ƒ gyrotron system for the JT-60SA project is being developed under collaboration between Japan Atomic Energy Agency (JAEA and Kyushu University. At first, the frequency drift and dip in the gyrotron operation were measured to consider which kind of FADIS is preferred for application in the Electron Cyclotron Heating and Current Drive (ECHCD system for the JT- 60SA. Various types of the FADIS have been considered. A square corrugated waveguide diplexer system with double resonant rings was considered as one of the most attractive FADIS systems for stable high-power and long-pulse operations in the 2-ƒ JT-60SA ECHCD system.

  7. The contribution of microbunching instability to solar flare emission in the GHz to THz range of frequencies

    OpenAIRE

    Michael Klopf J.; Kaufmann P; Raulin J.-P.; Szpigel S.

    2014-01-01

    Recent solar flare observations in the sub-terahertz range have provided evidence of a new spectral component with fluxes increasing for larger frequencies, separated from the well-known microwave emission that maximizes in the gigahertz range. Suggested interpretations explain the terahertz spectral component but do not account for the simultaneous microwave component. We present a mechanism for producing the observed "double spectra." Based on coherent enhancement of synchrotron emission at...

  8. NMR GHZ

    CERN Document Server

    Laflamme, R; Zurek, W H; Catasti, P; Mariappan, S V S

    1998-01-01

    We describe the creation of a Greenberger-Horne-Zeilinger (GHZ) state of the form |000>+|111> (three maximally entangled quantum bits) using Nuclear Magnetic Resonance (NMR). We have successfully carried out the experiment using the proton and carbon spins of trichloroethylene, and confirmed the result using state tomography. We have thus extended the space of entangled quantum states explored systematically to three quantum bits, an essential step for quantum computation.

  9. Novel photoswitchable dielectric properties on nanomaterials of electronic core-shell γ-FeOx@Au@fullerosomes for GHz frequency applications

    Science.gov (United States)

    Wang, Min; Su, Chefu; Yu, Tzuyang; Tan, Loon-Seng; Hu, Bin; Urbas, Augustine; Chiang, Long Y.

    2016-03-01

    We unexpectedly observed a large amplification of the dielectric properties associated with the photoswitching effect and the new unusual phenomenon of delayed photoinduced capacitor-like (i.e. electric polarization) behavior at the interface on samples of three-layered core-shell (γ-FeOx@AuNP)@[C60(>DPAF-C9)]n2 nanoparticles (NPs) in frequencies of 0.5-4.0 GHz. The detected relative dielectric constant amplification was initiated upon switching off the light followed by relaxation to give an excellent recyclability. These NPs having e--polarizable fullerosomic structures located at the outer layer were fabricated from highly magnetic core-shell γ-FeOx@AuNPs. Surface-stabilized 2 in a core-shell structure was found to be capable of photoinducing the surface plasmonic resonance (SPR) effect by white LED light. The accumulated SPR energy was subsequently transferred to the partially bilayered C60(>DPAF-C9) fullerosomic membrane layer in a near-field (~1.5 nm) region without producing radiation heat. Since the monostatic SAR signal is dielectric property-dependent, we used these measurements to provide evidence of derived reflectivity changes on a surface coated with 2 at 0.5-4.0 GHz upon illumination of LED white light. We found that a high, >99%, efficiency of response amplification in image amplitude can be achieved.We unexpectedly observed a large amplification of the dielectric properties associated with the photoswitching effect and the new unusual phenomenon of delayed photoinduced capacitor-like (i.e. electric polarization) behavior at the interface on samples of three-layered core-shell (γ-FeOx@AuNP)@[C60(>DPAF-C9)]n2 nanoparticles (NPs) in frequencies of 0.5-4.0 GHz. The detected relative dielectric constant amplification was initiated upon switching off the light followed by relaxation to give an excellent recyclability. These NPs having e--polarizable fullerosomic structures located at the outer layer were fabricated from highly magnetic core-shell

  10. Analysing limits for human exposure to electromagnetic fields in accordance with ITU- k.52 standard for frequencies between 10 khz and 3 GHz in urban areas of Bucaramanga

    Directory of Open Access Journals (Sweden)

    José de Jesús Rugeles Uribe

    2010-04-01

    Full Text Available This article presents an overview of the results obtained from testing the limits of human exposure to 10KHz to 3GHZ frequencies in the city of Bucaramanga (Colombia, taking into account decree 195-2005 approved by the Colombian Ministry of Communications, based on International Telecommunication Union (ITU recommendation K.52. Measuring levels of exposure to electromagnetic radiation at three chosen locations in the city considered to be sensitive did not reveal that exposure limits were being exceeded. Mobile phone, modulated amplitude emission, frequency modulation and television bands installed at the sites several years ago were also measured. Levels ob-tained from electric field strength exceeded 100 dBuV / m in all cases, maximum value being 139 dBuV / m. Levels were well below exposure limits established by the K-52 rule. The highest levels for the general public’s exposure were 1.74964% in the AM band and 0.006408% for the cellular band between 869 and 894 MHz. This article also contains a description of the modules, exposure limits, acquisition and geo-positioning using the EspecVIEW tool designed for performing several types of measurements by Ministry officials and used in this study.

  11. A 3.1-4.8 GHz transmitter with a high frequency divider in 0.18 {mu}m CMOS for OFDM-UWB

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Renliang; Ren Junyan; Li Wei; Li Ning, E-mail: jyren@fudan.edu.c [Micro/Nano Science and Innovation Platform, State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)

    2009-12-15

    A fully integrated low power RF transmitter for a WiMedia 3.1-4.8 GHz multiband orthogonal frequency division multiplexing ultra-wideband system is presented. With a separate transconductance stage, the quadrature up-conversion modulator achieves high linearity with low supply voltage. The co-design of different resonant frequencies of the modulator and the differential to single (D2S) converter ensures in-band gain flatness. By means of a series inductor peaking technique, the D2S converter obtains 9 dB more gain without extra power consumption. A divided-by-2 divider is used for carrier signal generation. The measurement results show an output power between -10.7 and -3.1 dBm with 7.6 dB control range, an OIP3 up to 12 dBm, a sideband rejection of 35 dBc and a carrier rejection of 30 dBc. The ESD protected chip is fabricated in the Jazz 0.18 {mu}m RF CMOS process with an area of 1.74 mm{sup 2} and only consumes 32 mA current (at 1.8 V) including the test associated parts. (semiconductor integrated circuits)

  12. A novel high efficiency CMOS RF/DC power harvester based on constant on/off time buck controller for 60GHz frequency band

    Directory of Open Access Journals (Sweden)

    Ninić Marko

    2017-01-01

    Full Text Available A novel 60 GHz RF/DC power harvesting system is presented. The system consists of RF to DC rectifier and a DC/DC Buck converter based on constant ON/OFF time (COOT control. The rectifier has a structure of voltage doubler, but employs diodes that have lower parasitics compared to those of the standard MOSFET diodes, resulting in improved power conversion efficiency. The peak efficiency of the rectifier obtained with the extracted parasitics for the output power of 1 mW is about 25%. In order to keep the output voltage of the system to 1.2 V, the COOT control in the Buck converter is used. COOT control has much better efficiency at low output powers compared to the PWM systems. For correct operation of the COOT control, auxiliary sub-blocks: a low power high-speed comparator, a hysteresis comparator, and a high-speed voltage reference are designed and presented. The maximum switching frequency in the Buck converter is about 100MHz and the whole control system has very low static power consumption. The efficiency of the overall system for the output power of 1mW is about 21%. The system is designed in 65 nm CMOS technology.

  13. Compact MIMO Microstrip Antennas for USB Dongle Operating in 2.5–2.7 GHz Frequency Band

    Directory of Open Access Journals (Sweden)

    Vladimir Ssorin

    2012-01-01

    Full Text Available This paper considers design of microstrip MIMO antennas for an LTE/WiMAX USB dongle operating in the 2.5–2.7 GHz frequency band. The MIMO system includes two antenna elements with an additional requirement of high isolation between them that is especially difficult to realize due to size limitations of a USB dongle. Three approaches to achieve the needed system characteristics using microstrip PCB antennas are proposed. For the first design, high port-to-port isolation is achieved by using a decoupling techniques based on a direct connection of the antenna elements. For the second approach, high port-to-port isolation of the MIMO antenna system is realized by a lumped decorrelation capacitance between antenna elements feeding points. The third proposed antenna system does not use any special techniques, and high port-to-port isolation is achieved by using only the properties of a developed printed inverted-F antenna element. The designed MIMO antenna systems have the return loss S11 and the insertion loss S21 bandwidths of more than 200 MHz at the −8 dB level with the correlation coefficient lower than 0.1 and exhibit pattern diversity when different antenna elements are excited. Experimental measurements of the fabricated antenna systems proved the characteristics obtained from electromagnetic simulation.

  14. Electromagnetic shielding behavior of polyaniline using Red Mud (industrial waste) as filler in the X – band (8.2–12.4 GHz) frequency range

    Energy Technology Data Exchange (ETDEWEB)

    Pande, Anu; Gairola, Preeti [Uttaranchal University, Prem Nagar, Dehradun (India); Sambyal, Pradeep [National Physical Laboratory (CSIR), K, S. Krishnan Marg, New Delhi (India); Gairola, S.P., E-mail: spgairola10@gmail.com [Uttaranchal University, Prem Nagar, Dehradun (India); Kumar, Vinod [Centre for Energy Studies, Indian Institute of Technology, New Delhi (India); Singh, Kuldeep [Central Electrochemical Research Institute (CSIR), Karaikudi, Tamilnadu (India); Dhawan, S.K. [National Physical Laboratory (CSIR), K, S. Krishnan Marg, New Delhi (India)

    2017-03-01

    In today’s times where pollution of all kinds is at its peak, numerous efforts are being made to find proper waste disposal methods. Moving on the same lines, this paper presents an economical and environmentally safe method of disposal of red mud to control electromagnetic pollution by using it as an electromagnetic shielding material. Composites of PANI/RM have been prepared by in-situ chemical oxidative polymerization and have been tested for structural analysis, thermal stability and magnetization by XRD, TGA and VSM techniques respectively. Further, the composites have shown shielding effectiveness of 33–41 dB (>99.99% attenuation) in 8.2–12.4 GHz frequency range (X-band) at a thickness of 3 mm which is absorption dominated. Thus, the results conclude that the incorporation of red mud into polymer matrix can serve two purposes – firstly, it can provide a good alternative as a shielding material and secondly, it can prove to be a feasible way of waste disposal. - Highlights: • An attempt to find out application of red mud in controlling electromagnetic pollution. • Waste utilization for technology: Red mud is an insoluble industrial waste used for EMI Shielding application. • Using and testing of Red Mud as filler instead of the other widely used fillers. • Characterization of materials (Red Mud/Polyaniline composite) for EMI shielding Application. • EMI Shielding results discussions of new material (Red Mud/Polyaniline).

  15. Comparable effects of low-intensity electromagnetic irradiation at the frequency of 51.8 and 53 GHz and antibiotic ceftazidime on Lactobacillus acidophilus growth and survival.

    Science.gov (United States)

    Soghomonyan, Diana; Trchounian, Armen

    2013-01-01

    The effects of low-intensity electromagnetic irradiation (EMI) with the frequencies of 51.8 and 53 GHz on Lactobacillus acidophilus growth and survival were revealed. These effects were compared with antibacterial effects of antibiotic ceftazidime. Decrease in bacterial growth rate by EMI was comparable with the inhibitory effect of ceftazidime (minimal inhibitory concentration-16 μM) and no enhanced action was observed with combined effects of EMI and the antibiotic. However, EMI-enhanced antibiotic inhibitory effect on bacterial survival. The kinetics of the bacterial suspension oxidation-reduction potential up to 24 h of the growth was changed by EMI and ceftazidime. The changes were more strongly expressed by combined effects of EMI and antibiotic especially up to 12 h. Moreover, EMI did not change overall energy (glucose)-dependent H(+) efflux across the membrane but it increased N,N'-dicyclohexylcarbodiimide (DCCD)-inhibited H(+) efflux. In contrast, this EMI in combination with ceftazidime decreased DCCD-sensitive H(+) efflux. Low-intensity EMI had inhibitory effect on L. acidophilus bacterial growth and survival. The effect on bacterial survival was more significant in the combination with ceftazidime. The H(+)-translocating F 0 F 1-ATPase, for which DCCD is specific inhibitor, might be a target for EMI and ceftazidime. The revealed bactericide effects on L. acidophilus can be applied in biotechnology, food producing and safety technology.

  16. Wireless network of stand-alone end effect probes for soil in situ permittivity measurements over the 100MHZ-6GHz frequency range

    Science.gov (United States)

    Demontoux, François; Bircher, Simone; Ruffié, Gilles; Bonnaudiin, Fabrice; Wigneron, Jean-Pierre; Kerr, Yann

    2017-04-01

    Microwave remote sensing and non-destructive analysis are a powerful way to provide properties estimation of materials. Numerous applications using microwave frequency behavior of materials (remote sensing above land surfaces, non-destructive analysis…) are strongly dependent on the material's permittivity (i.e. dielectric properties). This permittivity depends on numerous parameters such as moisture, texture, temperature, frequency or bulk density. Permittivity measurements are generally carried out in the laboratory. Additionally, dielectric mixing models allow, over a restricted range of conditions, the assessment of a material's permittivity. in-situ measurements are more difficult to obtain. Some in situ measurement probes based on permittivity properties of soil exist (e.g. Time Domain Reflectometers and Transmissometers, capacitance and impedance sensors). They are dedicated to the acquisition of soil moisture data based on permittivity (mainly the real part) estimations over a range of frequencies from around 50 MHz to 1 or 2 GHz. Other Dielectric Assessment Kits exist but they are expensive and they are rather dedicated to laboratory measurements. Furthermore, the user can't address specific issues related to particular materials (e.g. organic soils) or specific measurement conditions (in situ long time records). At the IMS Laboratory we develop probes for in situ soil permittivity measurements (real and imaginary parts) in the 0.5 - 6 GHz frequency range. They are based on the end effect phenomenon of a coaxial waveguide and so are called end effect probes in this paper. The probes can be connected to a portable Vector Network Analyzer (VNA, ANRITSU MS2026A) for the S11 coefficient measurements needed to compute permittivity. It is connected to a PC to record data using an USB connection. This measurement set-up is already used for in situ measurement of soil properties in the framework of the European Space Agency's (ESA) SMOS space mission. However

  17. [Changes in ion transport through membranes, ATPase activity and antibiotics effects in Enterococcus hirae after low intensity electromagnetic irradiation of 51,8 and 53,0 GHz frequencies].

    Science.gov (United States)

    Torgomian, É; Oganian, V; Blbulian, C; Trchunian, A

    2013-01-01

    It was ascertained that one-hour exposure of Enterococcus hirae ATCC9790 bacteria grown under anaerobe condition during sugar (glucose) fermentation to coherent electromagnetic irradiation (EMI) of 51,8 and 53,0 GHz frequencies or millimeter waves (5,79 and 5,66 mm wavelengths) of low-intensity (flux capacity of 0,06 mW/sm2) caused a significant decrease in energy-dependent H+ and K+ transports across the membranes of whole cells. Therewith, K+ influx into cells was appreciably less at the frequency of 53,0 GHz. Likewise, a significant decrease of total and N,N'-dicyclohexylcarbodiimide-sensitive ATPase activity of the membrane vesicles occurred after EMI of 51,8 and 53,0 GHz. These results indicated the input of membranous changes in bacterial action of low intensity extremely high frequency EMI, when the F0F1-ATPase was probably playing a key role. Additionally, the enhancement of the effects of antibiotics--ceftriaxone, kanamycin and ampicillin at their minimal inhibitory concentrations (100, 200 and 1,4 microM, correspondingly) on the bacterial growth by these irradiations was shown. Also, combined action of EMI and antibiotics depressed strongly H+ and K+ fluxes across membrane. Especially, H+ flux was more sensitive to the action of ceftriaxone, but K+ flux was sensitive to kanamycin. All these made the assumption that EMI of 51,8 and 53,0 GHz frequencies, especially 53,0 GHz, was followed by change in bacterial sensitivity toward antibiotics that was more obvious with ceftriaxone and ampicillin.

  18. Performance Analysis of OFDM 60GHz System and SC-FDE 60GHz System

    Directory of Open Access Journals (Sweden)

    Han Xueyan

    2016-01-01

    Full Text Available In this paper, the performance of 60GHz wireless communication system with SC and OFDM is studied, the models of OFDM 60GHz system and SC 60GHz frequency domain equalization (SC-FDE system are established, and the bit error rate (BER performance of OFDM 60GHz system and SC-FDE 60GHz system in 802.15.3c channels is compared. The simulation results show that SC-FDE 60GHz system has a slight advantage over OFDM system in line-of-sight (LOS channels, while OFDM 60GHz system has a slight advantage over SC-FDE system in non-line-of-sight (NLOS channels. For 60GHz system, OFDM 60GHz system has a slight advantage over SC-FDE system in overcoming multipath fading, but the performance of both is close whether in the LOS or NLOS case.

  19. Fully Integrated 1.7GHz, 188dBc/Hz FoM, 0.8V, 320uW LC-tank VCO and Frequency Divider

    DEFF Research Database (Denmark)

    Midtgaard, Jesper Stolpe; Jeppesen, Thomas; Christensen, Kåre Tais;

    2005-01-01

    This paper presents a 0.13μm CMOS 1.7GHz VCO with frequency divider, suitable for ultra-low-power hearing-aid applications. The circuit has a 16% tuning range, a minimum power consumption of 320μW from a 0.8V power supply, power-supply and temperature compensation, an excellent 188dBc/Hz figure...

  20. Fiber-wireless transmission system of 108  Gb/sdata over 80 km fiber and 2×2multiple-input multiple-output wireless links at 100 GHz W-band frequency.

    Science.gov (United States)

    Li, Xinying; Dong, Ze; Yu, Jianjun; Chi, Nan; Shao, Yufeng; Chang, G K

    2012-12-15

    We experimentally demonstrate a seamlessly integrated fiber-wireless system that delivers a 108  Gb/s signal through 80 km fiber and 1 m wireless transport over free space at 100 GHz adopting polarization-division-multiplexing quadrature-phase-shift-keying (PDM-QPSK) modulation and heterodyning coherent detection. The X- and Y-polarization components of the optical PDM-QPSK baseband signal are simultaneously upconverted to 100 GHz wireless carrier by optical polarization-diversity heterodyne beating, and then independently transmitted and received by two pairs of transmitter and receiver antennas, which form a 2×2 multiple-input multiple-output wireless link. At the wireless receiver, two-stage downconversion is performed firstly in the analog domain based on balanced mixer and sinusoidal radio frequency signal, and then in the digital domain based on digital signal processing (DSP). Polarization demultiplexing is realized by the constant modulus algorithm in the DSP part at the receiver. The bit-error ratio for the 108  Gb/s PDM-QPSK signal is less than the pre-forward-error-correction threshold of 3.8×10(-3) after both 1 m wireless delivery at 100 GHz and 80 km single-mode fiber-28 transmission. To our knowledge, this is the first demonstration to realize 100  Gb/s signal delivery through both fiber and wireless links at 100 GHz.

  1. MMIC Amplifiers for 90 to 130 GHz

    Science.gov (United States)

    Samoska, Lorene; Pukala, David; Peralta, Alejandro; Bryerton, Eric; Morgan, Matt; Boyd, T.; Hu, Ming; Schmitz, Adele

    2007-01-01

    This brief describes two monolithic microwave integrated-circuit (MMIC) amplifier chips optimized to function in the frequency range of 90 to 130 GHz, covering nearly all of F-band (90 - 140 GHz). These amplifiers were designed specifically for local-oscillator units in astronomical radio telescopes such as the Atacama Large Millimeter Array (ALMA). They could also be readily adapted for use in electronic test equipment, automotive radar systems, and communications systems that operate between 90 and 130 GHz.

  2. High-frequency FeCoNiNbB-SiO{sub 2} nano-granular films with high resistivity and adjustable resonance frequency from 1.3 to 7.8 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bangmin; Wang, Guowei; Zhang, Feng; Xiao, Yuhua; Ge, Shihui [Lanzhou University, Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou (China)

    2009-11-15

    A series of (FeCoNiNbB){sub x}-(SiO{sub 2}){sub 1-x} nano-granular thin films were fabricated by magnetron sputtering with different oblique incidence angles {theta}. High-resolution transmission electron micrographs show that the films consist of amorphous CoFeM (M=Ni,Nb,B) alloy particles with diameter about 2 nm surrounded by amorphous SiO{sub 2} matrix. Excellent soft magnetic properties have been achieved with a variable in-plane uniaxial magnetic anisotropy field H{sub k0}, which increases monotonically with {theta} and x, and decreases with the composition of B in FeCoM. For one typical sample of x=0.63 with {theta}=30 , H{sub ch} and H{sub ce} are 4.2 Oe and 5.4 Oe, respectively, {rho} reaches 12.5 m {omega} cm and 4 {pi} M{sub s} and H{sub k0} are 5.70 kG s and 92 Oe, respectively, which lead to a high ferromagnetic resonance frequency f{sub r} of 2.2 GHz. Based on the analysis of experimental results, two sources for the origin of the magnetic anisotropy, namely anisotropic magnetic coupling and orientation order of atomic pairs, are suggested. (orig.)

  3. Low-intensity electromagnetic irradiation of 70.6 and 73 GHz frequencies enhances the effects of disulfide bonds reducer on Escherichia coli growth and affects the bacterial surface oxidation-reduction state.

    Science.gov (United States)

    Torgomyan, Heghine; Trchounian, Armen

    2011-10-14

    Low-intensity electromagnetic irradiation (EMI) of 70.6 and 73 GHz frequencies (flux capacity - 0.06 mW cm(-2)) had bactericidal effects on Escherichia coli. This EMI (1h) exposure suppressed the growth of E. coli K-12(λ). The pH value (6.0-8.0) did not significantly affect the growth. The lag-phase duration was prolonged, and the growth specific rate was inhibited, and these effects were more noticeable after 73 GHz irradiation. These effects were enhanced by the addition of DL-dithiothreitol (DTT), a strong reducer of disulfide bonds in surface membrane proteins, which in its turn also has bactericidal effect. Further, the number of accessible SH-groups in membrane vesicles was markedly decreased by EMI that was augmented by N,N'-dicyclohexycarbodiimide and DTT. These results indicate a change in the oxidation-reduction state of bacterial cell membrane proteins that could be the primary membranous mechanism in the bactericidal effects of low-intensity EMI of the 70.6 and 73 GHz frequencies.

  4. An 8-10 GHz upconversion mixer, with a low-frequency calibration loop resulting in better than -73dbc in-band spurs

    NARCIS (Netherlands)

    Withagen, Johan C.J.G.; Annema, A.J.; Nauta, B.; Vliet, van F.E.

    2016-01-01

    An 8-10 GHz X-band upconversion quadrature mixer stage implemented in 250 nm SiGe BiCMOS is presented. Orthogonality of the spurious responses caused by clock feed through, I/Q mismatch and baseband harmonics after self-mixing was exploited to realize a baseband calibration scheme reducing all in-ba

  5. Highly-efficient 1-GHz-repetition-frequency femtosecond Yb3+:KY(WO42 laser for super-continuum generation

    Directory of Open Access Journals (Sweden)

    Leburn C.G.

    2013-03-01

    Full Text Available We present a 1.024-GHz-repetition-rate femtosecond Yb3+:KY(WO42 laser with 61% optical-to-optical efficiency and 69% slope efficiency, generating a supercontinuum of bandwidth 400 nm in silica photonic-crystal fibre. RIN measurements of the laser yielded values <0.1%.

  6. 338-GHz Semiconductor Amplifier Module

    Science.gov (United States)

    Samoska, Lorene A.; Gaier, Todd C.; Soria, Mary M.; Fung, King Man; Rasisic, Vesna; Deal, William; Leong, Kevin; Mei, Xiao Bing; Yoshida, Wayne; Liu, Po-Hsin; Uyeda, Jansen; Lai, Richard

    2010-01-01

    Research findings were reported from an investigation of new gallium nitride (GaN) monolithic millimeter-wave integrated circuit (MMIC) power amplifiers (PAs) targeting the highest output power and the highest efficiency for class-A operation in W-band (75-110 GHz). W-band PAs are a major component of many frequency multiplied submillimeter-wave LO signal sources. For spectrometer arrays, substantial W-band power is required due to the passive lossy frequency multipliers.

  7. Study of Atmospheric Environment Propagation Characteristics of Vehicular Radar Based on 79 GHz Frequency Band%基于79 GHz车载雷达的大气环境传播特性研究

    Institute of Scientific and Technical Information of China (English)

    荆亚萍; 康健

    2016-01-01

    针对79 GHz频带雷达在雾气、降雨、降雪等不同天气条件下雷达性能下降的问题,研究了基于79 GHz频带车载雷达的传播特性。评价了包括大气因素、降水(雾气、降雨、降雪)以及沙尘对该频段的影响,并仿真分析了该频带在不同环境条件下对车载雷达性能的影响。结果表明,不同天气条件对该频段雷达具有一定的衰减作用,同时降雨对79 GHz车载雷达具有较大的影响。该研究对开发和利用79 GHz频带,并为该频带进一步应用于智能交通系统提供了理论根据。%Radar performance is greatly impacted by atmospheric environment,the propagation characteristics, such as the fading due to atmosphere,frog,rain,snow,and sand are simulated based on 79 GHz frequency band. Radar performance in different weather conditions are also simulated and analyzed. Results show that 79 GHz frequency band radar has a certain attenuation under different weather conditions,and the rainfall is the main influence. This research provides a theoretical basis for further development and utilization of 79 GHz frequency band used in the intelligent transportation system.

  8. Complex permittivity, permeability and microwave absorbing studies of (Co{sub 2-x}Mn{sub x}) U-type hexaferrite for X-band (8.2-12.4 GHz) frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Meena, R.S.; Bhattachrya, Sudeshna [Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India); Chatterjee, Ratnamala, E-mail: ratnamalac@gmail.com [Department of Physics, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)

    2010-07-25

    In order to develop a new microwave absorbing material over the X-band (8.2-12.4 GHz) frequency range, polycrystalline samples of U-type hexaferrite series: Ba{sub 4}Co{sub 2-x}Mn{sub x}Fe{sub 36}O{sub 60}, with x varying from 0 to 2.0 in steps of 0.5, were prepared through conventional solid state reaction route. X-ray diffraction analysis was done to find the structural change with composition. The variation of electromagnetic parameters (complex permittivity {epsilon}* = {epsilon}' - j{epsilon}'' and complex permeability {mu}* = {mu}' - j{mu}'') and microwave absorbing properties were studied over the X-band frequency range with varying composition. Both dielectric loss ({epsilon}'') and magnetic loss ({mu}'') were found to decrease with increasing x, whereas the dielectric constant ({epsilon}') and magnetic permeability ({mu}') variations are reciprocal with Mn addition. Composition with x = 1, presenting a maximum value of microwave absorption of 99.84% (or reflection loss R{sub L} = -28.4 dB) at 8.45 GHz when sample thickness is 1.7 mm. This composition also offered wide band absorption (>96%) throughout the X-band frequencies where it can be used for suppressing electromagnetic interference and radar signature.

  9. Transmission system for distribution of video over long-haul optical point-to-point links using a microwave photonic filter in the frequency range of 0.01-10 GHz

    Science.gov (United States)

    Zaldívar Huerta, Ignacio E.; Pérez Montaña, Diego F.; Nava, Pablo Hernández; Juárez, Alejandro García; Asomoza, Jorge Rodríguez; Leal Cruz, Ana L.

    2013-12-01

    We experimentally demonstrate the use of an electro-optical transmission system for distribution of video over long-haul optical point-to-point links using a microwave photonic filter in the frequency range of 0.01-10 GHz. The frequency response of the microwave photonic filter consists of four band-pass windows centered at frequencies that can be tailored to the function of the spectral free range of the optical source, the chromatic dispersion parameter of the optical fiber used, as well as the length of the optical link. In particular, filtering effect is obtained by the interaction of an externally modulated multimode laser diode emitting at 1.5 μm associated to the length of a dispersive optical fiber. Filtered microwave signals are used as electrical carriers to transmit TV-signal over long-haul optical links point-to-point. Transmission of TV-signal coded on the microwave band-pass windows located at 4.62, 6.86, 4.0 and 6.0 GHz are achieved over optical links of 25.25 km and 28.25 km, respectively. Practical applications for this approach lie in the field of the FTTH access network for distribution of services as video, voice, and data.

  10. Influence of Ultrasonic Treatment on Electromagnetic Characteristicsof Composites Based on Multiwall Carbon Nanotubes at Wide Range of Frequencies (100 Hz – 258 GHz

    Directory of Open Access Journals (Sweden)

    A. Kachusova

    2016-10-01

    Full Text Available In the present paper, we investigated microwave properties of polymer composites based on multiwall carbon nanotubes. The multiwall carbon nanotubes used in the composite were about 9.4 nm and 18.4 nm in diameter. The results show that the ultrasonic treatment modifies the dielectric properties of the composite. The dependence of the real and imaginary parts of the permittivity of sonication time is non linear. The results showed that composite material based on nanotubes with a diameter of 9.4 nm has a dispersive region of dielectric permittivity at the range about 10 GHz.

  11. A 122 GHz SiGe active subharmonic mixer

    OpenAIRE

    2005-01-01

    A 122 GHz subharmonic mixer for a radar-based sensor has been realized.It is fabricated in SiGe: C-HBT technology with a transit frequency of about 200 GHz. The conversion gain of the mixer is 23 dB at aLO-frequency of 60GHz with +3 dBm of power and a RF-input of 122.5GHz.The measured SSB noise figure at 122.5GHz is 12 dB.

  12. Single-Barrier-Varactor 200-GHz Tripler

    Science.gov (United States)

    Choudhury, Debabani; Frerking, Margaret A.; Batelaan, Paul D.

    1994-01-01

    Single-barrier varactor in crossed waveguide serves as experimental frequency-tripling device with output at frequencies ranging from 186 to 207 GHz. Varactor has symmetrical capacitance-vs.-voltage characteristic and antisymmetrical dc current-vs.-voltage characteristic. As result, generates only odd-harmonic currents when radio-frequency voltage applied at zero dc bias.

  13. Electromagnetic irradiation of Enterococcus hirae at low-intensity 51.8- and 53.0-GHz frequencies: changes in bacterial cell membrane properties and enhanced antibiotics effects.

    Science.gov (United States)

    Torgomyan, Heghine; Ohanyan, Vahe; Blbulyan, Syuzanna; Kalantaryan, Vitaly; Trchounian, Armen

    2012-04-01

    Exposure to electromagnetic irradiation (EMI) of 51.8 and 53.0 GHz and low intensity (flux capacity of 0.06 mW cm(-2) ) for 1 h markedly decreased the energy-dependent H(+) and K(+) transport across membranes of Enterococcus hirae ATCC 9790. After EMI, there was also a significant decrease of overall and N,N'-dicyclohexylcarbodiimide (DCCD)-sensitive ATPase activity of the membrane vesicles. These measures were considerably lower at 53.0 GHz. EMI in combination with different antibiotics, such as ceftriaxone and kanamycin at their minimal inhibitory concentrations (100 and 200 μM, respectively), enhanced bacterial cell growth and altered their membrane transport properties. Total H(+) efflux was most sensitive to ceftriaxone but DCCD-inhibited H(+) efflux and total K(+) influx were sensitive to kanamycin. The results indicate that cell membrane proteins could be a target in the action of EMI and enhanced antibacterial effects in combination with antibiotics. The DCCD-sensitive F(0) F(1) -ATPase or this ATPase in combination with K(+) uptake protein probably plays a key role in these effects.

  14. Impact of High Power Interference Sources in Planning and Deployment of Wireless Sensor Networks and Devices in the 2.4 GHz Frequency Band in Heterogeneous Environments

    Directory of Open Access Journals (Sweden)

    Francisco Falcone

    2012-11-01

    Full Text Available In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven’s power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology.

  15. Design of 24 GHz automotive collision avoidance radar and intermediate frequency signal processing circuit%24 GHz车载防撞雷达及中频信号处理电路设计

    Institute of Scientific and Technical Information of China (English)

    姜兴; 刘涛

    2014-01-01

    介绍了 FMCW 雷达测距、测速原理和系统结构;并针对24 GHz 线性调频连续波汽车防撞雷达系统的信号处理问题,对雷达后端中频信号处理电路进行了相关的研究及实现。设计了相应的滤波电路、增益控制放大电路,并取得了良好的效果。该设计提高了防撞雷达系统的测量精度和距离,对汽车主动安全性能起到一定积极作用。%The principle of the measurement of the distance and velocity of the FMCW radar and the structure of the system are described in this paper. To solve the problems of the signal processing of the 24 GHz linear frequency modulation continuous wave automotive anti-collision radar system, the back-end intermediate frequency signal processing circuit is researched and implemented. The corresponding filter circuit and gain control amplifier circuit are designed , and a good result is achieved in improving the measure accuracy and distance of the collision avoidance radar system. This design is useful to improve the performance of the automobile active safety to some extent.

  16. Recent Tests on 117.5 GHz and 170 GHz Gyrotrons

    Directory of Open Access Journals (Sweden)

    Felch K.

    2015-01-01

    Full Text Available Two megawatt-class gyrotrons at frequencies of 117.5 GHz and 170 GHz have recently been fabricated and tested at CPI. The 117.5 GHz gyrotron was designed to produce up to 1.8 MW for 10-second pulses, and will be used for electron cyclotron heating and current drive on the DIII-D tokamak at General Atomics. The 170 GHz gyrotron is specified as a 500 kW CW system, but has been designed with the goal of generating up to 1 MW CW. Oak Ridge National Laboratory will use the gyrotron in ITER ECH transmission line testing.

  17. Research on Frequency Planning of 5.8GHz in Wi-Fi Network of Wireless City%5.8GHz频段在无线城市Wi-Fi网络中的规划探讨

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    At present, wireless city is rapidly deployed in China. Wi-Fi technology is one of the major realization schemes. According to the current Wi-Fi frequency situation, this paper introduces the band of 5.8GHz into the application of Wi-Fi network and discusses the solution to frequency allocation under the coexistence multiple Wi-Fi networks.%  目前我国正在迅速开展无线城市的建设,Wi-Fi技术是主要的实现手段之一。针对Wi-Fi频率现状,通过介绍5.8GHz频段在Wi-Fi网络中的应用,探讨了在多Wi-Fi网络共存情况下的频率分配思路和方法。

  18. Single-chip electron spin resonance detectors operating at 50 GHz, 92 GHz, and 146 GHz

    Science.gov (United States)

    Matheoud, Alessandro V.; Gualco, Gabriele; Jeong, Minki; Zivkovic, Ivica; Brugger, Jürgen; Rønnow, Henrik M.; Anders, Jens; Boero, Giovanni

    2017-05-01

    We report on the design and characterization of single-chip electron spin resonance (ESR) detectors operating at 50 GHz, 92 GHz, and 146 GHz. The core of the single-chip ESR detectors is an integrated LC-oscillator, formed by a single turn aluminum planar coil, a metal-oxide-metal capacitor, and two metal-oxide semiconductor field effect transistors used as negative resistance network. On the same chip, a second, nominally identical, LC-oscillator together with a mixer and an output buffer are also integrated. Thanks to the slightly asymmetric capacitance of the mixer inputs, a signal at a few hundreds of MHz is obtained at the output of the mixer. The mixer is used for frequency down-conversion, with the aim to obtain an output signal at a frequency easily manageable off-chip. The coil diameters are 120 μm, 70 μm, and 45 μm for the U-band, W-band, and the D-band oscillators, respectively. The experimental frequency noises at 100 kHz offset from the carrier are 90 Hz/Hz1/2, 300 Hz/Hz1/2, and 700 Hz/Hz1/2 at 300 K, respectively. The ESR spectra are obtained by measuring the frequency variations of the single-chip oscillators as a function of the applied magnetic field. The experimental spin sensitivities, as measured with a sample of α,γ-bisdiphenylene-β-phenylallyl (BDPA)/benzene complex, are 1 × 108 spins/Hz1/2, 4 × 107 spins/Hz1/2, 2 × 107 spins/Hz1/2 at 300 K, respectively. We also show the possibility to perform experiments up to 360 GHz by means of the higher harmonics in the microwave field produced by the integrated single-chip LC-oscillators.

  19. 60-GHz CMOS phase-locked loops

    CERN Document Server

    Cheema, Hammad M; van Roermund, Arthur HM

    2010-01-01

    The promising high data rate wireless applications at millimeter wave frequencies in general and 60 GHz in particular have gained much attention in recent years. However, challenges related to circuit, layout and measurements during mm-wave CMOS IC design have to be overcome before they can become viable for mass market. ""60-GHz CMOS Phase-Locked Loops"" focusing on phase-locked loops for 60 GHz wireless transceivers elaborates these challenges and proposes solutions for them. The system level design to circuit level implementation of the complete PLL, along with separate implementations of i

  20. Proportion-corrected scaled voxel models for Japanese children and their application to the numerical dosimetry of specific absorption rate for frequencies from 30 MHz to 3 GHz

    Science.gov (United States)

    Nagaoka, Tomoaki; Kunieda, Etsuo; Watanabe, Soichi

    2008-12-01

    The development of high-resolution anatomical voxel models of children is difficult given, inter alia, the ethical limitations on subjecting children to medical imaging. We instead used an existing voxel model of a Japanese adult and three-dimensional deformation to develop three voxel models that match the average body proportions of Japanese children at 3, 5 and 7 years old. The adult model was deformed to match the proportions of a child by using the measured dimensions of various body parts of children at 3, 5 and 7 years old and a free-form deformation technique. The three developed models represent average-size Japanese children of the respective ages. They consist of cubic voxels (2 mm on each side) and are segmented into 51 tissues and organs. We calculated the whole-body-averaged specific absorption rates (WBA-SARs) and tissue-averaged SARs for the child models for exposures to plane waves from 30 MHz to 3 GHz; these results were then compared with those for scaled down adult models. We also determined the incident electric-field strength required to produce the exposure equivalent to the ICNIRP basic restriction for general public exposure, i.e., a WBA-SAR of 0.08 W kg-1.

  1. Delivering Microwave Spectroscopy to the Masses: a Design of a Low-Cost Microwave Spectrometer Operating in the 18-26 GHZ Frequency Range

    Science.gov (United States)

    Steber, Amanda; Pate, Brooks

    2014-06-01

    Advances in chip-level microwave technology in the communications field have led to the possibilities of low cost alternatives for current Fourier transform microwave (FTMW) spectrometers. Many of the large, expensive microwave components in a traditional design can now be replaced by robust, mass market monolithic microwave integrated circuits (MMICs). "Spectrometer on a board" designs are now feasible that offer dramatic cost reduction for microwave spectroscopy. These chip-level components can be paired with miniature computers to produce compact instruments that are operable through USB. A FTMW spectrometer design using the key MMIC components that drive cost reduction will be presented. Two dual channel synthesizers (Valon Technology Model 5008), a digital pattern generator (Byte Paradigm Wav Gen Xpress), and a high-speed digitizer/arbitrary waveform generator combination unit (Tie Pie HS-5 530 XM) form the key components of the spectrometer for operation in the 18-26.5 GHz range. The design performance is illustrated using a spectrometer that is being incorporated into a museum display for astrochemistry. For this instrument a user interface, developed in Python, has been developed and will be shown.

  2. 105 GHz Notch Filter Design for Collective Thomson Scattering

    DEFF Research Database (Denmark)

    Furtula, Vedran; Michelsen, Poul; Leipold, Frank;

    2011-01-01

    A millimeter-wave notch filter with 105-GHz center frequency, >20-GHz passband coverage, and 1-GHz rejection bandwidth has been constructed. The design is based on a fundamental rectangular waveguide with cylindrical cavities coupled by narrow iris gaps, i.e., small elongated holes of negligible...... thickness. We use numerical simulations to study the sensitivity of the notch filter performance to changes in geometry and in material conductivity within a bandwidth of ±10 GHz. The constructed filter is tested successfully using a vector network analyzer monitoring a total bandwidth of 20 GHz...

  3. Transient DNA damage induced by high-frequency electromagnetic fields (GSM 1.8 GHz) in the human trophoblast HTR-8/SVneo cell line evaluated with the alkaline comet assay.

    Science.gov (United States)

    Franzellitti, Silvia; Valbonesi, Paola; Ciancaglini, Nicola; Biondi, Carla; Contin, Andrea; Bersani, Ferdinando; Fabbri, Elena

    2010-01-05

    One of the most controversial issue regarding high-frequency electromagnetic fields (HF-EMF) is their putative capacity to affect DNA integrity. This is of particular concern due to the increasing use of HF-EMF in communication technologies, including mobile phones. Although epidemiological studies report no detrimental effects on human health, the possible disturbance generated by HF-EMF on cell physiology remains controversial. In addition, the question remains as to whether cells are able to compensate their potential effects. We have previously reported that a 1-h exposure to amplitude-modulated 1.8 GHz sinusoidal waves (GSM-217 Hz, SAR=2 W/kg) largely used in mobile telephony did not cause increased levels of primary DNA damage in human trophoblast HTR-8/SVneo cells. Nevertheless, further investigations on trophoblast cell responses after exposure to GSM signals of different types and durations were considered of interest. In the present work, HTR-8/SVneo cells were exposed for 4, 16 or 24h to 1.8 GHz continuous wave (CW) and different GSM signals, namely GSM-217 Hz and GSM-Talk (intermittent exposure: 5 min field on, 10 min field off). The alkaline comet assay was used to evaluate primary DNA damages and/or strand breaks due to uncompleted repair processes in HF-EMF exposed samples. The amplitude-modulated signals GSM-217 Hz and GSM-Talk induced a significant increase in comet parameters in trophoblast cells after 16 and 24h of exposure, while the un-modulated CW was ineffective. However, alterations were rapidly recovered and the DNA integrity of HF-EMF exposed cells was similar to that of sham-exposed cells within 2h of recovery in the absence irradiation. Our data suggest that HF-EMF with a carrier frequency and modulation scheme typical of the GSM signal may affect the DNA integrity.

  4. Radio frequency electromagnetic radiation (RF-EMR from GSM (0.9/1.8GHz mobile phones induces oxidative stress and reduces sperm motility in rats

    Directory of Open Access Journals (Sweden)

    Maneesh Mailankot

    2009-06-01

    Full Text Available INTRODUCTION: Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices. OBJECTIVE: The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality. MATERIALS AND METHODS: Male albino Wistar rats (10-12 weeks old were exposed to RF-EMR from an active GSM (0.9/1.8 GHz mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested. RESULTS: One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis. CONCLUSION: Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility.

  5. Gyrotrons for magnetic fusion applications at 110 GHz and 170 GHz

    Directory of Open Access Journals (Sweden)

    Cahalan P.

    2012-09-01

    Full Text Available Two megawatt-class gyrotrons at frequencies of 110 GHz and 170 GHz have recently been fabricated at CPI. The 110 GHz gyrotron is designed to produce 1.2 MW of output power for 10-second pulses, and will be used for electron cyclotron heating and current drive on the DIII-D tokamak at General Atomics. This gyrotron has completed factory testing and has been delivered to General Atomics for installation and additional testing. The 170 GHz gyrotron, though specified as a 500 kW CW system, has been designed with the goal of generating up to 1 MW CW. Oak Ridge National Laboratory will use this gyrotron in ITER ECH transmission line testing. This gyrotron has been fabricated and is awaiting factory testing, Design features of each gyrotron are described, and test data for the 110 GHz gyrotron are presented.

  6. Wearable slot antenna at 2.45 GHz for off-body radiation: Analysis of efficiency, frequency shift, and body absorption.

    Science.gov (United States)

    Fernandez, Marta; Espinosa, Hugo G; Thiel, David V; Arrinda, Amaia

    2017-09-12

    The interaction of body-worn antennas with the human body causes a significant decrease in antenna efficiency and a shift in resonant frequency. A resonant slot in a small conductive box placed on the body has been shown to reduce these effects. The specific absorption rate is less than international health standards for most wearable antennas due to small transmitter power. This paper reports the linear relationship between power absorbed by biological tissues at different locations on the body and radiation efficiency based on numerical modeling (r = 0.99). While the -10 dB bandwidth of the antenna remained constant and equal to 12.5%, the maximum frequency shift occurred when the antenna was close to the elbow (6.61%) and on the thigh (5.86%). The smallest change was found on the torso (4.21%). Participants with body-mass index (BMI) between 17 and 29 kg/m(2) took part in experimental measurements, where the maximum frequency shift was 2.51%. Measurements showed better agreement with simulations on the upper arm. These experimental results demonstrate that the BMI for each individual had little effect on the performance of the antenna. Bioelectromagnetics. 2017;9999:XX-XX. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. Subharmonic resonant optical excitation of confined acoustic modes in a free-standing semiconductor membrane at GHz frequencies with a high-repetition-rate femtosecond laser.

    Science.gov (United States)

    Bruchhausen, A; Gebs, R; Hudert, F; Issenmann, D; Klatt, G; Bartels, A; Schecker, O; Waitz, R; Erbe, A; Scheer, E; Huntzinger, J-R; Mlayah, A; Dekorsy, T

    2011-02-18

    We propose subharmonic resonant optical excitation with femtosecond lasers as a new method for the characterization of phononic and nanomechanical systems in the gigahertz to terahertz frequency range. This method is applied for the investigation of confined acoustic modes in a free-standing semiconductor membrane. By tuning the repetition rate of a femtosecond laser through a subharmonic of a mechanical resonance we amplify the mechanical amplitude, directly measure the linewidth with megahertz resolution, infer the lifetime of the coherently excited vibrational states, accurately determine the system's quality factor, and determine the amplitude of the mechanical motion with femtometer resolution.

  8. The specific absorption rate of tissues in rats exposed to electromagnetic plane waves in the frequency range of 0.05-5 GHz and SARwb in free-moving rats.

    Science.gov (United States)

    Chen, Bingxin; Wang, Jiamin; Qi, Hongxin; Zhang, Jie; Chen, Shude; Wang, Xianghui

    2017-03-01

    As electromagnetic exposure experiments can only be performed on small animals, usually rats, research on the characteristics of specific absorption rate (SAR) distribution in the rat has received increasing interest. A series of calculations, which simulated the SAR in a male rat anatomical model exposed to electromagnetic plane waves ranging from 0.05 to 5 GHz with different incidence and polarization, were conducted. The whole-body-averaged SAR (SARwb) and the tissue-averaged SAR (SARavg) in 20 major tissues were determined. Results revealed that incidence has great impact on SAR in the rat at higher frequencies owing to the skin effect and the effect on SARavg in tissues is much more apparent than that on SARwb; while polarization plays an important role under lower frequencies. Not only the incidence, but also the polarization in the rat keeps changing when the rat is in free movement. Thus, this article discussed a convenient way to obtain relatively accurate SARwb in a free-moving rat.

  9. New high-performance complementary bipolar technology featuring 45-GHz NPN and 20-GHz PNP devices

    Science.gov (United States)

    Wilson, Martin C.; Osborne, Peter H.; Thomas, Simon; Cook, Trevor

    1999-09-01

    A new high performance silicon complementary bipolar technology is introduced. In addition a novel process 'enhancement' technique based on a local oxidation is described and demonstrated and NPN devices with cut-off frequencies up to 45GHz and PNP devices of 20GHz have been fabricate. We propose that the technique we have used will allow specific transistors within a circuit to be optimized, as required.

  10. Effects of Electromagnetic Field Over a Human Body, Sar Simulation with and Without Nanotextile in the Frequency Range 0.9-1.8GHZ

    Science.gov (United States)

    Tomovski, Boyan; Gräbner, Frank; Hungsberg, Axel; Kallmeyer, Christian; Linsel, Mario

    2011-11-01

    Within only the last decade, usage of mobile phones and many other electronic devices with high speed wireless RF connection is rapidly increasing. Modern life requires reliable, quick and high-quality information connections, which explains the widely spreading craze for electronic mobile devices of various types. The vast technological advances we are witnessing in electronics, electro-optics, and computer science have profoundly affected our everyday lives. Meanwhile, safety concerns regarding the biological effects of electromagnetic (EM) radiation have been raised, in particular at a low level of exposure which we everyday experience. A variety of waves and signals have to be considered such as different sine waves, digital signals used in radio, television, mobile phone systems and other information transfer systems. The field around us has become rather complicated and the "air space is getting more and more dense with RF. The establishing of safety recommendations, law norms and rules augmented by adequate measurements is very important and requires quite an expertise. But as many scientific researches suggest, what we are currently witnessing is very likely to generate a great public danger and a bad influence over the human body. There are many health organisations warning the public for possible development of cancer, mental and physical disorders etc [7, 8]. These suggestions are quite serious and should not be neglected by the official bodies and the test laboratories. In the following work, the effects of electromagnetic field over a virtual model of a human head have been simulated in the frequency range from 900 MHz to 1800 MHz (commonly created in the real life by mobile GSM system) with the help of the program MEFiSTo 2D Classic [1]. The created virtual models using the 2D simulation & computation software proved that the use of new high tech nanotextile materials for shielding layers around the human body can reduce the effects of EM fields

  11. Traveling-Wave Maser for 32 GHz

    Science.gov (United States)

    Shell, James; Clauss, Robert

    2009-01-01

    The figure depicts a traveling-wave ruby maser that has been designed (though not yet implemented in hardware) to serve as a low-noise amplifier for reception of weak radio signals in the frequency band of 31.8 to 32.3 GHz. The design offers significant improvements over previous designs of 32-GHz traveling-wave masers. In addition, relative to prior designs of 32-GHz amplifiers based on high-electron-mobility transistors, this design affords higher immunity to radio-frequency interference and lower equivalent input noise temperature. In addition to the basic frequency-band and low-noise requirements, the initial design problem included a requirement for capability of operation in a closed-cycle helium refrigerator at a temperature .4 K and a requirement that the design be mechanically simplified, relative to prior designs, in order to minimize the cost of fabrication and assembly. Previous attempts to build 32- GHz traveling-wave masers involved the use of metallic slow-wave structures comprising coupled transverse electromagnetic (TEM)-mode resonators that were subject to very tight tolerances and, hence, were expensive to fabricate and assemble. Impedance matching for coupling signals into and out of these earlier masers was very difficult. A key feature of the design is a slow-wave structure, the metallic portions of which would be mechanically relatively simple in that, unlike in prior slow-wave structures, there would be no internal metal steps, irises, or posts. The metallic portions of the slow-wave structure would consist only of two rectangular metal waveguide arms. The arms would contain sections filled with the active material (ruby) alternating with evanescent-wave sections. This structure would be transparent in both the signal-frequency band (the aforementioned range of 31.8 to 32.3 GHz) and the pump-frequency band (65.75 to 66.75 GHz), and would impose large slowing factors in both frequency bands. Resonant ferrite isolators would be placed in the

  12. Low Cost Automated Module Assembly for 180 GHz Devices Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Emergence of Indium Phosphide IC's has made possible devices operating at frequencies up to 200GHZ and beyond. Building modules using these devices opens a goldmine...

  13. The 18/30 GHz fixed communications system service demand assessment. Volume 1: Executive summary

    Science.gov (United States)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for voice, video, and data communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is discussed. Major study objectives, overall methodology, results, and general observations about a satellite systems market characteristics and trends are summarized.

  14. A 75-116-Ghz LNA with 23-K Noise Temperature at 108 Ghz

    Science.gov (United States)

    Varonen, Mikko; Reeves, Rodrigo; Kangaslahti, Pekka; Samoska, Lorene; Cleary, Kieran; Gawande, Rohit; Fung, Andy; Gaier, Todd; Weinreb, Sander; Readhead, Anthony C. S.; Sarkozy, Stephen; Lai, Richard

    2013-01-01

    In this paper we present the design and measurement results, both on-wafer and in package, of an ultra-low-noise and wideband monolithic microwave integrated circuit (MMIC) amplifier in the frequency range of 75 to 116 GHz. The three-stage amplifier packaged in a WR10 waveguide housing and fabricated using a 35-nm InP HEMT technology achieves a record noise temperature of 23 K at 108 GHz when cryogenically cooled to 27 K. The measured gain is 22 to 27 dB for frequency range of 75 to 116 GHz. Furthermore, the amplifier utilizes four finger devices with total gate width of 60 um resulting for improved linearity.

  15. Design and measurement of a 53 GHz balanced Colpitts oscillator

    Institute of Scientific and Technical Information of China (English)

    Zhao Yan; Wang Zhigong; Li Wei; Zhang Li

    2009-01-01

    A 53 GHz Colpitts oscillator implemented in a SiGe:C BiCMOS technology is presented. Limited by a 26.5 GHz frequency analyzer, the oscillator was measured indirectly through an on-chip mixer. The mixer down-converted the oscillating frequency to an intermediate frequency (IF) below 26.5 GHz. By adjusting the local os-cillating (LO) frequency and recording the changes of IF frequency, the oscillator's output frequency (RF) was determined. Additionally, using phase noise theory of mixers, the oscillator's phase noise was estimated as-58 dBc/Hz at 1 MHz offset and the output power was about-21 dBm. The chip is 270×480 μm in size.

  16. SEVENTH HARMONIC 20 GHz CO-GENERATOR

    Energy Technology Data Exchange (ETDEWEB)

    Hirshfield, Jay L

    2014-04-08

    To satisfy the need for multi-MW rf sources in frequency ranges where commercial sources do not exist, a study was undertaken on a class of devices based on gyro-harmonic frequency multiplication. This mechanism relies upon adding energy in gyrating motion to a linear electron beam that traverses a rotating-mode TE111-mode drive cavity in a dc magnetic field. The beam then drifts along the magnetic field into a second cavity, operating in the TEn11-mode tuned to the nth harmonic of the drive cavity. Studies of this configuration have been carried out for 2 < n < 7. Results are given for multi-MW, efficient operation of a 7th harmonic device operating at 20 GHz, and a 2nd harmonic device operating at 22.4 GHz.

  17. A 1.2 V and 69 mW 60 GHz Multi-channel Tunable CMOS Receiver Design

    Directory of Open Access Journals (Sweden)

    A. Oncu

    2015-04-01

    Full Text Available A multi-channel receiver operating between 56 GHz and 70 GHz for coverage of different 60 GHz bands worldwide is implemented with a 90 nm Complementary Metal-Oxide Semiconductor (CMOS process. The receiver containing an LNA, a frequency down-conversion mixer and a variable gain amplifier incorporating a band-pass filter is designed and implemented. This integrated receiver is tested at four channels of centre frequencies 58.3 GHz, 60.5 GHz, 62.6 GHz and 64.8 GHz, employing a frequency plan of an 8 GHz-intermediate frequency (IF. The achieved conversion gain by coarse gain control is between 4.8 dB–54.9 dB. The millimeter-wave receiver circuit is biased with a 1.2V supply voltage. The measured power consumption is 69 mW.

  18. 30/20 GHz and 6/4 GHz band transponder development for communications satellite CS-3

    Science.gov (United States)

    Tanaka, Masayoshi; Nakamura, Makoto; Okamoto, Teruki; Kumazawa, Hiroyuki

    The next phase communications satellite CS-3 will be launched in 1988 as a successor to CS-2. The CS-3 is composed of two 6/4 GHz band and ten 30/20 GHz band transponders and its mission life is seven years. This paper describes the newly developed CS-3 transponder, especially a 4 GHz band 7 watt GaAs FET amplifier, Ka-band frequency single-conversion, a 30 GHz band low noise amplifier, and a 20 GHz band 10 watt TWTA. The introduction of these new technologies contributes significantly to reducing the CS-3 transponder weight and size, and to improving performance characteristics and insuring a long life.

  19. A 90-GHz Photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, D.T.; Hogan, M.J.; /SLAC; Ferrario, M.; Serafini, L.; /Frascati /INFN, Milan

    2005-09-12

    Photocathode rf guns depend on mode locked laser systems to produce an electron beam at a given phase of the rf. In general, the laser pulse is less than {sigma}{sub z} = 10{sup o} of rf phase in length and the required stability is on the order of {Delta}{phi} = 1{sup o}. At 90 GHz (W-band), these requirements correspond to {sigma}{sub z} = 333 fsec and {Delta}{phi} = 33 fsec. Laser system with pulse lengths in the fsec regime are commercially available, the timing stability is a major concern. We propose a multi-cell W-band photoinjector that does not require a mode locked laser system. Thereby eliminating the stability requirements at W-band. The laser pulse is allowed to be many rf periods long. In principle, the photoinjector can now be considered as a thermionic rf gun. Instead of using an alpha magnet to compress the electron bunch, which would have a detrimental effect on the transverse phase space quality due to longitudinal phase space mixing, we propose to use long pulse laser system and a pair of undulators to produce a low emittance, high current, ultra-short electron bunch for beam dynamics experiments in the 90 GHz regime.

  20. A 90 GHz photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, D.T.; Hogan, M.J. [SLAC, Stanford, CA (United States); Ferrario, M. [Istituto Nazionale di Fisica Nucleare, Frascati, RM (Italy); Serafini, L. [Istituto Nazionale di Fisica Nucleare, Milan (Italy)

    1999-07-01

    Photocathode rf guns depend on mode locked laser systems to produce an electron beam at a given phase of the rf. In general, the laser pulse is less than {sigma}{sub 2} = 10 degrees of rf phase in length and the required stability is on the order of {delta}{phi} = 1degree. At 90 GHz (W-band), these requirements correspond to {sigma}{sub 2} = 333 fsec and {delta}{phi} = 33 fsec. Laser system with pulse lengths in the fsec regime are commercially available, the timing stability is a major concern. It is proposed a multi-cell W-band photoinjector that does not require a mode locked laser system. Thereby eliminating the stability requirements at W-band. The laser pulse is allowed to be many rf periods long. In principle, the photoinjector can now be considered as a thermionic rf gun. Instead of using an alpha magnet to compress the electron bunch, which would have a detrimental effect on the transverse hase space quality due to longitudinal phase space mixing, it is here proposed to use long pulse laser system and a pair of undulators to produce a low emittance, high current, ultra-short electron bunch for beam dynamics experiments in the 90 GHz regime.

  1. 17 and 24 GHz observations of southern pulsars

    CERN Document Server

    Keith, M J; Levin, L; Bailes, M

    2011-01-01

    We present observations of PSRs J0437-4715, J0738-4042, J0835-4510, J0908-4913, J1048-5832, J1622-4950, J1644-4559, J1721-3532 and J1740-3015 at 17 GHz using the Parkes radio telescope. All 9 were detected at 17 GHz, additionally, we detected PSR J0835-4510 and J1622-4950 at 24 GHz. Polarisation profiles of each pulsar and the variation with frequency are discussed. In general, we find that the highly polarised edge components of young pulsars continue to dominate their profiles at 17 GHz. Older pulsars (>10^5 years) appear to be almost completely depolarised. Our detection of PSR J0437-4715 is the highest frequency observation of a millisecond pulsar to date, and implies a luminosity at 17 GHz of 14 {\\mu}Jy kpc^2, and a mean spectral index of 2.2. We find that the spectral index of the magnetar PSR J1622-4950 is flat between 1.4 and 24 GHz, similar to the other known radio magnetars XTE J1810-197 and 1E 1547.0-5408. The profile is similar to that at 3.1 GHz, and is highly linearly polarised. Analysis of the ...

  2. 600-GHz Electronically Tunable Vector Measurement System

    Science.gov (United States)

    Dengler, Robert; Maiwald, Frank; Siegel, Peter

    2007-01-01

    A compact, high-dynamic-range, electronically tunable vector measurement system that operates in the frequency range from approximately 560 to approximately 635 GHz has been developed as a prototype of vector measurement systems that would be suitable for use in nearly-real-time active submillimeter-wave imaging. As used here, 'vector measurement system" signifies an instrumentation system that applies a radio-frequency (RF) excitation to an object of interest and measures the resulting amplitude and phase response, relative to either the applied excitatory signal or another reference signal related in a known way to applied excitatory signal.

  3. 60 GHz SIW Steerable Antenna Array in LTCC

    Institute of Scientific and Technical Information of China (English)

    Bahram Sanadgol; Sybille Holzwarth; Peter Uhlig; Alberto Milano; Raft Popovich

    2012-01-01

    In this paper, we present a 60 GHz substrate-integrated waveguide fed-steerable low-temperature cofired ceramics array. The antenna is suitable for transmitting and receiving on the 60 GHz wireless personal area network frequency band. The wireless system can be used for HDTV, high-data-rate networking up to 4.5 GBit/s, security and surveillance, and similar applications.

  4. A varactor tuned low-cost 24 GHz harmonic VCO

    Directory of Open Access Journals (Sweden)

    M. O. Olbrich

    2006-01-01

    Full Text Available We present a low-cost 24 GHz VCO that is based on a microstrip design combined with discrete packaged devices. The output frequency is generated by a harmonic oscillator. The tunabilty was reached using a varactor diode. Two versions of the VCO were built, one has a wide tuning range of 1.1 GHz and the other one has a high output power of 3.7 dBm.

  5. A 2.3/3.3 GHz Dual Band Antenna Design for WiMax Applications

    Directory of Open Access Journals (Sweden)

    Adit Kurniawan

    2010-11-01

    Full Text Available A triangular-slot antenna with rectangular patch for 2.3/3.3 GHz WiMax applications has been implemented on DICLAD 527 substrate (relative permittivity εr = 2.5 with 1.524 mm of substrate thickness. A rectangular patch printed on one side of the substrate is fed by a 50 Ω microstrip line and acts as the frequency tuning stub, while the triangular slot is positioned on the opposite side of the substrate, center lined to the rectangular stub. From the measurement results based on VSWR = 2 or equal to the return loss of 9.53 dB, at the lower band of 2.3 GHz the resulting impedance bandwidth is 290 MHz (from 2.16 to 2.45 GHZ and at the upper band of 3.3 GHz is 370 MHz (from 3.31 to 3.68GHz, providing services for 2.3 GHz and 3.3 GHz frequency bands allocated for WiMax applications. The antenna gain measurement at 2.3 GHz frequency band is almost agrees with the simulation result of 3.2 dBi. While at 3.3 GHz the gain is approximately 4.4 dBi and continues to decrease with increasing frequency. The antenna gain measurement achieves maximum of 4.8 dBi (6 dBi from simulation at about 3 GHz. The simulation and measurement results are evaluated and discussed.

  6. Analysis of 38 GHz mmWave Propagation Characteristics of Urban Scenarios

    DEFF Research Database (Denmark)

    Rodriguez Larrad, Ignacio; Nguyen, Huan Cong; Sørensen, Troels Bundgaard

    2015-01-01

    The 38 GHz mm-wave frequency band is a strong candidate for the future deployment of wireless systems. Compared to lower frequency bands, propagation in the 38 GHz band is relatively unexplored for access networks in urban scenarios. This paper presents a detailed measurement-based analysis of ur...

  7. A novel scheme to generate 40-GHz CSRZ pulse trains using a 10-GHz dual-parallel Mach-Zehnder modulator

    Institute of Scientific and Technical Information of China (English)

    Yanfei Xing; Caiyun Lou

    2011-01-01

    A new technique to generate 40-GHz carrier-suppressed return-to-zero (CSRZ) optical pulse trains using only a 10-GHz dual-parallel Mach-Zehnder modulator (MZM) is presented and experimentally demonstrated. The spectrum of the generated CSRZ pulses is calculated by simulation and compared with conventional MZM-based RZ and CSRZ pulse trains. The experimental results demonstrate that CSRZ pulse trains are obtained, and that the carrier and the unwanted 20-GHz low-frequency component are suppressed by 25 dB. The technique can also be extended to 160-GHz CSRZ pulse generation when 40-GHz devices are employed.%@@ A new technique to generate 40-GHz carrier-suppressed return-to-zero (CSRZ) optical pulse trains using only a 10-GHz dual-parallel Mach-Zehnder modulator (MZM) is presented and experimentally demonstrated. The spectrum of the generated CSRZ pulses is calculated by simulation and compared with conventional MZM-based RZ and CSRZ pulse trains. The experimental results demonstrate that CSRZ pulse trains are obtained, and that the carrier and the unwanted 20-GHz low-frequency component are suppressed by 25 dB. The technique can also be extended to 160-GHz CSRZ pulse generation when 40-GHz devices are employed.

  8. 670 GHz Schottky Diode Based Subharmonic Mixer with CPW Circuits and 70 GHz IF

    Science.gov (United States)

    Chattopadhyay, Goutam (Inventor); Schlecht, Erich T. (Inventor); Lee, Choonsup (Inventor); Lin, Robert H. (Inventor); Gill, John J. (Inventor); Sin, Seth (Inventor); Mehdi, Imran (Inventor)

    2014-01-01

    A coplanar waveguide (CPW) based subharmonic mixer working at 670 GHz using GaAs Schottky diodes. One example of the mixer has a LO input, an RF input and an IF output. Another possible mixer has a LO input, and IF input and an RF output. Each input or output is connected to a coplanar waveguide with a matching network. A pair of antiparallel diodes provides a signal at twice the LO frequency, which is then mixed with a second signal to provide signals having sum and difference frequencies. The output signal of interest is received after passing through a bandpass filter tuned to the frequency range of interest.

  9. Development of 30/20 GHz satellite antenna structures

    Science.gov (United States)

    Minomo, M.; Yasaka, T.

    1986-08-01

    An antenna structural design for a large capacity communication satellite using 13 beams in the 30/20GHz frequency bands is discussed. This design is to be utilized in developing a more cost effective domestic satellite communication system for Japan. This system requires 2 high precision deployable antennas with projected aperture diameters of 3.5m at 20GHz and 2.5m at 30GHz. The in-orbit demonstration will use the ETS-6 satellite. Based on experience in the development of spaceborne antennas for 30/20GHz bands (e.g., for the CS-2 and CS-3 satellites) activities in structural design of high precision deployable antennas show the truss reflector structure is promising for achieving required structural properties.

  10. 146-GHz millimeter-wave radio-over-fiber photonic wireless transmission system.

    Science.gov (United States)

    Fice, M J; Rouvalis, E; van Dijk, F; Accard, A; Lelarge, F; Renaud, C C; Carpintero, G; Seeds, A J

    2012-01-16

    We report the experimental implementation of a wireless transmission system with a 146-GHz carrier frequency which is generated by optical heterodyning the two modes from a monolithically integrated quantum dash dual-DFB source. The monolithic structure of the device and the inherent low noise characteristics of quantum dash gain material allow us to demonstrate the transmission of a 1 Gbps ON-OFF keyed data signal with the two wavelengths in a free-running state at 146-GHz carrier wave frequency. The tuning range of the device fully covers the W-band (75 - 110 GHz) and the F-band (90 - 140 GHz).

  11. A monolithic integrated 180 GHz SiGe HBT Push-Push Oscillator.

    OpenAIRE

    Roux, P.; BAEYENS, Y.; Wohlgemuth, O.; Chen, Y.K.

    2005-01-01

    A fully integrated single-ended output push-push oscillator is realized using an advanced 0.2µm SiGe HBT process. Up to –5 dBm output power is achieved at 180 GHz using a technology with a transition frequency fT of 200 GHz and maximum oscillation frequency fMAX of 275 GHz. Preliminary phase noise measurements show a phase noise of less than –90 dBc/Hz at 1 MHz offset from the 180 GHz carrier.

  12. EVIDENCE FOR ANOMALOUS DUST-CORRELATED EMISSION AT 8 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Michelle; Page, Lyman [Department of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544-0708 (United States); Dunkley, Joanna [Sub-department of Astrophysics, University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)

    2012-04-20

    In 1969 Edward Conklin measured the anisotropy in celestial emission at 8 GHz with a resolution of 16.{sup 0}2 and used the data to report a detection of the cosmic microwave background dipole. Given the paucity of 8 GHz observations over large angular scales and the clear evidence for non-power-law Galactic emission near 8 GHz, a new analysis of Conklin's data is informative. In this paper, we compare Conklin's data to that from Haslam et al. (0.4 GHz), Reich and Reich (1.4 GHz), and the Wilkinson Microwave Anisotropy Probe (WMAP; 23-94 GHz). We show that the spectral index between Conklin's data and the 23 GHz WMAP data is {beta} = -1.7 {+-} 0.1, where we model the emission temperature as T{proportional_to}{nu}{sup {beta}}. Free-free emission has {beta} Almost-Equal-To - 2.15 and synchrotron emission has {beta} Almost-Equal-To - 2.7 to -3. Thermal dust emission ({beta} Almost-Equal-To 1.7) is negligible at 8 GHz. We conclude that there must be another distinct non-power-law component of diffuse foreground emission that emits near 10 GHz, consistent with other observations in this frequency range. By comparing to the full complement of data sets, we show that a model with an anomalous emission component, assumed to be spinning dust, is preferred over a model without spinning dust at 5{sigma} ({Delta}{chi}{sup 2} = 31). However, the source of the new component cannot be determined uniquely.

  13. Gaussian entanglement distribution with GHz bandwidth

    CERN Document Server

    Ast, Stefan; Mehmet, Moritz; Schnabel, Roman

    2016-01-01

    The distribution of Gaussian entanglement can be used to generate a mathematically-proven secure key for quantum cryptography. The distributed secret key rate is limited by the bandwidth of the nonlinear resonators used for entanglement generation, which is less than 100 MHz for current state-of-the-art setups. The development of an entanglement source with a higher bandwidth promises an increased measurement speed and a linear boost in the secure data rate. Here, we present the experimental realization of a continuous-variable entanglement source with a bandwidth of more than 1.25 GHz. The measured entanglement spectrum was quantified via the inseparability criterion introduced by Duan and coworkers with a critical value of 4 below which entanglement is certified. The measurements yielded an inseparability value of about 1.8 at a frequency of 300 MHz to about 2.8 at 1.2 GHz extending further to about 3.1 at 1.48 GHz. In the experiment we used two 2.6 mm long monolithic PPKTP crystal resonators to generate tw...

  14. High-purity 60GHz band millimeter-wave generation based on optically injected semiconductor laser under subharmonic microwave modulation.

    Science.gov (United States)

    Fan, Li; Xia, Guangqiong; Chen, Jianjun; Tang, Xi; Liang, Qing; Wu, Zhengmao

    2016-08-08

    Based on an optically injected semiconductor laser (OISL) operating at period-one (P1) nonlinear dynamical state, high-purity millimeter-wave generation at 60 GHz band is experimentally demonstrated via 1/4 and 1/9 subharmonic microwave modulation (the order of subharmonic is with respect to the frequency fc of the acquired 60 GHz band millimeter-wave but not the fundamental frequency f0 of P1 oscillation). Optical injection is firstly used to drive a semiconductor laser into P1 state. For the OISL operates at P1 state with a fundamental frequency f0 = 49.43 GHz, by introducing 1/4 subharmonic modulation with a modulation frequency of fm = 15.32 GHz, a 60 GHz band millimeter-wave with central frequency fc = 61.28 GHz ( = 4fm) is experimentally generated, whose linewidth is below 1.6 kHz and SSB phase noise at offset frequency 10 kHz is about -96 dBc/Hz. For fm is varied between 13.58 GHz and 16.49 GHz, fc can be tuned from 54.32 GHz to 65.96 GHz under matched modulation power Pm. Moreover, for the OISL operates at P1 state with f0 = 45.02 GHz, a higher order subharmonic modulation (1/9) is introduced into the OISL for obtaining high-purity 60 GHz band microwave signal. With (fm, Pm) = (7.23 GHz, 13.00 dBm), a microwave signal at 65.07 GHz ( = 9fm) with a linewidth below 1.6 kHz and a SSB phase noise less than -98 dBc/Hz is experimentally generated. Also, the central frequency fc can be tuned in a certain range through adjusting fm and selecting matched Pm.

  15. Rain rate and modeled fade distributions at 20 GHz and 30 GHz derived from five years of network rain gauge measurements

    Science.gov (United States)

    Goldhirsh, Julius; Krichevsky, Vladimir; Gebo, Norman

    1992-01-01

    Five years of rain rate and modeled slant path attenuation distributions at 20 GHz and 30 GHz derived from a network of 10 tipping bucket rain gages was examined. The rain gage network is located within a grid 70 km north-south and 47 km east-west in the Mid-Atlantic coast of the United States in the vicinity of Wallops Island, Virginia. Distributions were derived from the variable integration time data and from one minute averages. It was demonstrated that for realistic fade margins, the variable integration time results are adequate to estimate slant path attenuations at frequencies above 20 GHz using models which require one minute averages. An accurate empirical formula was developed to convert the variable integration time rain rates to one minute averages. Fade distributions at 20 GHz and 30 GHz were derived employing Crane's Global model because it was demonstrated to exhibit excellent accuracy with measured COMSTAR fades at 28.56 GHz.

  16. Continuum observation of Sagittarius B2 at 23 and 43 GHz

    Science.gov (United States)

    Akabane, Kenji; Sofue, Yoshiaki; Hirabayashi, Hisashi; Morimoto, Masaki; Inoue, Makoto

    The source Sgr B2 has been mapped with a single-dish resolution of ≡40arcsec at frequencies of 23 GHz and 43 GHz. An extended thermal component was found, and has been compared with that in lower frequency observations. The core region of Sgr B2 (containing the compact sources MD4 and MD5) was resolved at both 23 GHz and 43 GHz. The compact components MD4 and MD5 have complex thermal spectra which may indicate inhomogeneities within each compact core. A new source, G0.64-0.06, was found in the southern area of the extended thermal component. The 43-GHz map made with the Nobeyama 45-m telescope was compared with a 10.7-GHz map made with the Effelsberg 100-m telescope. This comparison suggests that there may be some nonthermal emission in the southern area of Sgr B2.

  17. The Australia Telescope 20 GHz Survey: The Source Catalogue

    CERN Document Server

    Murphy, Tara; Ekers, Ronald D; Massardi, Marcella; Hancock, Paul J; Mahony, Elizabeth; Ricci, Roberto; Burke-Spolaor, Sarah; Calabretta, Mark; Chhetri, Rajan; De Zotti, Gianfranco; Edwards, Philip G; Ekers, Jennifer A; Jackson, Carole A; Kesteven, Michael J; Lindley, Emma; Newton-McGee, Katherine; Phillips, Chris; Roberts, Paul; Sault, Robert J; Staveley-Smith, Lister; Subrahmanyan, Ravi; Walker, Mark A; Wilson, Warwick E

    2009-01-01

    We present the full source catalogue from the Australia Telescope 20 GHz (AT20G) Survey. The AT20G is a blind radio survey carried out at 20 GHz with the Australia Telescope Compact Array (ATCA) from 2004 to 2008, and covers the whole sky south of declination 0 deg. The AT20G source catalogue presented here is an order of magnitude larger than any previous catalogue of high-frequency radio sources, and includes 5890 sources above a 20 GHz flux-density limit of 40 mJy. All AT20G sources have total intensity and polarisation measured at 20 GHz, and most sources south of declination -15 deg also have near-simultaneous flux-density measurements at 5 and 8 GHz. A total of 1559 sources were detected in polarised total intensity at one or more of the three frequencies. We detect a small but significant population of non-thermal sources that are either undetected or have only weak detections in low-frequency catalogues. We introduce the term Ultra-Inverted Spectrum (UIS) to describe these radio sources, which have a ...

  18. Phase Closure at 691 GHz using the Submillimeter Array

    CERN Document Server

    Hunter, T R; Peck, A B; Christensen, R D; Blundell, R; Camacho, A; Patt, F; Sakamoto, K; Young, K H

    2007-01-01

    Phase closure at 682 GHz and 691 GHz was first achieved using three antennas of the Submillimeter Array (SMA) interferometer located on Mauna Kea, Hawaii. Initially, phase closure was demonstrated at 682.5 GHz on Sept. 19, 2002 using an artificial ground-based "beacon" signal. Subsequently, astronomical detections of both Saturn and Uranus were made at the frequency of the CO(6-5) transition (691.473 GHz) on all three baselines on Sept. 22, 2002. While the larger planets such as Saturn are heavily resolved even on these short baselines (25.2m, 25.2m and 16.4m), phase closure was achieved on Uranus and Callisto. This was the first successful experiment to obtain phase closure in this frequency band. The CO(6-5) line was also detected towards Orion BN/KL and other Galactic sources, as was the vibrationally-excited 658 GHz water maser line toward evolved stars. We present these historic detections, as well as the first arcsecond-scale images obtained in this frequency band.

  19. Low Noise Amplifier for 2.45 GHz Frequency Band at 0.18 μm CMOS Technology for IEEE Standard 802.11 b/g WLAN

    Directory of Open Access Journals (Sweden)

    Viranjay M. Srivastava

    2012-08-01

    Full Text Available This paper presents the design of low noise amplifier (LNA at 2.45 GHz and integrated at 0.18 µm RF CMOS process technology. This type of LNA at 2.45 GHz is use in the Bluetooth receiver. The proposed method is useful to optimize noise performance and power gain while maintaining good input and output matching. The amplifier is designed to be used as first stage of a receiver for wireless communication. The main aim of designer is to achieve low noise figure with improved gain with the help of CMOS technology by using single stage n-MOS amplifier. The simulation results show a forward gain of 14.0 dB, a noise-figure of 0.5 dB and stability factor is approximate unity, in which the circuit operates at 14.2 mA drain current with supply voltage of 3.5 V and biasing voltage of 1.5 V.

  20. Performance of the Caltech Submillimeter Observatory Dual-Color 180-720 GHz Balanced SIS Receivers

    CERN Document Server

    Kooi, J W; Monje, R; Kovacs, A; Rice, F; Yoshida, H; Force, B; Cooper, K; Miller, D; Gould, M; Lis, D; Bumble, B; LeDuc, R; Stern, J A; Phillips, T G

    2014-01-01

    We report on balanced SIS receivers covering the astronomical important 180-720 GHz submillimeter atmospheric window. To facilitate remote observations and automated spectral line surveys, fully synthesized local oscillators are employed. High-current-density Nb-AlN-Nb superconducting-insulating-superconducting (SIS) tunnel junctions are used as the mixing element. The measured double-sideband (DSB) 230 GHz receiver noise temperature, uncorrected for optics loss, ranges from 50K at 185 GHz, 33K at 246 GHz, to 51K at 280 GHz. In this frequency range the mixer has a DSB conversion gain of 0 +- 1.5 dB. The measured 460 GHz double-sideband receiver noise temperature, uncorrected for optics loss, is 32K at 400 GHz, 34K at 460 GHz, and 61K at 520 GHz. Similar to the 230 GHz balanced mixer, the DSB mixer conversion gain is 1 +- 1 dB. To help optimize performance, the mixer IF circuits and bias injection are entirely planar by design. Dual-frequency observation, by means of separating the incoming circular polarized ...

  1. A 200 GHz tripler using a single barrier varactor

    Science.gov (United States)

    Choudhury, Debabani; Frerking, Margaret A.; Batelaan, Paul D.

    1993-01-01

    The GaAs Schottky varactor diode is the nonlinear device most commonly used for submillimeter wave harmonic generation. Output power adequate to serve as a local oscillator source for SIS tunnel junctions has been demonstrated with whisker-contacted GaAs Schottky varactor multipliers in waveguide mounts up to about 800 GHz. In this paper, we present results for a tripler to 200 GHz using a new multiplier device, the single barrier varactor (SBV). This new varactor has potential advantages such as stronger nonlinearities or special symmetry, which make it attractive for submillimeter wave frequency multiplication. The performance of a tripler using a SBV over a output frequency range from 186 to 207 GHz has been measured in a crossed waveguide mount. The theoretical performance of the device has been calculated using large signal analysis. A comparison of theoretical and measured results and a discussion of various losses in the mount and the varactor have also been presented.

  2. A 200 GHz tripler using single barrier varactor

    Science.gov (United States)

    Choudhury, Debabani; Frerking, Margaret A.; Batelaan, Paul D.

    1992-01-01

    The GaAs Schottky varactor diode is the nonlinear device most commonly used for submillimeter wave harmonic generation. Output power adequate to serve as a local oscillator source for SIS tunnel junctions has been demonstrated with whisker-contacted GaAs Schottky varactor multipliers in waveguide mounts up to about 800 GHz. In this paper, we present results for a tripler to 200 GHz using a new multiplier device, the single barrier varactor (SBV). This new varactor has a potential advantages such as stronger nonlinearities or special symmetry, which make it attractive for submillimeter wave frequency multiplication. The performance of a tripler using a SBV over a output frequency range from 186 to 207 GHz has been measured in a crossed waveguide mount. The theoretical performance of the device has been calculated using large signal analysis. A comparison of theoretical and measured results and a discussion of various losses in the mount and the varactor have also been presented.

  3. The 20 GHz spacecraft FET solid state transmitter

    Science.gov (United States)

    1983-01-01

    The engineering development of a solid state transmitter amplifier operating in the 20 GHz frequency band using GaAs field effect transistors (FETs) was detailed. The major efforts include GaAs FET device development, single-ended amplifier stage, balanced amplifier stage, cascaded stage and radial combiner designs, and amplifier integration and test. A multistage GaAs FET amplifier capable of 8.2 W CW output over the 17.9 to 19.1 GHz frequency band was developed. The GaAs FET devices developed represent state of the art FET power device technology. Further device improvements are necessary to increase the bandwidth to 2.5 GHz, improve dc-to-RF efficiency, and increase power capability at the device level. Higher power devices will simplify the amplifier combining scheme, reducing the size and weight of the overall amplifier.

  4. Cold test of cylindrical open resonator for 42 GHz, 200 kW gyrotron

    Indian Academy of Sciences (India)

    Vivek Yadav; Sudeep Sharan; Hasina Khatun; Nitin Kumar; M K Alaria; B Jha; S C Deorani; A K Sinha; P K Jain

    2013-12-01

    This paper presents experimental results for cold testing of a gyrotron open resonator. Experiments were carried out to measure resonant frequency and their particular quality factor for TE mode at the frequency 42 GHz. The perturbation technique was used to determine the axial, radial and azimuthal electric field profile for identification of TE031 mode at operating frequency 42 GHz. The good agreement between experimental results and theoretical studies was found. The results verify the design and fabrication of the specific gyrotron cavity.

  5. 75GHz ECR等离子体%ECR Plasma with 75GHz Pumping

    Institute of Scientific and Technical Information of China (English)

    A.V.Vodopyanov; S.V.Golubev; I.V.Izotov; V.I.Khizhnyak; D.A.Mansfeld; V.A.Skalyga; V.G.Zorin

    2007-01-01

    A Simple Mirror Ion Source with 75GHz pumping(SMIS 75)has been created.The confinement system is a mirror trap with magnetic field in the plug up to 5T.variable length 15-20cm and mirror ratio 3-5.Plasma heating is performed by the microwave radiation of a gyrotron(frequency 75GHz,power up to 200kW,pulse duration up to 150μs).The first results on plasma creation,heating and confinement are presented.Gas discharge conditions and charge state distributions are investigated.The main features of the plasma are high density and short confinement time.Plasma is confined in the trap in quasi-gas-dynamic regime.This means very short rising time and very dense plasma flux.

  6. An integrated 500 GHz receiver with superconducting local oscillator

    NARCIS (Netherlands)

    Koshelets, VP; Shitov, SV; Filippenko, LV; Baryshev, AM; Luinge, W; Golstein, H; vandeStadt, H; Gao, [No Value; deGraauw, T

    1997-01-01

    An integrated quasioptical receiver consisting of a planar double - dipole antenna, SIS mixer and superconducting Flux-Flow Oscillator (FFO) with matching circuits has been designed, fabricated and tested in the frequency range 420-530 GHz. The integrated receiver is very suitable for space applicat

  7. First harmonic injection locking of 24-GHz-oscillators

    Directory of Open Access Journals (Sweden)

    M. R. Kühn

    2003-01-01

    Full Text Available An increasing number of applications is proposed for the 24 GHz ISM-band, like automotive radar systems and short-range communication links. These applications demand for oscillators providing moderate output power of a few mW and moderate frequency stability of about 0.5%. The maximum oscillation frequency of low-cost off-theshelf transistors is too low for stable operation of a fundamental 24GHz oscillator. Thus, we designed a 24 GHz first harmonic oscillator, where the power generated at the fundamental frequency (12 GHz is reflected resulting in effective generation of output power at the first harmonic. We measured a radiated power from an integrated planar antenna of more than 1mW. Though this oscillator provides superior frequency stability compared to fundamental oscillators, for some applications additional stabilization is required. As a low-cost measure, injection locking can be used to phase lock oscillators that provide sufficient stability in free running mode. Due to our harmonic oscillator concept injection locking has to be achieved at the first harmonic, since only the antenna is accessible for signal injection. We designed, fabricated and characterized a harmonic oscillator using the antenna as a port for injection locking. The locking range was measured versus various parameters. In addition, phase-noise improvement was investigated. A theoretical approach for the mechanism of first harmonic injection locking is presented.

  8. Microwave Radiometer - high frequency

    Data.gov (United States)

    Oak Ridge National Laboratory — The Microwave Radiometer-High Frequency (MWRHF) provides time-series measurements of brightness temperatures from two channels centered at 90 and 150 GHz. These two...

  9. Highly linear and transparent 3-18 GHz optical microwave link

    DEFF Research Database (Denmark)

    Nielsen, Torben Nørskov; Gliese, Ulrik Bo; Christensen, T.;

    1994-01-01

    A highly linear optical microwave link transmitter based on heterodyne phase-locked DFB lasers is presented. The transmitter is transparent for FM and PM input signals with carrier frequencies ranging from 3-18 GHz. Distortion-free transmission of a 7.6 GHz FM PAL video signal over 25 km of optical...

  10. Feasibility Study and Experimental Verification of Simplified Fiber-Supported 60-GHz Picocell Mobile Backhaul Links

    DEFF Research Database (Denmark)

    Lebedev, Alexander; Pang, Xiaodan; Vegas Olmos, Juan José

    2013-01-01

    We propose and experimentally demonstrate a fiber-wireless transmission system for optimized delivery of 60-GHz radio frequency (RF) signals through picocell mobile backhaul connections. We identify advantages of 60-GHz links for utilization in short-range mobile backhaul through feasibility...

  11. A robust optical phase modulated 60 GHz RoF WDM system

    DEFF Research Database (Denmark)

    Yu, Xianbin; Kozuch, Wojciech; Turkiewicz, Jaroslaw

    2010-01-01

    robust 4-channel WDM optical phase modulated 60GHz wireless fiber system is proposed and simulated. In this system, a Fabry-Perot (FP) frequency interleaver is designed to suppress optical carriers for 60GHz signal generation. The simulated results show that this phase modulated WDM system...

  12. Medium access control and network layer design for 60 GHz wireless personal area networks

    NARCIS (Netherlands)

    An, X.

    2010-01-01

    The unlicensed frequency band around 60 GHz is a very promising spectrum due to its potential to provide multiple gigabits per second based data rates for short range wireless communication. Hence, 60 GHz radio is an attractive candidate to enable ultra high rate Wireless Personal Area Networks (WPA

  13. THz photonic wireless links with 16-QAM modulation in the 375-450 GHz band

    DEFF Research Database (Denmark)

    Jia, Shi; Yu, Xianbin; Hu, Hao;

    2016-01-01

    forward error correction (HD-FEC) threshold of 3.8e-3 with 7% overhead. In addition, we also successfully demonstrate hybrid photonic wireless transmission of 40 Gbit/s 16-QAM signal at carrier frequencies of 400 GHz and 425 GHz over 30 km standard single mode fiber (SSMF) between the optical baseband...

  14. High sensitivity broadband 360GHz passive receiver for TeraSCREEN

    Science.gov (United States)

    Wang, Hui; Oldfield, Matthew; Maestrojuán, Itziar; Platt, Duncan; Brewster, Nick; Viegas, Colin; Alderman, Byron; Ellison, Brian N.

    2016-05-01

    TeraSCREEN is an EU FP7 Security project aimed at developing a combined active, with frequency channel centered at 360 GHz, and passive, with frequency channels centered at 94, 220 and 360 GHz, imaging system for border controls in airport and commercial ferry ports. The system will include automatic threat detection and classification and has been designed with a strong focus on the ethical, legal and practical aspects of operating in these environments and with the potential threats in mind. Furthermore, both the passive and active systems are based on array receivers with the active system consisting of a 16 element MIMO FMCW radar centered at 360 GHz with a bandwidth of 30 GHz utilizing a custom made direct digital synthesizer. The 16 element passive receiver system at 360 GHz uses commercial Gunn diode oscillators at 90 GHz followed by custom made 90 to 180 GHz frequency doublers supplying the local oscillator for 360 GHz sub-harmonic mixers. This paper describes the development of the passive antenna module, local oscillator chain, frequency mixers and detectors used in the passive receiver array of this system. The complete passive receiver chain is characterized in this paper.

  15. Experimental investigation of harmonic and subharmonic synchronization of 40 GHz mode-locked quantum-dash laser diodes.

    Science.gov (United States)

    Maldonado-Basilio, Ramón; Latkowski, Sylwester; Philippe, Severine; Landais, Pascal

    2011-05-01

    Synchronization of a 40 GHz quantum-dash mode-locked (ML) Fabry-Perot laser diode with optically injected pulse streams is experimentally studied. Injected signals consist of nonmodulated and modulated trains of 1.6 ps pulses at various repetition rates, ranging from 10 to 160 GHz and 10 to 160 Gbps, respectively. Subharmonic, fundamental, and harmonic synchronization of the ML laser allows retrieval of stable 40 GHz clock pulses featuring a width of 1.8 ps. Frequency components at 10 and 20 GHz do not create any amplitude modulation on the recovered 40 GHz clock pulses when injecting signals at 10 and 20 GHz/Gbps. In addition, external synchronization of the laser with pulse streams at 80 and 160 GHz/Gbps is sustained despite the absence of significant components at or below 40 GHz.

  16. Single dish performance of KVN 21-m radio telescopes:Simultaneous observations at 22 and 43 GHz

    CERN Document Server

    Lee, Sang-Sung; Oh, Chung Sik; Han, Seog-Tae; Je, Do-Heung; Kim, Kee-Tae; Wi, Seog-Oh; Cho, Se-Hyung; Sohn, Bong Won; Kim, Jaeheon; Lee, Jeewon; Oh, Se-Jin; Song, Min-Gyu; Kang, Jiman; Jung, Moon-Hee; Lee, Jeong Ae; Oh, Junghwan; Bae, Jae-Han; Yun, So-Young; Lee, Jung-Won; Kim, Bong Gyu; Chung, Hyunsoo; Roh, Duk-Gyoo; Lee, Chang Hoon; Kim, Hyun Goo; Kim, Hyo Ryoung; Yeom, Jae-Hwan; Kurayama, Tomoharu; Jung, Taehyun; Park, Pulun; Kim, Min Joong; Yoon, Dong-Hwan; Kim, Won-Ju

    2011-01-01

    We report simultaneous multi-frequency observing performance at 22 and 43 GHz of the 21-m shaped-Cassegrain radio telescopes of the Korean VLBI Network (KVN). KVN is the first millimeter-dedicated VLBI network in Korea having a maximum baseline length of 480 km. It currently operates at 22 and 43 GHz and planed to operate in four frequency bands, 22, 43, 86, and 129 GHz. The unique quasioptics of KVN enable simultaneous multi-frequency observations based on efficient beam filtering and accuarate antenna-beam alignment at 22 and 43 GHz. We found that the offset of the beams is within 20 degrees.

  17. Long-term variability of 3C 273 at 22 and 44 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Botti, L.C.L; Abraham, Z.

    1988-08-01

    Observations of 3C 273 at 22 and 44 GHz during the past 7 yr are presented. Between 1981 and 1984, the QSO was in a high-flux-density state at both frequencies, the intensity decreasing by a factor of 2 during 1985, reaching a minimum value in April 1986. The changes in the flux density were larger at 44 GHz and preceded the changes at 22 GHz. The variability in 1983 was identified with the millimeter and infrared outburst of February 1983, and the observed flux-density fluctuations were correlated with the appearance of the superluminal knots observed at 10.7 GHz with VLBI techniques. 46 references.

  18. Microwave ablation at 10.0 GHz achieves comparable ablation zones to 1.9 GHz in ex vivo bovine liver.

    Science.gov (United States)

    Luyen, Hung; Gao, Fuqiang; Hagness, Susan C; Behdad, Nader

    2014-06-01

    We demonstrate the feasibility of using high-frequency microwaves for tissue ablation by comparing the performance of a 10 GHz microwave ablation system with that of a 1.9 GHz system. Two sets of floating sleeve dipole antennas operating at these frequencies were designed and fabricated for use in ex vivo experiments with bovine livers. Combined electromagnetic and transient thermal simulations were conducted to analyze the performance of these antennas. Subsequently, a total of 16 ablation experiments (eight at 1.9 GHz and eight at 10.0 GHz) were conducted at a power level of 42 W for either 5 or 10 min. In all cases, the 1.9 and 10 GHz experiments resulted in comparable ablation zone dimensions. Temperature monitoring probes revealed faster heating rates in the immediate vicinity of the 10.0 GHz antenna compared to the 1.9 GHz antenna, along with a slightly delayed onset of heating farther from the 10 GHz antenna, suggesting that heat conduction plays a greater role at higher microwave frequencies in achieving a comparably sized ablation zone. The results obtained from these experiments agree very well with the combined electromagnetic/thermal simulation results. These simulations and experiments show that using lower frequency microwaves does not offer any significant advantages, in terms of the achievable ablation zones, over using higher frequency microwaves. Indeed, it is demonstrated that high-frequency microwave antennas may be used to create reasonably large ablation zones. Higher frequencies offer the advantage of smaller antenna size, which is expected to lead to less invasive interstitial devices and may possibly lead to the development of more compact multielement arrays with heating properties not available from single-element antennas.

  19. Developement of a 6 GHz subsystem for the RF control system of the S-DALINAC

    Energy Technology Data Exchange (ETDEWEB)

    Burandt, Christoph; Araz, Asim; Bonnes, Uwe; Eichhorn, Ralf; Enders, Joachim; Konrad, Martin; Steiner, Bastian; Weiland, Thomas [Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgartenstrasse 9, 64289 Darmstadt (Germany)

    2010-07-01

    A new source of polarized electrons is currently installed at the S-DALINAC. Due to spatial constraints at the existing installation, detailed planning and extensive simulation were done. Results from beam dynamics calculations show the necessity of further bunch compression. The new injector design therefore includes a harmonic prebunching system consisting of two normal conducting copper cavities operated at 3 GHz and 6 GHz respectively. Since the S-DALINAC is exclusively operated at 3 GHz new 6 GHz components have to be developed and need to be integrated into the RF control system. The basic idea of the existing analog control system and the future digital control system is the down conversion of RF signals to the base band. Therefore the low frequency part of each system can be used without adaptions while the RF module requires redevelopment. This talk covers the redesign of the existing 3 GHz RF module for 6 GHz and reports on results obtained with a prototype.

  20. High frequency (208 GHz) determination of the cubic spin Zeeman term for the U{sup 3+} ion in the dilute magnetic semiconductor crystals of Pb{sub 1−x}U{sub x}Te and Pb{sub 1−x}U{sub x}Se at 5 K by electron paramagnetic resonance

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Sushil K., E-mail: skmisra@alcor.concordia.ca; Michaels, Adam

    2015-03-15

    A high-frequency (208 GHz) Electron Paramagnetic Resonance (EPR) study on the U{sup 3+} ion (5f{sup 3}, {sup 4}I{sub 9/2}, S=3/2) embedded with 3% concentration in the dilute magnetic semiconductor crystals of PbTe and PbSe, each characterized by cubic symmetry, has been performed at ∼5 K, especially in view to determine the value of the Zeeman cubic spin term parameter u, and the site symmetry of the U{sup 3+} ion (radius 0.089 nm), substituting for the Pb{sup 2+} ion (radius 0.119 nm). The experimental spectra reveal the presence of only one set of EPR lines from U{sup 3+} ions in these host crystals, exhibiting cubic symmetry, whose magnetic axes are oriented along the crystal axes. The spin-Hamiltonian parameters are for both crystals: g=1.9811, u=-0.0257. - Highlights: • EPR studies of U{sup 3+} ion done at 208 GHz at 5 K embedded in PbTe and PbSe crystals. • Site symmetry at U{sup 3+} ion is determined to be cubic from EPR data. • Zeeman cubic spin term parameter u=-0.0257 determined for both crystals. • g=1.9811 Determined for both crystals.

  1. Ultra-wideband and 60 GHz communications for biomedical applications

    CERN Document Server

    Yuce, Mehmet R

    2013-01-01

    This book investigates the design of devices, systems, and circuits for medical applications using the two recently established frequency bands: ultra-wideband (3.1-10.6 GHz) and 60 GHz ISM band. These two bands provide the largest bandwidths available for communication technologies and present many attractive opportunities for medical applications. The applications of these bands in healthcare are wireless body area network (WBAN), medical imaging, biomedical sensing, wearable and implantable devices, fast medical device connectivity, video data transmission, and vital signs monitoring. The r

  2. 324GHz CMOS VCO Using Linear Superimposition Technique

    Science.gov (United States)

    Daquan, Huang; LaRocca, Tim R.; Samoska, Lorene A; Fung, Andy; Chang, Frank

    2007-01-01

    Terahertz (frequencies ranged from 300GHz to 3THz) imaging and spectroscopic systems have drawn increasing attention recently due to their unique capabilities in detecting and possibly analyzing concealed objects. The generation of terahertz signals is nonetheless nontrivial and traditionally accomplished by using either free-electron radiation, optical lasers, Gunn diodes or fundamental oscillation by using III-V based HBT/HEMT technology[1-3]... We have substantially extended the operation range of deep-scaled CMOS by using a linear superimposition method, in which we have realized a 324GHz VCO in 90nm digital CMOS with 4GHz tuning range under 1V supply voltage. This may also pave the way for ultra-high data rate wireless communications beyond that of IEEE 802.15.3c and reach data rates comparable to that of fiber optical communications, such as OC768 (40Gbps) and beyond.

  3. First results of the 2.45 GHz Oshima electron cyclotron resonance ion source

    Energy Technology Data Exchange (ETDEWEB)

    Asaji, T., E-mail: asaji@nc-toyama.ac.jp [National Institute of Technology, Toyama College, 13 Hongo, Toyama 939-8630 (Japan); Nakamura, T.; Furuse, M. [National Institute of Technology, Oshima College, 1091-1 Komatsu, Suouoshima, Oshima, Yamaguchi 742-2193 (Japan); Hitobo, T. [Tateyama Machine Co., Ltd., 30 Shimonoban, Toyama 930-1305 (Japan); Uchida, T. [Graduate School of Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350-8585 (Japan); Muramatsu, M. [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kato, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2016-02-15

    A new electron cyclotron resonance ion source has been constructed at Oshima College with a 2.45 GHz magnetron microwave source and permanent magnets employed as the main components. In addition, a solid-state power amplifier with a frequency range of 2.5–6.0 GHz was installed to study two-frequency plasma heating. Three solenoid coils were set up for adjusting the axial magnetic fields. Argon plasma generation and ion beam production have been conducted during the first year of operation. Ion current densities in the ECR plasma were measured using a biased disk. For 2.45 and 4.65 GHz two-frequency plasma heating, the ion density was approximately 1.5 times higher than that of 2.45 GHz single-frequency heating.

  4. Arbitrary waveform modulated pulse EPR at 200 GHz

    Science.gov (United States)

    Kaminker, Ilia; Barnes, Ryan; Han, Songi

    2017-06-01

    We report here on the implementation of arbitrary waveform generation (AWG) capabilities at ∼200 GHz into an Electron Paramagnetic Resonance (EPR) and Dynamic Nuclear Polarization (DNP) instrument platform operating at 7 T. This is achieved with the integration of a 1 GHz, 2 channel, digital to analog converter (DAC) board that enables the generation of coherent arbitrary waveforms at Ku-band frequencies with 1 ns resolution into an existing architecture of a solid state amplifier multiplier chain (AMC). This allows for the generation of arbitrary phase- and amplitude-modulated waveforms at 200 GHz with >150 mW power. We find that the non-linearity of the AMC poses significant difficulties in generating amplitude-modulated pulses at 200 GHz. We demonstrate that in the power-limited regime of ω1 10 MHz) spin manipulation in incoherent (inversion), as well as coherent (echo formation) experiments. Highlights include the improvement by one order of magnitude in inversion bandwidth compared to that of conventional rectangular pulses, as well as a factor of two in improvement in the refocused echo intensity at 200 GHz.

  5. A 2.3/3.3 GHz Dual Band Antenna Design for WiMax Applications

    Directory of Open Access Journals (Sweden)

    Adit Kurniawan

    2014-10-01

    Full Text Available A triangular-slot antenna with rectangular patch for 2.3/3.3 GHz WiMax applications has been implemented on DICLAD 527 substrate (relative permittivity εr = 2.5 with 1.524 mm of substrate thickness. A rectangular patch printed on one side of the substrate is fed by a 50 Ω microstrip line and acts as the frequency tuning stub, while the triangular slot is positioned on the opposite side of the substrate, center lined to the rectangular stub. From the measurement results based on VSWR = 2 or equal to the return loss of 9.53 dB, at the lower band of 2.3 GHz the resulting impedance bandwidth is 290 MHz (from 2.16 to 2.45 GHZ and at the upper band of 3.3 GHz is  370 MHz (from 3.31 to 3.68GHz, providing services for 2.3 GHz and 3.3 GHz frequency bands allocated for WiMax applications. The antenna gain measurement at 2.3 GHz frequency band is almost agrees with the simulation result of 3.2 dBi. While at 3.3 GHz the gain is approximately 4.4 dBi and continues to decrease with increasing frequency. The antenna gain measurement achieves maximum of 4.8 dBi (6 dBi from simulation at about 3 GHz. The simulation and measurement results are evaluated and discussed.

  6. GHz modulation detection using a streak camera: Suitability of streak cameras in the AWAKE experiment

    Science.gov (United States)

    Rieger, K.; Caldwell, A.; Reimann, O.; Muggli, P.

    2017-02-01

    Using frequency mixing, a modulated light pulse of ns duration is created. We show that, with a ps-resolution streak camera that is usually used for single short pulse measurements, we can detect via an FFT detection approach up to 450 GHz modulation in a pulse in a single measurement. This work is performed in the context of the AWAKE plasma wakefield experiment where modulation frequencies in the range of 80-280 GHz are expected.

  7. AIP GHz modulation detection using a streak camera: Suitability of streak cameras in the AWAKE experiment

    CERN Document Server

    Rieger, K; Reimann, O; Muggli, P

    2017-01-01

    Using frequency mixing, a modulated light pulse of ns duration is created. We show that, with a ps-resolution streak camera that is usually used for single short pulse measurements, we can detect via an FFT detection approach up to 450 GHz modulation in a pulse in a single measurement. This work is performed in the context of the AWAKE plasma wakefield experiment where modulation frequencies in the range of 80–280 GHz are expected.

  8. PM noise of a 40 GHz air-dielectric cavity oscillator

    OpenAIRE

    Hati, Archita; Nelson, Craig W.; Riddle, B.; Howe, David A.

    2014-01-01

    We describe the design of a low-phase-modulated (PM) noise, 40 GHz oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator to improve the PM noise of a commercial 10 GHz dielectric resonator oscillator (DRO) frequency multiplied by four. The main features of this design incorporate (1) unloaded cavity quality factor (Q) of 30,000, (2) high coupling coefficient, (3) large carrier suppression by use of interferometric signal processing, (4) large operati...

  9. Advanced system characterizes antennas to 65 GHz

    Science.gov (United States)

    Francis, Michael H.; Kremer, Douglas P.; Repjar, Andrew G.

    1990-03-01

    The antenna measurement service offered by the National Institute of Standards and Technology provides radiation-pattern, on-axis gain, and polarization measurements to 65 GHz using planar near-field and extrapolation techniques. It is pointed out that measurements of millimeter-wave antennas are both difficult and costly to make and that such measurements require low-noise, high-power signal sources and exceptionally stable and repeatable connections. The process of the three-antenna extrapolation technique and subsequent measurements of dual-port circularly polarized antennas and swept-frequency gain measurements are analyzed, and antenna standards are noted. Insertion-loss measurements and attenuator calibration are discussed, and measurement uncertainties and far-field patterns are analyzed.

  10. Integrated 60GHz RF beamforming in CMOS

    CERN Document Server

    Yu, Yikun; van Roermund, Arthur H M

    2011-01-01

    ""Integrated 60GHz RF Beamforming in CMOS"" describes new concepts and design techniques that can be used for 60GHz phased array systems. First, general trends and challenges in low-cost high data-rate 60GHz wireless system are studied, and the phased array technique is introduced to improve the system performance. Second, the system requirements of phase shifters are analyzed, and different phased array architectures are compared. Third, the design and implementation of 60GHz passive and active phase shifters in a CMOS technology are presented. Fourth, the integration of 60GHz phase shifters

  11. Searching for Inflationary B-modes: Can dust emission properties be extrapolated from 350 GHz to 150 GHz?

    CERN Document Server

    Tassis, Konstantinos

    2014-01-01

    Recent Planck results have shown that the path to isolating an inflationary B-mode signal in microwave polarization passes through understanding and modeling the interstellar dust polarized emission foreground, even in regions of the sky with the lowest level of dust emission. One of the most commonly used ways to remove the dust foreground is to extrapolate the polarized dust emission signal from frequencies where it dominates (e.g., 350 GHz) to frequencies commonly targeted by cosmic microwave background experiments (e.g., 150 GHz). We show, using a simple 2-cloud model, that if more than one cloud is present along the line-of-sight, with even mildly different temperature and dust column density, but severely misaligned magnetic field, then the 350 GHz polarized sky map is not predictive of that at 150 GHz. This problem is intrinsic to all microwave experiments and is due to information loss due to line-of-sight integration. However, it can be alleviated through interstellar medium tomography: a reconstruct...

  12. 37 GHz observations of a large sample of BL Lacertae objects

    CERN Document Server

    Nieppola, E; Lähteenmäki, A; Valtaoja, E; Hakala, T; Hovatta, T; Kotiranta, M; Nummila, S; Ojala, T; Parviainen, M; Ranta, M; Saloranta, P -M; Torniainen, I; Tröller, M; 10.1086/512609

    2009-01-01

    We present 37 GHz data obtained at Metsahovi Radio Observatory in 2001 December - 2005 April for a large sample of BL Lacertae objects. We also report the mean variability indices and radio spectral indices in frequency intervals 5 - 37 GHz and 37 - 90 GHz. Approximately 34 % of the sample was detected at 37 GHz, 136 BL Lacertae objects in all. A large majority of the detected sources were low-energy BL Lacs (LBLs). The variability index values of the sample were diverse, the mean fractional variability of the sample being \\Delta S_2 = 0.31. The spectral indices also varied widely, but the average radio spectrum of the sample sources is flat. Our observations show that many of the high-energy BL Lacs (HBL), which are usually considered radio-quiet, can at times be detected at 37 GHz.

  13. Biasable Subharmonic Membrane Mixer for 520 to 600 GHz

    Science.gov (United States)

    Schlecht, Erich; Siegel, Peter; Mehdi, Imran; Gill, John; Velebir, James; Peralta, Alejandro; Tsang, Raymond; Oswald, John; Dengler, Robert

    2009-01-01

    The figure shows a biasable subharmonic mixer designed to operate in the frequency range from 520 to 600 GHz. This mixer is a prototype of low-power mixers needed for development of wideband, high-resolution spectrometers for measuring spectra of molecules in the atmospheres of Earth, other planets, and comets in the frequency range of 400 to 700 GHz. Three considerations dictated the main features of the design: It is highly desirable to operate the spectrometers at or slightly below room temperature. This consideration is addressed by choosing Schottky diodes as the frequency-mixing circuit elements because of all mixer diodes, Schottky diodes are the best candidates for affording sufficient sensitivity at or slightly below room-temperature range. The short wavelengths in the intended operating-frequency range translate to stringent requirements for precision of fabrication and assembly of the circuits; these requirements are even more stringent for wide-bandwidth circuits. This consideration is addressed in two ways: (1) As much as possible of the mixer circuitry is fabricated in the form of a monolithic integrated circuit on a GaAs membrane, employing a modified version of a process used previously to fabricate a non-subharmonic mixer for a frequency of 2.5 THz and frequency multipliers for frequencies up to 2 THz. (2) The remainder of the circuitry is precision machined into a waveguide block that holds the GaAs integrated circuit.

  14. InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz

    Science.gov (United States)

    Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, William; Dang, Linh; Li, Danny; Cavus, Abdullah; To, Richard; Lai, Richard

    2009-01-01

    Two single-stage InP heterojunction bipolar transistor (HBT) amplifiers operate at 184 and 255 GHz, using Northrop Grumman Corporation s InP HBT MMIC (monolithic microwave integrated circuit) technology. At the time of this reporting, these are reported to be the highest HBT amplifiers ever created. The purpose of the amplifier design is to evaluate the technology capability for high-frequency designs and verify the model for future development work.

  15. High power 303 GHz gyrotron for CTS in LHD

    Science.gov (United States)

    Yamaguchi, Y.; Kasa, J.; Saito, T.; Tatematsu, Y.; Kotera, M.; Kubo, S.; Shimozuma, T.; Tanaka, K.; Nishiura, M.

    2015-10-01

    A high-power pulsed gyrotron is under development for 300 GHz-band collective Thomson scattering (CTS) diagnostics in the Large Helical Device (LHD). High-density plasmas in the LHD require a probe wave with power exceeding 100 kW in the sub-terahertz region to obtain sufficient signal intensity and large scattering angles. At the same time, the frequency bandwidth should be less than several tens of megahertz to protect the CTS receiver using a notch filter against stray radiations. Moreover, duty cycles of ~ 10% are desired for the time domain analysis of the CTS spectrum. At present, a 77 GHz gyrotron for electron cyclotron heating is used as a CTS wave source in the LHD. However, the use of such a low-frequency wave suffers from refraction, cutoff and absorption at the electron cyclotron resonance layer. Additionally, the signal detection is severely affected by background noise from electron cyclotron emission. To resolve those problems, high-power gyrotrons in the 300 GHz range have been developed. In this frequency range, avoiding mode competition is critical to realizing high-power and stable oscillation. A moderately over-moded cavity was investigated to isolate a desired mode from neighbouring modes. After successful tests with a prototype tube, the practical one was constructed with a cavity for TE22,2 operation mode, a triode electron gun forming intense laminar electron beams, and an internal mode convertor. We have experimentally confirmed single mode oscillation of the TE22,2 mode at the frequency of 303.3 GHz. The spectrum peak is sufficiently narrow. The output power of 290 kW has been obtained at the moment.

  16. VLBI observations of 3C273 at 22 GHz and 43 GHz ; 2, test of Synchrotron Self-Compton process

    CERN Document Server

    Mantovani, F; McHardy, I M; Valerio, C

    1999-01-01

    The VLBI observations at 22 GHz and 43 GHz of the quasar 3C273 obtained during a multi-frequency campaign in late 1992 in the radio, millimetre and X-ray bands allow us to derive the components' angular sizes, their peak fluxes and turnover frequencies. Lower limits to the Doppler factors have been derived by comparing the observed X-ray fluxes with those predicted by the Synchrotron Self-Compton model. Independent estimates of the Doppler factors were obtained through the assumption of the energy equipartition between the particles and the magnetic field. Of the five components used to model the first two milli-arcseconds of the jet, apart from the core, two components are in equipartition and the remaining two, at larger distances from the core, have large Doppler factors and are mainly responsible for the X-ray emission due to the Synchrotron Self-Compton process.

  17. The effect of BaTiO{sub 3} particle shape on complex permittivity of 0.98MgTiO{sub 3}–0.02BaTiO{sub 3} composite powders at GHz frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Tuhkala, M., E-mail: mtuhkala@ee.oulu.fi [Microelectronics and Materials Physics Laboratories, University of Oulu, P.O. Box 4500, FIN-90014 Oulu (Finland); Maček, M. [Advanced Materials Department, Jožef Stefan Institute, Jamova cesta 36, SI-1000 Ljubljana (Slovenia); Siponkoski, T.; Juuti, J.; Teirikangas, M. [Microelectronics and Materials Physics Laboratories, University of Oulu, P.O. Box 4500, FIN-90014 Oulu (Finland); Suvorov, D. [Advanced Materials Department, Jožef Stefan Institute, Jamova cesta 36, SI-1000 Ljubljana (Slovenia); Jantunen, H. [Microelectronics and Materials Physics Laboratories, University of Oulu, P.O. Box 4500, FIN-90014 Oulu (Finland)

    2016-04-15

    Highlights: • Elongated micrometre sized BaTiO{sub 3} particles had strong effect on permittivity. • Effect was significantly stronger compared to μm and nm sized spherical particles. • Properties could be tailored by varying the particle shapes of dielectric powders. • Could be utilized, e.g., in a production of electrical composites for RF applications. - Abstract: The effect of BaTiO{sub 3} particle shape on the properties of 0.98MgTiO{sub 3}–0.02BaTiO{sub 3} composite powders was characterized and analyzed using an indirectly coupled open-ended coaxial cavity resonator at gigahertz frequencies. Elongated micrometre sized BaTiO{sub 3} particles were found to have a significantly stronger effect on permittivity when compared to composite powders having micro and nano sized spherical BaTiO{sub 3} particles. Inclusion permittivities and dielectric loss tangents of composite powders increased from that of pure MgTiO{sub 3} powder, 13.3 and 4.6 × 10{sup −3}, up to 15.7 and 1.7 × 10{sup −2} with needle shaped BaTiO{sub 3} particles, respectively. The presented results give valuable information for tailoring the properties of dielectrics which can be utilized in the vast field of electronic component manufacturing.

  18. InP MMIC Chip Set for Power Sources Covering 80-170 GHz

    Science.gov (United States)

    Ngo, Catherine

    2001-01-01

    We will present a Monolithic Millimeter-wave Integrated Circuit (MMIC) chip set which provides high output-power sources for driving diode frequency multipliers into the terahertz range. The chip set was fabricated at HRL Laboratories using a 0.1-micrometer gate-length InAlAs/InGaAs/InP high electron mobility transistor (HEMT) process, and features transistors with an f(sub max) above 600 GHz. The HRL InP HEMT process has already demonstrated amplifiers in the 60-200 GHz range. In this paper, these high frequency HEMTs form the basis for power sources up to 170 GHz. A number of state-of-the-art InP HEMT MMICs will be presented. These include voltage-controlled and fixed-tuned oscillators, power amplifiers, and an active doubler. We will first discuss an 80 GHz voltage-controlled oscillator with 5 GHz of tunability and at least 17 mW of output power, as well as a 120 GHz oscillator providing 7 mW of output power. In addition, we will present results of a power amplifier which covers the full WRIO waveguide band (75-110 GHz), and provides 40-50 mW of output power. Furthermore, we will present an active doubler at 164 GHz providing 8% bandwidth, 3 mW of output power, and an unprecedented 2 dB of conversion loss for an InP HEMT MMIC at this frequency. Finally, we will demonstrate a power amplifier to cover 140-170 GHz with 15-25 mW of output power and 8 dB gain. These components can form a power source in the 155-165 GHz range by cascading the 80 GHz oscillator, W-band power amplifier, 164 GHz active doubler and final 140-170 GHz power amplifier for a stable, compact local oscillator subsystem, which could be used for atmospheric science or astrophysics radiometers.

  19. Experimental results of superimposing 9.9 GHz extraordinary mode microwaves on 2.45 GHz ECRIS plasma

    Energy Technology Data Exchange (ETDEWEB)

    Nishiokada, Takuya, E-mail: nishiokada@nf.eie.eng.osaka-u.ac.jp; Nagaya, Tomoki; Hagino, Shogo; Otsuka, Takuro; Sato, Fuminobu; Kato, Yushi [Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Muramatsu, Masayuki; Kitagawa, Atsushi [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-855 (Japan)

    2016-02-15

    Efficient production of multicharged ions has been investigated on the tandem-type ECRIS in Osaka University. According to the consideration of the accessibility conditions of microwaves to resonance and cutoff regions, it was suggested that the upper hybrid resonance (UHR) heating contributed to enhancement of ion beam intensity. In order to enhance multicharged ion beams efficiently, injecting higher frequency microwave with extraordinary (X-mode) toward UHR region has been tried. In this study, 2.45 GHz frequency microwaves are used for conventional ECR discharge, and 9.9 GHz frequency microwaves with X-mode are superimposed for UHR heating. The effects of additive microwave injection are investigated experimentally in terms of plasma parameters and electron energy distribution function (EEDF) measured by Langmuir probe and ion beam current. As the results show, it is confirmed that the electrons in the high energy region are affected by 9.9 GHz X-mode microwave injection from the detailed analysis of EEDF.

  20. Development of 1.3GHz high-Tc rf SQUID

    Institute of Scientific and Technical Information of China (English)

    Liu Xin-Yuan; Xie Fei-Xiang; Meng Shu-Chao; Dai Yuan-Dong; Li Zhuang-Zhi; Ma Ping; Yang Tao; Nie Rui-Juan; Wang Fu-Ren

    2004-01-01

    @@ A new high-Tc (HTc) rf SQUID working at around 1.3GHz has been developed to avoid electromagnetic interference such as growing mobile communication jamming. This new system works in a frequency range from 1.23 to 1.42GHz (centred at 1.3GHz), which is not occupied by commercial communication. The sensor used in the 1.3GHz rf SQUID is made of a HTc coplanar superconducting resonator and a large-area HTc superconducting film concentrator. We have achieved in the 1.3GHz HTc rf SQUID system a minimal flux noise of 2.5×10-5φ0/√Hz and a magnetic field sensitivity of 38fT/√Hz in white noise range, respectively. The effective area of the concentrator fabricated on a 15×15mm2 substrate is 1.35mm2. It is shown that the 1.3GHz rf SQUID system has a high field sensitivity. Design and implementation of 1.3GHz HTc rf SQUID offers a promising direction of rf SQUID development for higher working frequency ranges.

  1. The Australia Telescope 20GHz (AT20G) Survey: analysis of the extragalactic source sample

    CERN Document Server

    Massardi, Marcella; end_of_the_skype_highlighting, Tara Murphy begin_of_the_skype_highlighting end_of_the_skype_highlighting begin_of_the_skype_highlighting; Mahony, Elizabeth; Hancock, Paul J; Chhetri, Rajan; De Zotti, Gianfranco; Sadler, Elaine M; Burke-Spolaor, Sarah; Calabretta, Mark; Edwards, Philip G; Ekers, Jennifer A; Jackson, Carole A; Kesteven, Michael J; Newton-McGee, Katherine; Phillips, Chris; Ricci, Roberto; Roberts, Paul; Sault, Robert J; Staveley-Smith, Lister; Subrahmanyan, Ravi; Walker, Mark A; Wilson, Warwick E

    2010-01-01

    The Australia Telescope 20 GHz (AT20G) survey is a blind survey of the whole Southern sky at 20 GHz with follow-up observations at 4.8, 8.6, and 20 GHz carried out with the Australia Telescope Compact Array (ATCA). In this paper we present an analysis of radio spectral properties in total intensity and polarisation, sizes, optical identifications, and redshifts of the sample of the 5808 extragalactic sources in the survey catalogue of confirmed sources over the whole Southern sky excluding the strip at Galactic latitude |b|500mJy, to 60% for S<100mJy. There is also a clear spectral steepening at higher frequencies with the median spectral index decreasing from -0.16 between 4.8 and 8.6GHz to -0.28 between 8.6 and 20GHz. Simultaneous observations in polarisation are available for all the sources at all the frequencies. 768 sources have a good quality detection of polarised flux density at 20GHz; 467 of them were also detected in polarisation at 4.8 and/or at 8.6GHz so that it has been possible to compare th...

  2. A 60 GHz Planar Diplexer Based on Substrate Integrated Waveguide Technology

    Directory of Open Access Journals (Sweden)

    Nikolaos Athanasopoulos

    2013-01-01

    Full Text Available This paper presents a millimeter-wave, 60 GHz frequency band planar diplexer based on substrate integrated waveguide (SIW technology. Diplexer consists of a pair of 5th-order SIW bandpass channel filters with center frequencies at 59.8 GHz and 62.2 GHz providing 1.67% and 1.6% relative bandwidths, respectively. SIW-to-microstrip transitions at diplexer ports enable integration in a millimeter-wave transceiver front end. Measurements are in good agreement with electromagnetic simulation, reporting very good channel isolation, small return losses, and moderate insertion losses in the passbands. The proposed SIW planar diplexer is integrated into a millimeter-wave transceiver front end for 60 GHz point-to-point multigigabit wireless backhaul applications, providing high isolation between transmit and receive channels.

  3. Miniature Packaging Concept for LNAs in the 200-300 GHz Range

    Science.gov (United States)

    Samoska, Lorene; Fung, Andy; Varonen, Mikko; Lin, Robert; Peralta, Alejandro; Soria, Mary; Lee, Choonsup; Padmanabhan, Sharmila; Sarkozy, Stephen; Lai, Richard

    2016-01-01

    In this work, we describe new miniaturized low noise amplifier modules which we developed for incorporation in small-scale satellites or Cubesats, and which exhibit similar or better performance compared to previously reported LNAs in the literature. We have targeted the WR4 (170-260 GHz) and WR3 (220-325 GHz) waveguide bands for the module development. The modules include two different methods of E-plane probes which have been developed for low loss, and stability at high frequencies. MMIC LNAs were also developed for these frequency ranges and fabricated in Northrop Grumman Corporation's 35 nm InP HEMT technology, and we have experimentally verified that noise performance is lower than reported in prior work. The best results include a miniature LNA module with 550K noise at 224 GHz, and a wideband LNA module with 15 dB gain from 230-280 GHz.

  4. The 4.8 GHz LHC Schottky pick-up system

    Energy Technology Data Exchange (ETDEWEB)

    Caspers, Fritz; Jimenez, Jose Miguel; Jones, Rhodri Owain; Kroyer, Tom; Vuitton, Christophe; /CERN; Hamerla, Timothy W.; Jansson, Andreas; Misek, Joel; Pasquinelli, Ralph J.; Seifrid, Peter; Sun, Ding; /Fermilab

    2007-06-01

    The LHC Schottky observation system is based on traveling wave type high sensitivity pickup structures operating at 4.8 GHz. The choice of the structure and operating frequency is driven by the demanding LHC impedance requirements, where very low impedance is required below 2 GHz, and good sensitivity at the selected band at 4.8 GHz. A sophisticated filtering and triple down -mixing signal processing chain has been designed and implemented in order to achieve the specified 100 dB instantaneous dynamic range without range switching. Detailed design aspects for the complete systems and test results without beam are presented and discussed.

  5. A Cylindrical Dielectric Resonator Antenna-Coupled Sensor Configuration for 94 GHz Detection

    Directory of Open Access Journals (Sweden)

    M. Kamran Saleem

    2014-01-01

    Full Text Available A novel antenna-coupled sensor configuration for millimeter wave detection is presented. The antenna is based on two cylindrical dielectric resonators (CDRs excited by rectangular slots placed below the CDRs. The HEM11Δ mode resonating at 94 GHz is generated within the CDRs and a 3 GHz impedance bandwidth is achieved at center frequency of 94 GHz. The simulated antenna gain is 7.8 dB, with a radiation efficiency of about 40%.

  6. 24-71 GHz PCB Array for 5G ISM

    Science.gov (United States)

    Novak, Markus H.; Volakis, John L.; Miranda, Felix A.

    2017-01-01

    Millimeter-wave 5G mobile architectures need to consolidate disparate frequency bands into a single, multifunctional array. Existing arrays are either narrow-band, prohibitively expensive or cannot be scaled to these frequencies. In this paper, we present the first ultra-wideband millimeter wave array to operate across six 5G and ISM bands spanning 24-71 GHz. Importantly, the array is realized using low-cost PCB. The paper presents the design and optimized layout, and discusses fabrication and measurements.

  7. The faint source population at 15.7 GHz - I. The radio properties

    NARCIS (Netherlands)

    Whittam, I. H.; Riley, J. M.; Green, D. A.; Jarvis, M. J.; Prandoni, I.; Guglielmino, G.; Morganti, R.; Röttgering, H. J. A.; Garrett, M. A.

    2013-01-01

    We have studied a sample of 296 faint (>0.5 mJy) radio sources selected from an area of the Tenth Cambridge (10C) survey at 15.7 GHz in the Lockman Hole. By matching this catalogue to several lower frequency surveys (e.g. including a deep GMRT survey at 610 MHz, a WSRT survey at 1.4 GHz, NVSS, FIRST

  8. Developement and initial operation of a 6 GHz subsystem for the RF control system of the S-DALINAC

    Energy Technology Data Exchange (ETDEWEB)

    Burandt, Christoph; Bonnes, Uwe; Eichhorn, Ralf; Konrad, Martin; Nonn, Patrick; Enders, Joachim [Institut fuer Kernphysik, Technische Universitaet Darmstadt (Germany)

    2011-07-01

    During 2010 a source of polarized electrons has been installed at the S-DALINAC. Spatial constraints as well as limited cathode charge lifetime necessitate an efficient compression of the electron bunches before they enter the superconducting accelerating cavities. The new injector design therefore contains a harmonic prebunching system consisting of two cavities operated at 3 GHz and 6 GHz, respectively. While 3 GHz components are at hand, 6 GHz components had to be developed and integrated into the new RF control system. The basic idea of the new digital control system is the down conversion of the RF signals to the base band. Therefore the low frequency part of each system can be used without adaptions, while the RF module required redevelopment. This talk covers the redesign of the existing 3 GHz RF module for 6 GHz and first experiences from the commissioning of the new prebuncher system at the S-DALINAC.

  9. Aircraft microwave observations and simulations of deep convection from 18 to 183 GHz. I - Observations

    Science.gov (United States)

    Adler, Robert F.; Mack, Robert A.; Prasad, N.; Hakkarinen, Ida M.; Yeh, H.-Y. M.

    1990-01-01

    Aircraft passive microwave observations of deep atmospheric convection at frequencies between 18 and 183 GHz are presented in conjunction with visible and infrared satellite and aircraft observations and ground-based radar observations. Deep convective cores are indicated in the microwave data by negative brightness temperature, T/(B) deviations from the land background (270 K) to extreme T(B) values below 100 K at 37, 92, and 183 GHz and below 200 K at 18 GHz. These T(B) minima, due to scattering by ice held aloft by the intense updrafts, are well correlated with areas of high radar reflectivity. For this land background case, T(B) is inversely correlated with rain rate at all frequencies due to T(B)-ice-rain correlations. Mean Delta-T between vertically polarized and horizontally polarized radiance in precipitation areas is approximately 6 K at both 18 GHz and 37 GHz, indicating nonspherical precipitation-size ice particles with a preferred horizontal orientation. Convective cores not observed in the visible and infrared data are clearly defined in the microwave observations, and borders of convective rain areas are well defined using the high-frequency (90 GHz and greater) microwave observations.

  10. A 12 GHZ RF Power source for the CLIC study

    CERN Document Server

    Peauger, F; Curt, S; Doebert, S; McMonagle, G; Rossat, G; Schirm, KM; Syratchev, I; Timeo, L; Kuzikhov, S; Vikharev, AA; Haase, A; Sprehn, D; Jensen, A; Jongewaard, EN; Nantista, CD; Vlieks, A

    2010-01-01

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  11. LFI 30 and 44 GHz receivers Back-End Modules

    Energy Technology Data Exchange (ETDEWEB)

    Artal, E; Aja, B; Fuente, M L de la; Pascual, J P; Mediavilla, A [Dpt. Ingenieria de Comunicaciones, Universidad de Cantabria, Plaza de la Ciencia, 39005 Santander (Spain); Martinez-Gonzalez, E [Instituto de Fisica de Cantabria, CSIC-Universidad de Cantabria, Avda. de los Castros s/n, 39005 Santander (Spain); Pradell, L; Paco, P de [Departament de Teoria del Senyal i Comunicacions, Universitat Politecnica de Catalunya, Barcelona (Spain); Bara, M; Blanco, E; GarcIa, E [Mier Comunicaciones S.A. La Garriga, Barcelona (Spain); Davis, R; Kettle, D; Roddis, N; Wilkinson, A [Jodrell Bank Centre for Astrophysics, University of Manchester, Manchester (United Kingdom); Bersanelli, M; Mennella, A; Tomasi, M [Universita degli studi di Milano, Department of Physics Via Celoria 16, Milano (Italy); Butler, R C; Cuttaia, F, E-mail: artale@unican.e [INAF/IASF - Bologna Via P. Gobetti 101, 40129 Bologna (Italy)

    2009-12-15

    The 30 and 44 GHz Back End Modules (BEM) for the Planck Low Frequency Instrument are broadband receivers (20% relative bandwidth) working at room temperature. The signals coming from the Front End Module are amplified, band pass filtered and finally converted to DC by a detector diode. Each receiver has two identical branches following the differential scheme of the Planck radiometers. The BEM design is based on MMIC Low Noise Amplifiers using GaAs P-HEMT devices, microstrip filters and Schottky diode detectors. Their manufacturing development has included elegant breadboard prototypes and finally qualification and flight model units. Electrical, mechanical and environmental tests were carried out for the characterization and verification of the manufactured BEMs. A description of the 30 and 44 GHz Back End Modules of Planck-LFI radiometers is given, with details of the tests done to determine their electrical and environmental performances. The electrical performances of the 30 and 44 GHz Back End Modules: frequency response, effective bandwidth, equivalent noise temperature, 1/f noise and linearity are presented.

  12. A 12 GHz RF Power Source for the CLIC Study

    Energy Technology Data Exchange (ETDEWEB)

    Schirm, Karl; /CERN; Curt, Stephane; /CERN; Dobert, Steffen; /CERN; McMonagle, Gerard; /CERN; Rossat, Ghislain; /CERN; Syratchev, Igor; /CERN; Timeo, Luca; /CERN; Haase, Andrew /SLAC; Jensen, Aaron; /SLAC; Jongewaard, Erik; /SLAC; Nantista, Christopher; /SLAC; Sprehn, Daryl; /SLAC; Vlieks, Arnold; /SLAC; Hamdi, Abdallah; /Saclay; Peauger, Franck; /Saclay; Kuzikov, Sergey; /Nizhnii Novgorod, IAP; Vikharev, Alexandr; /Nizhnii Novgorod, IAP

    2012-07-03

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  13. A 7-8 GHz serrodyne modulator in SiGe for MIMO signal generation

    NARCIS (Netherlands)

    Withagen, Johan C.J.G.; Annema, A.J.; Nauta, B.; Vliet, van F.E.

    2014-01-01

    An 8-bit 360o sawtooth modulated phase shifter is used to apply very small frequency offsets to RF signals between 7 and 8 GHz. Offsets between 6 Hz and 10MHz can be obtained. Such frequency offsets can be used to generate orthogonal signals, which are required in e.g. MIMO applications. Each undesi

  14. A Deterministic and Random Propagation Study with the Design of an Open Path 320 GHz to 340 GHz Transmissometer

    Science.gov (United States)

    Scally, Lawrence J.

    This program was implemented by Lawrence J. Scally for a Ph.D. under the EECE department at the University of Colorado at Boulder with most funding provided by the U.S. Army. Professor Gasiewski is the advisor and guider for the entire program; he has a strong history decades ago in this type of program. This program is developing a more advanced than previous years transmissometer, called Terahertz Atmospheric and Ionospheric Propagation, Absorption and Scattering System (TAIPAS), on an open path between the University of Colorado EE building roof and the mesa on owned by National Institute of Standards and Technology (NIST); NIST has invested money, location and support for the program. Besides designing and building the transmissometer, that has never be accomplished at this level, the system also analyzes the atmospheric propagation of frequencies by scanning between 320 GHz and 340 GHz, which includes the peak absorption frequency at 325.1529 GHz due to water absorption. The processing and characterization of the deterministic and random propagation characteristics of the atmosphere in the real world was significantly started; this will be executed with varies aerosols for decades on the permanently mounted system that is accessible 24/7 via a network over the CU Virtual Private Network (VPN).

  15. SiGe Building Blocks for Microwave Frequency Synthesizers

    OpenAIRE

    Vaucher, Cicero S.; Apostolidou, M; Farrugia, Andrew; Praamsma, Louis

    2004-01-01

    Implementations of Ku- and Ka-band PLL building blocks in the Philips QUBiC4G SiGe technology are presented: a 10 GHz fully-integrated low-phase-noise differential Colpttis oscillator, a 25 GHz low-power adaptive prescaler, and a 18 GHz truly-modular fully-programmable frequency divider.

  16. Antennas for 20/30 GHz and beyond

    Science.gov (United States)

    Chen, C. Harry; Wong, William C.; Hamada, S. Jim

    1989-01-01

    Antennas of 20/30 GHz and higher frequency, due to the small wavelength, offer capabilities for many space applications. With the government-sponsored space programs (such as ACTS) in recent years, the industry has gone through the learning curve of designing and developing high-performance, multi-function antennas in this frequency range. Design and analysis tools (such as the computer modelling used in feedhorn design and reflector surface and thermal distortion analysis) are available. The components/devices (such as BFN's, weight modules, feedhorns and etc.) are space-qualified. The manufacturing procedures (such as reflector surface control) are refined to meet the stringent tolerance accompanying high frequencies. The integration and testing facilities (such as Near-Field range) also advance to facilitate precision assembling and performance verification. These capabilities, essential to the successful design and development of high-frequency spaceborne antennas, shall find more space applications (such as ESGP) than just communications.

  17. Freely designable optical frequency conversion in Raman-resonant four-wave-mixing process

    Science.gov (United States)

    Zheng, Jian; Katsuragawa, Masayuki

    2015-01-01

    Nonlinear optical processes are governed by the relative-phase relationships among the relevant electromagnetic fields in these processes. In this Report, we describe the physics of arbitrary manipulation of Raman-resonant four-wave-mixing process by artificial control of relative phases. As a typical example, we show freely designable optical-frequency conversions to extreme spectral regions, mid-infrared and vacuum-ultraviolet, with near-unity quantum efficiencies. Furthermore, we show that such optical-frequency conversions can be realized by using a surprisingly simple technology where transparent plates are placed in a nonlinear optical medium and their positions and thicknesses are adjusted precisely. In a numerical simulation assuming practically applicable parameters in detail, we demonstrate a single-frequency tunable laser that covers the whole vacuum-ultraviolet spectral range of 120 to 200 nm. PMID:25748023

  18. Exploring the faint source population at 15.7 GHz

    CERN Document Server

    Whittam, Imogen H; Green, David A; Jarvis, Matt J

    2016-01-01

    We discuss our current understanding of the nature of the faint, high-frequency radio sky. The Tenth Cambridge (10C) survey at 15.7 GHz is the deepest high-frequency radio survey to date, covering 12 square degrees to a completeness limit of 0.5 mJy, making it the ideal starting point from which to study this population. In this work we have matched the 10C survey to several lower-frequency radio catalogues and a wide range of multi-wavelength data (near- and far-infrared, optical and X-ray). We find a significant increase in the proportion of flat-spectrum sources at flux densities below 1 mJy - the median radio spectral index between 15.7 GHz and 610 MHz changes from 0.75 for flux densities greater than 1.5 mJy to 0.08 for flux densities less than 0.8 mJy. The multi-wavelength analysis shows that the vast majority (> 94 percent) of the 10C sources are radio galaxies; it is therefore likely that these faint, flat spectrum sources are a result of the cores of radio galaxies becoming dominant at high frequenci...

  19. 3.5 Year Monitoring of 225 GHz Opacity at the Summit of Greenland

    Science.gov (United States)

    Matsushita, Satoki; Asada, Keiichi; Martin-Cocher, Pierre L.; Chen, Ming-Tang; Ho, Paul T. P.; Inoue, Makoto; Koch, Patrick M.; Paine, Scott N.; Turner, David D.

    2017-02-01

    We present the 3.5 years monitoring results of 225 GHz opacity at the summit of the Greenland ice sheet (Greenland Summit Camp) at an altitude of 3200 m using a tipping radiometer. We chose this site as our submillimeter telescope (Greenland Telescope) site, because conditions are expected to have low submillimeter opacity and because its location offers favorable baselines to existing submillimeter telescopes for global-scale Very Long Baseline Interferometry. The site shows a clear seasonal variation with the average opacity lower by a factor of two during winter. The 25%, 50%, and 75% quartiles of the 225 GHz opacity during the winter months of November through April are 0.046, 0.060, and 0.080, respectively. For the winter quartiles of 25% and 50%, the Greenland site is about 10%-30% worse than the Atacama Large Millimeter/submillimeter Array (ALMA) or the South Pole sites. Estimated atmospheric transmission spectra in winter season are similar to the ALMA site at lower frequencies (\\lt 450 GHz), which are transparent enough to perform astronomical observations almost all of the winter time with opacities \\lt 0.5, but 10%-25% higher opacities at higher frequencies (\\gt 450 GHz) than those at the ALMA site. This is due to the lower altitude of the Greenland site and the resulting higher line wing opacity from pressure-broadened saturated water lines in addition to higher dry air continuum absorption at higher frequencies. Nevertheless, half of the winter time at the Greenland Summit Camp can be used for astronomical observations at frequencies between 450 GHz and 1000 GHz with opacities \\lt 1.2, and 10% of the time show \\gt 10 % transmittance in the THz (1035 GHz, 1350 GHz, and 1500 GHz) windows. Summer season is good for observations at frequencies lower than 380 GHz. One major advantage of the Greenland Summit Camp site in winter is that there is no diurnal variation due to the polar night condition, and therefore the durations of low-opacity conditions

  20. Faraday effect in magnetic fluids at a frequency 10 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Maiorov, M.M. E-mail: maiorov@tesla.sal.1v

    2002-11-01

    This work presents some results of observed Faraday effect in magnetic fluids in the centimetric region of the electromagnetic spectrum. The effect is observed when a transversal electric wave of mode H{sub 11} propagates in the circular waveguide with a magnetic fluid. The constant magnetic field was applied along the waveguide. Magnetic fluids with different concentrations of magnetite core nanoparticles suspended in tetradecane (C{sub 14}H{sub 30}) are used in the magnetic fields from 0 to 1500 Oe. A 160 deg. rotation of wave polarization is obtained for a 200 mm sample.

  1. Solar Emissions From GHz to Sub-THz Frequencies

    Science.gov (United States)

    2015-05-21

    sites. A 3 and 7 THz dual photometer system is being constructed to be flown in a long duration stratospheric balloon flight in Antarctica (summer 2013... telemetry modules for this application. SOLAR-T uses two Golay cell detectors preceded by low-pass filters made of rough surface primary mirrors and...observations are stored on board, a telemetry system will forward solar activity compact data to the ground station. The experiment is planned to fly on

  2. A Tripler to 220 GHz Using a Back-to-Back Barrier-N-N+ Varactor Diode

    Science.gov (United States)

    Choudhury, D.; Siegel, P.; Raisanen, A.; Martin, S.; Smith, R.

    1994-01-01

    The back-to-back barrier-N-N+ (bbBNN) varactor is a nonlinear device being developed for frequency multiplier applications above 100 GHz. Its symmetrical C-V characteristic, low series resistance and suitability to planarization make it ideal choice for high frequency, low power, odd harmonic generation. In this paper, the performance of a 220 GHz tripler using integrated planar bbBNN devices is presented.

  3. Design of High Gain and Broadband Antennas at 60 GHz for Underground Communications Systems

    Directory of Open Access Journals (Sweden)

    Yacouba Coulibaly

    2012-01-01

    Full Text Available A new broadband and high gain dielectric resonator antenna for millimeter wave is presented. The investigated antenna configuration consists of a periodic square ring frequency selective surfaces on a superstrate, an aperture-coupled scheme feed, an intermediate substrate, and a cylindrical dielectric resonator. This antenna is designed to cover the ISM frequency band at 60 GHz (57 GHz–64 GHz. It was numerically designed using CST microwave Studio simulation software package. Another prototype with a plain dielectric superstrate is also studied for comparison purposes. A bandwidth of 13.56% at the centered frequency of 61.34 GHz and a gain of 11 dB over the entire ISM band have been achieved. A maximum gain of 14.26 dB is obtained at 60 GHz. This is an enhancement of 9 dB compared to a single DRA. HFSS is used to validate our antenna designs. Good agreement between the results of the two softwares is obtained. With these performances, these antennas promise to be useful in the design of future wireless underground communication systems operating in the unlicensed 60 GHz frequency band.

  4. Digital-photonic synthesis of ultra-low noise tunable signals from RF to 100 GHz

    CERN Document Server

    Fortier, T M; Quinlan, F; Baynes, F N; Metcalf, A J; Hati, A; Ludlow, A; Hinkley, N; Shimizu, M; Ishibashi, T; Campbell, J C; Diddams, S A

    2015-01-01

    The demand for higher data rates and better synchronization in communication and navigation systems necessitates the development of new wideband and tunable sources with noise performance exceeding that provided by traditional oscillators and synthesizers. Precision synthesis is paramount for providing frequency references and timing in a broad range of applications including next-generation telecommunications, high precision measurement, and radar and sensing. Here we describe a digital-photonic synthesizer (DPS) based on optical frequency division that enables the generation of widely tunable signals from near DC to 100 GHz with a fractional frequency instability of 1 part in 10^15. The spectral purity of the DPS derived signals represents an improvement in close-to-carrier noise performance over the current state-of-the-art of nearly 7 orders of magnitude in the W-band (100 GHz), and up to 5 orders of magnitude in the X-band (10 GHz).

  5. 3.5-Year Monitoring of 225 GHz Opacity at the Summit of Greenland

    CERN Document Server

    Matsushita, Satoki; Martin-Cocher, Pierre L; Chen, Ming-Tang; Ho, Paul T P; Inoue, Makoto; Koch, Patrick M; Paine, Scott N; Turner, David D

    2016-01-01

    We present the 3.5-yr monitoring results of 225 GHz opacity at the summit of the Greenland ice sheet (Greenland Summit Camp) at an altitude of 3200 m using a tipping radiometer. We chose this site as our submillimeter telescope (Greenland Telescope; GLT) site, because its location offers favorable baselines to existing submillimeter telescopes for global-scale VLBI. The site shows a clear seasonal variation with the average opacity lower by a factor of two during winter. For the winter quartiles of 25% and 50%, the Greenland site is about 10%-30% worse than the ALMA or the South Pole sites. Estimated atmospheric transmission spectra in winter season are similar to the ALMA site at lower frequencies (450 GHz) than those at the ALMA site. This is due to the lower altitude of the Greenland site. Nevertheless, half of the winter time at the Greenland site can be used for astronomical observations at frequencies between 450 GHz and 1000 GHz with opacities 10% transmittance in the THz (1035 GHz, 1350 GHz, and 1500 ...

  6. Continuum observation of sagittarius B2 at 23 and 43 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Akabane, Kenji; Sofue, Yoshiaki; Hirabayashi, Hisashi; Morimoto, Masaki; Inoue, Makoto; Downes, D.

    1988-01-01

    The source Sgr B2 has been mapped with a single-dish resolution of approx.40 sec. at frequencies of 23 GHz and 43 GHz (lambda = 1.3 cm and 6.9 mm respectively). An extended thermal component was found, and has been compared with that in lower frequency observations. The core region of Sgr B2 (containing the compact sources MD4 and MD5) was resolved at both 23 GHz and 43 GHz. The compact components MD4 and MD5 have complex thermal spectra which may indicate inhomogeneities within each compact core. A new source, G0.64-0.06, was found in the southern area of the extended thermal component. The 43-GHz map made with the Nobeyama 45-m telescope was also convolved to an angular resolution of 1.3 min, for comparison with a 10.7-GHz map made with the Effelsberg 100-m telescope. This comparison suggests that there may be some nonthermal emission in the southern area of Sgr B2.

  7. 47 CFR 80.1077 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 80.1077 Section 80.1077... Frequencies. The following table describes the frequencies used in the Global Maritime Distress and Safety... frequency 9 GHz radar transponders 9200-9500 MHz. 1 Frequency 156.525 MHz can be used for...

  8. The 18/30 GHz fixed communications system service demand assessment. Volume 2: Main text

    Science.gov (United States)

    Gabriszeski, T.; Reiner, P.; Rogers, J.; Terbo, W.

    1979-01-01

    The total demand for communications services, and satellite transmission services at the 4/6 GHz, 12/14 GHz, and 18/30 GHz frequencies is assessed. The services are voice, video, and data services. Traffic demand, by service, is distributed by geographical regions, population density, and distance between serving points. Further distribution of traffic is made among four major end user groups: business, government, institutions and private individuals. A traffic demand analysis is performed on a typical metropolitan city to examine service distribution trends. The projected cost of C and Ku band satellite systems are compared on an individual service basis to projected terrestrial rates. Separation of traffic between transmission systems, including 18/30 GHz systems, is based on cost, user, and technical considerations.

  9. Feedhorn-coupled TES polarimeter camera modules at 150 GHz for CMB polarization measurements with SPTpol

    CERN Document Server

    Henning, J W; Aird, K A; Austermann, J E; Beall, J A; Becker, D; Benson, B A; Bleem, L E; Britton, J; Carlstrom, J E; Chang, C L; Cho, H -M; Crawford, T M; Crites, A T; Datesman, A; de Haan, T; Dobbs, M A; Everett, W; Ewall-Wice, A; George, E M; Halverson, N W; Harrington, N; Hilton, G C; Holzapfel, W L; Hubmayr, J; Irwin, K D; Karfunkle, M; Keisler, R; Kennedy, J; Lee, A T; Leitch, E; Li, D; Lueker, M; Marrone, D P; McMahon, J J; Mehl, J; Meyer, S S; Montgomery, J; Montroy, T E; Nagy, J; Natoli, T; Nibarger, J P; Niemack, M D; Novosad, V; Padin, S; Pryke, C; Reichardt, C L; Ruhl, J E; Saliwanchik, B R; Sayre, J T; Schaffer, K K; Shirokoff, E; Story, K; Tucker, C; Vanderlinde, K; Vieira, J D; Wang, G; Williamson, R; Yefremenko, V; Yoon, K W; Young, E; 10.1117/12.927172

    2012-01-01

    The SPTpol camera is a dichroic polarimetric receiver at 90 and 150 GHz. Deployed in January 2012 on the South Pole Telescope (SPT), SPTpol is looking for faint polarization signals in the Cosmic Microwave Background (CMB). The camera consists of 180 individual Transition Edge Sensor (TES) polarimeters at 90 GHz and seven 84-polarimeter camera modules (a total of 588 polarimeters) at 150 GHz. We present the design, dark characterization, and in-lab optical properties of the 150 GHz camera modules. The modules consist of photolithographed arrays of TES polarimeters coupled to silicon platelet arrays of corrugated feedhorns, both of which are fabricated at NIST-Boulder. In addition to mounting hardware and RF shielding, each module also contains a set of passive readout electronics for digital frequency-domain multiplexing. A single module, therefore, is fully functional as a miniature focal plane and can be tested independently. Across the modules tested before deployment, the detectors average a critical temp...

  10. VizieR Online Data Catalog: 22GHz image of 3C 273 (Bruni+, 2017)

    Science.gov (United States)

    Bruni, G.; Gomez, J. L.; Casadio, C.; Lobanov, A.; Kovalev, Y. Y.; Sokolovsky, K. V.; Lisakov, M. M.; Bach, U.; Marscher, A.; Jorstad, S.; Anderson, J. M.; Krichbaum, T. P.; Savolainen, T.; Vega-Garcia, L.; Fuentes, A.; Zensus, J. A.; Alberdi, A.; Lee, S.-S.; Lu, R.-S.; Perez-Torres, M.; Ros, E.

    2017-07-01

    A global ground array of 22 antennas was used to perform observations, including VLBA (Sc, Hn, Nl, Fd, La, Kp, Pt, Ov, Br, Mk), EVN (Hh, Mc, Nt, Tr, Jb, Ef, Ys), Long Baseline Array (-LBA- At, Mp, Ho, Cd), and two Kvazar antennas (Sv, Zc), plus Kalyazin (managed by ASC, Russia), and Green Bank (NRAO, USA). The observations took place on January 18-19, 2014, for a total of 16.8 hours, and at three different frequencies: 15GHz, 22GHz, and 43GHz. RA was involved only for the 22GHz part, while for the other bands only the VLBA was used. Both the Green Bank and Pushchino tracking station took part in the experiment. A RA-compatible total bandwidth of 32MHz, split into two 16-MHz IFs, was used. RA was scheduled to observe three consecutive 9.5 minute scans every 1.25 hours, to allow for antenna cooling. (2 data files).

  11. 160 Gbit/s photonics wireless transmission in the 300-500 GHz band

    Science.gov (United States)

    Yu, X.; Jia, S.; Hu, H.; Galili, M.; Morioka, T.; Jepsen, P. U.; Oxenløwe, L. K.

    2016-11-01

    To accommodate the ever increasing wireless traffic in the access networks, considerable efforts have been recently invested in developing photonics-assisted wireless communication systems with very high data rates. Superior to photonic millimeter-wave systems, terahertz (THz) band (300 GHz-10 THz) provides a much larger bandwidth and thus promises an extremely high capacity. However, the capacity potential of THz wireless systems has by no means been achieved yet. Here, we successfully demonstrate 160 Gbit/s wireless transmission by using a single THz emitter and modulating 25 GHz spaced 8 channels (20 Gbps per channel) in the 300-500 GHz band, which is the highest bitrate in the frequency band above 300 GHz, to the best of our knowledge.

  12. Planck 2013 results. VI. High Frequency Instrument data processing

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Armitage-Caplan, C.

    2013-01-01

    We describe the processing of the 531 billion raw data samples from the High Frequency Instrument (HFI), which we performed to produce six temperature maps from the first 473 days of Planck-HFI survey data. These maps provide an accurate rendition of the sky emission at 100, 143,217, 353, 545......, these two high frequency channels are calibrated to within 5% and the 353 GHz channel to the percent level. The 100 and217 GHz channels, which together with the 143 GHz channel determine the high-multipole part of the CMB power spectrum (50 ..., and 857 GHz with an angular resolution ranging from 9.07 to 4.06. The detector noise per (effective) beam solid angle is respectively,10, 6 , 12, and 39 µK in the four lowest HFI frequency channels (100-353 GHz) and 13 and 14 kJy sr-1 in the 545 and 857 GHz channels. Relativeto the 143 GHz channel...

  13. Distilling perfect GHZ states from two copies of non-GHZ-diagonal mixed states

    Science.gov (United States)

    Wang, Xin-Wen; Tang, Shi-Qing; Yuan, Ji-Bing; Zhang, Deng-Yu

    2017-06-01

    It has been shown that a nearly pure Greenberger-Horne-Zeilinger (GHZ) state could be distilled from a large (even infinite) number of GHZ-diagonal states that can be obtained by depolarizing general multipartite mixed states (non-GHZ-diagonal states) through sequences of (probabilistic) local operations and classical communications. We here demonstrate that perfect GHZ states can be extracted, with certain probabilities, from two copies of non-GHZ-diagonal mixed states when some conditions are satisfied. This result implies that it is not necessary to depolarize these entangled mixed states to the GHZ-diagonal type, and that they are better than GHZ-diagonal states for distillation of pure GHZ states. We find a wide class of multipartite entangled mixed states that fulfill the requirements. Moreover, we display that the obtained result can be applied to practical noisy environments, e.g., amplitude-damping channels. Our findings provide an important complementarity to conventional GHZ-state distillation protocols (designed for GHZ-diagonal states) in theory, as well as having practical applications.

  14. A wideband 240 GHz receiver for the submillimeter array

    Science.gov (United States)

    Tong, C.-Y. Edward; Grimes, Paul K.; Leiker, Patrick S.; Zeng, Lingzhen; Lu, Wei-Chun; Chen, Tse-Jun; Han, Chih-Chiang; Wang, Ming-Jye

    2016-07-01

    We report on the design of a 240 GHz double-side-band receiver for the Submillimeter Array (SMA). The heart of this receiver is a 3-junction series connected SIS mixer, which allows it to provide intermediate frequency (IF) output up to more than 12 GHz. We have custom built a low noise Amplifier-Multiplier Chain for use as the receiver's Local Oscillator module, which is tunable from 210 to 270 GHz. The receiver has demonstrated low noise performance in laboratory. 7 out of the 8 SMA antennas are now equipped with this receiver. The receiver has already participated in Event Horizon Telescope observations in April 2016, working with the SMA-200 receiver to provide dual polarization coverage for the EHT Hawaii Station. This receiver has enabled the SMA to provide 32 Gbit per second data stream to the EHT observations. We are currently trying to improve the on-sky beam co-alignment of this receiver with respect to other SMA receivers.

  15. A 12 GHz low-jitter LC-VCO PLL in 130 nm CMOS

    Science.gov (United States)

    You, Y.; Chen, J.; Feng, Y.; Tang, Y.; Huang, D.; Rui, W.; Gong, D.; Liu, T.; Ye, J.

    2015-03-01

    We present a wideband low-jitter LC-VCO phase-locked loop in 130 nm CMOS technology for high speed serial link applications. The PLL covers a 5.6 GHz to 13.4 GHz frequency range by using two LC-VCO cores with an RMS jitter of 370 fs. The single event effects testing is performed with a neutron beam at Los Alamos National Laboratory and no frequency disturbance is found over the test period. The PLL consumes 50.88 mW of power under a 1.2 V power supply.

  16. PM noise of a 40 GHz air-dielectric cavity oscillator

    CERN Document Server

    Hati, Archita; Riddle, B; Howe, David A

    2014-01-01

    We describe the design of a low-phase-modulated (PM) noise, 40 GHz oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator to improve the PM noise of a commercial 10 GHz dielectric resonator oscillator (DRO) frequency multiplied by four. The main features of this design incorporate (1) unloaded cavity quality factor (Q) of 30,000, (2) high coupling coefficient, (3) large carrier suppression by use of interferometric signal processing, (4) large operating signal power of approximately 1 watt (W), and (5) relatively small size. In addition, we report the PM noise of several Ka-band components.

  17. High-Capacity 60 GHz and 75–110 GHz Band Links Employing All-Optical OFDM Generation and Digital Coherent Detection

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio; Zibar, Darko; Sambaraju, Rakesh

    2012-01-01

    The performance of wireless signal generation and detection at millimeter-wave frequencies using baseband optical means is analyzed and experimentally demonstrated. Multigigabit wireless signal generation is achieved based on all-optical orthogonal frequency division multiplexing (OFDM) and photo......The performance of wireless signal generation and detection at millimeter-wave frequencies using baseband optical means is analyzed and experimentally demonstrated. Multigigabit wireless signal generation is achieved based on all-optical orthogonal frequency division multiplexing (OFDM...... scalability and bit-rate transparency of our proposed approach, we experimentally demonstrated generation and detection in the 60 GHz and 75–110 GHz band of an all-optical OFDM quadrature phase shift keying, with two and three subcarriers, for a total bit rate over 20 Gb/ s....

  18. Period-Doubling in 10 GHz Gain-Switched DFB Laser Diode

    Institute of Scientific and Technical Information of China (English)

    WU Jian; QIU Ji-Fang; LIN Jin-Tong

    2007-01-01

    The distinct period doubling behaviour in a 10 GHz gain-switched (GS) DFB laser is experimentally investigatedin frequency domain and in time domain. The period doubling occurs as the frequency of the rf driving signal is close to or higher than the -3 dB cutoff frequency of the DFB laser diode, and the amplitude of the rf driving signal required to achieve period doubling increases linearly with the increasing bias current of the laser diode.

  19. 14 GHz visible supercontinuum generation: calibration sources for astronomical spectrographs.

    Science.gov (United States)

    Stark, S P; Steinmetz, T; Probst, R A; Hundertmark, H; Wilken, T; Hänsch, T W; Udem, Th; Russell, P St J; Holzwarth, R

    2011-08-15

    We report the use of a specially designed tapered photonic crystal fiber to produce a broadband optical spectrum covering the visible spectral range. The pump source is a frequency doubled Yb fiber laser operating at a repetition rate of 14 GHz and emitting sub-5 pJ pulses. We experimentally determine the optimum core diameter and achieve a 235 nm broad spectrum. Numerical simulations are used to identify the underlying mechanisms and explain spectral features. The high repetition rate makes this system a promising candidate for precision calibration of astronomical spectrographs.

  20. First demonstration of a vehicle mounted 250GHz real time passive imager

    Science.gov (United States)

    Mann, Chris

    2009-05-01

    This paper describes the design and performance of a ruggedized passive Terahertz imager, the frequency of operation is a 40GHz band centred around 250GHz. This system has been specifically targeted at vehicle mounted operation, outdoors in extreme environments. The unit incorporates temperature stabilization along with an anti-vibration chassis and is sealed to allow it to be used in a dusty environment. Within the system, a 250GHz heterodyne detector array is mated with optics and scanner to allow real time imaging out to 100 meters. First applications are envisaged to be stand-off, person borne IED detection to 30 meters but the unique properties in this frequency band present other potential uses such as seeing through smoke and fog. The possibility for use as a landing aid is discussed. A detailed description of the system design and video examples of typical imaging output will be presented.

  1. A 23 GHz low power VCO in SiGe BiCMOS technology

    Institute of Scientific and Technical Information of China (English)

    Huang Yinkun; Wu Danyu; Zhou Lei; Jiang Fan; Wu Jin; Jin Zhi

    2013-01-01

    A 23 GHz voltage controlled oscillator (VCO) with very low power consumption is presented.This paper presents the design and measurement of an integrated millimeter wave VCO.This VCO employs an on-chip inductor and MOS varactor to form a high Q resonator.The VCO RFIC was implemented in a 0.18 μm 120 GHz ft SiGe hetero-junction bipolar transistor (HBT) BiCMOS technology.The VCO oscillation frequency is around 23 GHz,targeting at the ultra wideband (UWB) and short range radar applications.The core of the VCO circuit consumes 1 mA current from a 2.5 V power supply and the VCO phase noise was measured at around-94 dBc/Hz at a 1 MHz frequency offset.The FOM of the VCO is-177 dBc/Hz.

  2. An Accurate Flux Density Scale from 50 MHz to 50 GHz

    CERN Document Server

    Perley, R A

    2016-01-01

    The flux density scale of Perley and Butler (2013) is extended downwards to ~50 MHz by utilizing recent observations with the Karl G. Jansky Very Large Array (VLA) of 20 sources between 220 MHz and 48.1 GHz, and legacy VLA observations at 73.8 MHz. The derived spectral flux densities are placed on an absolute scale by utilizing the Baars et al. (1977) values of Cygnus A (3C405) for frequencies below 2 GHz, and the Mars-based polynomials for 3C286, 3C295, and 3C196 from Perley and Butler (2013) above 2 GHz. Polynomial expressions are presented for all 20 sources, with accuracy limited by the primary standards to 3 -- 5% over the entire frequency range. Corrections to the scales proposed by Perley and Butler (2013) and by Scaife and Heald (2012) are given.

  3. Research of sine waveguide slow-wave structure for a 220-GHz backward wave oscillator

    Institute of Scientific and Technical Information of China (English)

    Xu Xiong; Wei Yan-Yu; Shen Fei; Huang Min-Zhi; Tang Tao; Duan Zhao-Yun; Gong Yu-Bin

    2012-01-01

    A watt-class backward wave oscillator is proposed,using the concise sine waveguide slow-wave structure combined with a pencil electron beam to operate at 220 GHz.Firstly,the dispersion curve of the sine waveguide is calculated,then,the oscillation frequency and operating voltage of the device are predicted and the circuit transmission loss is calculated.Finally,the particle-in-cell simulation method is used to forecast its radiation performance.The results show that this novel backward wave oscillator can produce over 1-W continuous wave power output in a frequency range from 210 GHz to 230 GHz.Therefore,it will be considered as a very promising high-power millimeter-wave to terahertz-wave radiation source.

  4. The 492 GHz emission of Sgr A* constrained by ALMA

    Science.gov (United States)

    Liu, Hauyu Baobab; Wright, Melvyn C. H.; Zhao, Jun-Hui; Mills, Elisabeth A. C.; Requena-Torres, Miguel A.; Matsushita, Satoki; Martín, Sergio; Ott, Jürgen; Morris, Mark R.; Longmore, Steven N.; Brinkerink, Christiaan D.; Falcke, Heino

    2016-09-01

    Aims: Our aim is to characterize the polarized continuum emission properties including intensity, polarization position angle, and polarization percentage of Sgr A* at ~492 GHz. This frequency, well into the submillimeter bump where the emission is supposed to become optically thin, allows us to see down to the event horizon. Hence the reported observations contain potentially vital information on black hole properties. We have compared our measurements with previous, lower frequency observations, which provides information in the time domain. Methods: We report continuum emission properties of Sgr A* at ~492 GHz, based on Atacama Large Millimeter Array (ALMA) observations. We measured flux densities of Sgr A* from the central fields of our ALMA mosaic observations. We used calibration observations of the likely unpolarized continuum emission of Titan and the observations of Ci line emission, to gauge the degree of spurious polarization. Results: The flux density of 3.6 ± 0.72 Jy which we measured during our run is consistent with extrapolations from previous, lower frequency observations. We found that the continuum emission of Sgr A* at ~492 GHz shows large amplitude differences between the XX and the YY correlations. The observed intensity ratio between the XX and YY correlations as a function of parallactic angle can be explained by a constant polarization position angle of ~158°± 3°. The fitted polarization percentage of Sgr A* during our observational period is 14% ± 1.2%. The calibrator quasar J1744-3116 we observed on the same night can be fitted to Stokes I = 252 mJy, with 7.9% ± 0.9% polarization at position angle PA = 14°± 4.2°. Conclusions: The observed polarization percentage and polarization position angle in the present work appear consistent with those expected from longer wavelength observations in the period of 1999-2005. In particular, the polarization position angle at 492 GHz expected from the previously fitted 167°± 7° intrinsic

  5. Automation of measurement frequency SVCh kolebany

    Directory of Open Access Journals (Sweden)

    A. A. Parfenov

    1987-12-01

    Full Text Available The functional diagram of the frequency meter, comprising a microprocessor controller and commercially available devices. An algorithm for calculating the frequency of the microprocessor used in determining the frequency SVChgeneratora. In the range of 52-79 GHz frequency provides direct reading with an absolute error of less than 2 MHz.

  6. Realization of GHZ States and the GHZ Test via Cavity QED

    CERN Document Server

    Guerra, E S

    2004-01-01

    In this article we discuss the realization of atomic GHZ states involving three-level atoms and we show explicitly how to use this state to perform the GHZ test in which it is possible to decide between local realism theories and quantum mechanics. The experimental realizations proposed makes use of the interaction of Rydberg atoms with a cavity prepared in a coherent state.

  7. Antenne Design for 24 GHz and 60 GHz Emerging Microwave Applications

    NARCIS (Netherlands)

    Jansen, F.; Dolmans, W.M.C.

    2006-01-01

    In this project integrated antennas on a LAMP3 substrate for automotive radar systems at 24 GHz and wireless networks at 60 GHz have been designed. The most severe requirements on the antennas were the large bandwidth, which can not be met with conventional patch antennas. A tapered slot antenna and

  8. Antenne Design for 24 GHz and 60 GHz Emerging Microwave Applications

    NARCIS (Netherlands)

    Jansen, F.; Dolmans, W.M.C.

    2006-01-01

    In this project integrated antennas on a LAMP3 substrate for automotive radar systems at 24 GHz and wireless networks at 60 GHz have been designed. The most severe requirements on the antennas were the large bandwidth, which can not be met with conventional patch antennas. A tapered slot antenna and

  9. Low-Noise MMIC Amplifiers for 120 to 180 GHz

    Science.gov (United States)

    Pukala, David; Samoska, Lorene; Peralta, Alejandro; Bayuk, Brian; Grundbacher, Ron; Oliver, Patricia; Cavus, Abdullah; Liu, Po-Hsin

    2009-01-01

    Three-stage monolithic millimeter-wave integrated-circuit (MMIC) amplifiers capable of providing useful amounts of gain over the frequency range from 120 to 180 GHz have been developed as prototype low-noise amplifiers (LNAs) to be incorporated into instruments for sensing cosmic microwave background radiation. There are also potential uses for such LNAs in electronic test equipment, passive millimeter- wave imaging systems, radar receivers, communication receivers, and systems for detecting hidden weapons. The main advantage afforded by these MMIC LNAs, relative to prior MMIC LNAs, is that their coverage of the 120-to-180-GHz frequency band makes them suitable for reuse in a wider variety of applications without need to redesign them. Each of these MMIC amplifiers includes InP transistors and coplanar waveguide circuitry on a 50- mthick chip (see Figure 1). Coplanar waveguide transmission lines are used for both applying DC bias and matching of input and output impedances of each transistor stage. Via holes are incorporated between top and bottom ground planes to suppress propagation of electromagnetic modes in the substrate. On the basis of computational simulations, each of these amplifiers was expected to operate with a small-signal gain of 14 dB and a noise figure of 4.3 dB. At the time of writing this article, measurements of noise figures had not been reported, but on-chip measurements had shown gains approaching their simulated values (see Figure 2).

  10. Ni0.6Zn0.4Fe2O4铁氧体纳米晶与微米晶300MHz~2GHz的磁导率比较%Comparison of permeability between Ni0.6Zn0.4Fe2O4 nanocrystalline and microcrystalline in 300 MHz-2 GHz frequency range

    Institute of Scientific and Technical Information of China (English)

    李家明; 伍俊夫; 汪忠柱

    2013-01-01

      用水热法制备了平均晶粒尺寸为40 nm 的Ni0.6Zn0.4Fe2O4铁氧体八面体颗粒,同时采用溶胶-凝胶高温烧结法合成 Ni0.6Zn0.4Fe2O4微米晶颗粒。用矢量网络分析仪测试了铁氧体/石蜡混合材料在300MHz~2GHz频段的复磁导率和复介电常数。实验结果表明Ni0.6Zn0.4Fe2O4铁氧体纳米晶粒样品与微米晶样品相比具有更高的磁导率(实部 rµ′在3.3~1.65之间,磁导率虚部 rµ′在1.1左右)、更大的磁损耗以及更优异的微波吸收特性。%Ni0.6Zn0.4Fe2O4 ferrite octahedral nanoparticles with mean crystallite size of about 40 nm were synthesized via hydrothermal route, and the Ni0.6Zn0.4Fe2O4 microcrystalline particles were also synthesized by sol-gel high temperature sintering method. In 300MHz-2GHz frequency range, the complex permeability and permittivity for Ni0.6Zn0.4Fe2O4/wax composites were measured by vector network analyzer. The results showed that Ni0.6Zn0.4Fe2O4 nanoparticle sample presents higher microwave permeability, magnetic loss tangent and more excellent microwave absorption property than microcrystalline sample.

  11. Improved design for low noise Nb SIS devices for Band 9 of ALMA (600 - 720 GHz)

    NARCIS (Netherlands)

    Lodewijk, C. F. J.; Kroug, M.; Klapwijk, T. M.; Mena, F. P.; Baryshev, A. M.; Wild, W.

    2005-01-01

    Superconducting-insulating-superconducting mixers incorporating a novel design were fabricated and evaluated for heterodyne detection in the frequency range of 600 to 720 GHz (ALMA Band 9). The improved design consists in tapering the corners of the RF transformer and a careful optimization of the d

  12. Coherence bandwidth characterization in an urban microcell at 62.4 GHz

    DEFF Research Database (Denmark)

    Sánchez, M. G.; Hammoudeh, A. M.; Grindrod, E.

    2000-01-01

    Results of experiments made at 62.4 GHz in an urban mobile radio environment to characterize the coherence bandwidth are presented. The correlation coefficients between signal envelopes separated in frequency are measured and expressed as functions of distance from the base station. Due to the hi...

  13. A Robust 43 GHz VCO in Standard CMOS for OC-768 SONET Applications

    NARCIS (Netherlands)

    Wel, van der Arnoud P.; Gierkink, Sander L.J.; Frye, Robert C.; Bocuzzi, Vito; Nauta, Bram; Franca, J.; Koch, R.

    2003-01-01

    In this paper, we present a 43 GHz VCO in 0.13μm CMOS for use in SONET OC-768 optical networks. The design has a large tune range of 4.2%, which is sufficient to hold the design center frequency over anticipated process spread and temperature variation. A tuned output buffer is used to provide 1.3 V

  14. One Innovation of Mechanical Polishing Apparatus for Surface Treatment of 6 GHz TESLA Superconducting Cavity

    Institute of Scientific and Technical Information of China (English)

    YU; Guo-long; A.A.Rossi; R.K.Thakur; V.Palmieri

    2013-01-01

    6 GHz spinning seamless superconducting radio frequency(SRF)cavities are a very useful tool for testing alternative surface treatments in the fabrication of TESLA cavity.However,the surface is damaged in internal part for the using of the collapsible mandrel during spinning.The first important step of the

  15. Coherence bandwidth characterization in an urban microcell at 62.4 GHz

    DEFF Research Database (Denmark)

    Sánchez, M. G.; Hammoudeh, A. M.; Grindrod, E.

    2000-01-01

    Results of experiments made at 62.4 GHz in an urban mobile radio environment to characterize the coherence bandwidth are presented. The correlation coefficients between signal envelopes separated in frequency are measured and expressed as functions of distance from the base station. Due to the hi...

  16. 3D printed 20/30-GHz dual-band offset stepped-reflector antenna

    DEFF Research Database (Denmark)

    Menendez, Laura G.; Kim, Oleksiy S.; Persson, Frank

    2015-01-01

    with a peak directivity of 36.7 dB and 40.4 dB at 20 and 30 GHz, respectively; this corresponds to an aperture efficiency of 61 % and 64 %, respectively. These results demonstrate that 3D printing is a viable manufacturing technology for medium-sized high-frequency antennas....

  17. Phillips SA8016BW 2.5 GHz Synthesizer SEE Testing

    Science.gov (United States)

    Carts, Marty; Ladbury, Ray; Marshall, Paul W.; Mackey, Susan

    2008-01-01

    This viewgraph presentation reviews the Single Event Effects (SEE) testing of the Phillips SA8016BW 2.5 GHz Synthesizer that was chose by the GLAST Program for Frequency Generation. Included in this are diagrams of the phased-locked loop (PLL), the synthesizer, and heater.

  18. Advanced Wireless Local Area Networks in the Unlicensed Sub-1GHz ISM-bands

    NARCIS (Netherlands)

    Aust, S.H.

    2014-01-01

    This dissertation addresses the challenges of wireless local area networks (WLANs) that operate in the unlicensed sub-1GHz industrial, scientific, and medical (ISM) band. Frequencies in the 900MHz spectrum enable a wider coverage due to the longer propagation characteristics of the radio waves. To u

  19. Low-jitter and high-power 40 GHz all-active mode-locked lasers

    DEFF Research Database (Denmark)

    Yvind, Kresten; Larsson, David; Christiansen, Lotte Jin

    2004-01-01

    A novel design strategy for the epitaxial structure of monolithic mode-locked semiconductor lasers is presented. Using an all-active design, we fabricate 40-GHz lasers generating 2.8-ps almost chirp-free pulses with record low high-frequency jitter and more than 7-mW fiber coupled output power....

  20. COMPREHENSIVE ANALYSIS OF PREBIOTIC PROPENAL UP TO 660 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Daly, A. M.; Bermúdez, C.; Kolesniková, L.; Alonso, J. L., E-mail: Adam.M.Daly@jpl.nasa.gov [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Área de Química-Física, Laboratorios de Espectroscopia y Bioespectroscopia, Parque Científico UVa, Unidad Asociada CSIC, Universidad de Valladolid, E-47011 Valladolid (Spain)

    2015-06-22

    Since interstellar detection of propenal is only based on two rotational transitions in the centimeter wave region, its high resolution rotational spectrum has been measured up to 660 GHz and fully characterized by assignment of more than 12,000 transitions to provide direct laboratory data to the astronomical community. Spectral assignments and analysis include transitions from the ground state of the trans and cis isomers, three trans-{sup 13}C isotopologues, and ten excited vibrational states of the trans form. Combining new millimeter and submillimeter data with those from the far-infrared region has yielded the most precise set of spectroscopic constants of trans-propenal obtained to date. Newly determined rotational constants, centrifugal distortion constants, vibrational energies, and Coriolis and Fermi interaction constants are given with high accuracy and were used to predict transition frequencies and intensities over a wide frequency range. Results of this work should facilitate astronomers further observation of propenal in the interstellar medium.

  1. Ultra High-Speed CMOS Circuits Beyond 100 GHz

    CERN Document Server

    Gharavi, Sam

    2012-01-01

    The book covers the CMOS-based millimeter wave circuits and devices and presents methods and design techniques to use CMOS technology for circuits operating beyond 100 GHz.� Coverage includes a detailed description of both active and passive devices, including modeling techniques and performance optimization. Various mm-wave circuit blocks are discussed, emphasizing their design distinctions from low-frequency design methodologies. This book also covers a device-oriented circuit design technique that is essential for ultra high speed circuits and gives some examples of device/circuit co-design that can be used for mm-wave technology. Offers a detailed description of high frequency device modeling from a circuit designer perspective; Presents a set of techniques for optimizing the performance of CMOS for mm-wave technology, including noise and low noise design for mm-wave; Introduces circuit/device co-design techniques. �

  2. Identification of the SPS Impedance at 1.4 GHz

    CERN Document Server

    Argyropoulos, T; Damerau, H; Esteban Müller, J F; Shaposhnikova, E N; Timko, H

    2013-01-01

    In the SPS spectrum measurements of very long single bunches were used in the past to identify sources of longitudinal microwave instability. Shielding of the identified objects significantly improved the beam stability. However, longitudinal instabilities are still one of the limitations for high intensity LHC beams in the SPS. Recently the same measurement technique was used again, revealing a strong high frequency resonance. During the slow de-bunching with the RF switched off, the presence of different resonant impedances leads to a line density modulation at the resonant frequencies. Longitudinal profiles of bunches of various intensities were acquired. For sufficiently high intensities their spectra show a fast growing and strong modulation at 1.4 GHz. Measurements using two transverse optics with different transition energy are compared. Reproducing the measurements with numerical simulations, including the known SPS longitudinal impedances, allowed the parameter range of this unknown source to be dete...

  3. A 56.4-to-63.4 GHz Multi-Rate All-Digital Fractional-N PLL for FMCW Radar Applications in 65 nm CMOS

    NARCIS (Netherlands)

    Wu, W.; Staszewski, R.B.; Long, J.R.

    2014-01-01

    A mm-wave digital transmitter based on a 60 GHz all-digital phase-locked loop (ADPLL) with wideband frequency modulation (FM) for FMCW radar applications is proposed. The fractional-N ADPLL employs a high-resolution 60 GHz digitally controlled oscillator (DCO) and is capable of multi-rate two-point

  4. A 12 GHz broadband latching circulator

    Science.gov (United States)

    Katoh, Y.; Konishi, H.; Sakamoto, K.

    The two kinds of latching circulators, external return path and internal return path, are defined, noting the advantages (faster switching speed, lower switching energy, less complicated fabrication) offered by the internal configuration. It is noted, however, that this kind of circulator is difficult to make broadband because the return paths do not seem to act as part of the ferrite junction. The development of a 12-GHz broadband, internal return path circulator with impedance matching transformer and in-phase adjustment screws designed using eigenvalue measurement is described. In describing the operating characteristics, it is noted that more than 25 dB isolation over 11 GHz to 13.5 GHz and 0.25 dB insertion loss is obtained.

  5. Amplifier Module for 260-GHz Band Using Quartz Waveguide Transitions

    Science.gov (United States)

    Padmanabhan, Sharmila; Fung, King Man; Kangaslahti, Pekka P.; Peralta, Alejandro; Soria, Mary M.; Pukala, David M.; Sin, Seth; Samoska, Lorene A.; Sarkozy, Stephen; Lai, Richard

    2012-01-01

    Packaging of MMIC LNA (monolithic microwave integrated circuit low-noise amplifier) chips at frequencies over 200 GHz has always been problematic due to the high loss in the transition between the MMIC chip and the waveguide medium in which the chip will typically be used. In addition, above 200 GHz, wire-bond inductance between the LNA and the waveguide can severely limit the RF matching and bandwidth of the final waveguide amplifier module. This work resulted in the development of a low-loss quartz waveguide transition that includes a capacitive transmission line between the MMIC and the waveguide probe element. This capacitive transmission line tunes out the wirebond inductance (where the wire-bond is required to bond between the MMIC and the probe element). This inductance can severely limit the RF matching and bandwidth of the final waveguide amplifier module. The amplifier module consists of a quartz E-plane waveguide probe transition, a short capacitive tuning element, a short wire-bond to the MMIC, and the MMIC LNA. The output structure is similar, with a short wire-bond at the output of the MMIC, a quartz E-plane waveguide probe transition, and the output waveguide. The quartz probe element is made of 3-mil quartz, which is the thinnest commercially available material. The waveguide band used is WR4, from 170 to 260 GHz. This new transition and block design is an improvement over prior art because it provides for better RF matching, and will likely yield lower loss and better noise figure. The development of high-performance, low-noise amplifiers in the 180-to- 700-GHz range has applications for future earth science and planetary instruments with low power and volume, and astrophysics array instruments for molecular spectroscopy. This frequency band, while suitable for homeland security and commercial applications (such as millimeter-wave imaging, hidden weapons detection, crowd scanning, airport security, and communications), also has applications to

  6. Feasibility studies for a wireless 60 GHz tracking detector readout

    Science.gov (United States)

    Dittmeier, S.; Schöning, A.; Soltveit, H. K.; Wiedner, D.

    2016-09-01

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m2) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

  7. Feasibility studies for a wireless 60 GHz tracking detector readout

    Energy Technology Data Exchange (ETDEWEB)

    Dittmeier, S., E-mail: dittmeier@physi.uni-heidelberg.de; Schöning, A.; Soltveit, H.K.; Wiedner, D.

    2016-09-11

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m{sup 2}) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

  8. Optical-fiber-connected 300-GHz FM-CW radar system

    Science.gov (United States)

    Kanno, Atsushi; Sekine, Norihiko; Kasamatsu, Akifumi; Yamamoto, Naokatsu; Kawanishi, Tetsuya

    2017-05-01

    300-GHz frequency-modulated continuous-wave (FM-CW) radar system operated by radio over fiber technologies is configured and demonstrated. Centralized signal generator, which is based on an optical frequency comb generation, provides high-precise FM-CW radar signal. The optical signal is easy to be transported to radar heads through an optical fiber network. Optical-modulator-based optical frequency comb generator is utilized as an optical frequency multiplier from a microwave signal to a 300-GHz terahertz signal by an optical modulation technique. In the study, we discuss the configuration of the network, signal generator and remote radar head for terahertz-wave multi-static radar system.

  9. Low-noise integrated balanced SIS mixer for 787-950 GHz

    Science.gov (United States)

    Fujii, Yasunori; Kojima, Takafumi; Gonzalez, Alvaro; Asayama, Shin'ichiro; Kroug, Matthias; Kaneko, Keiko; Ogawa, Hideo; Uzawa, Yoshinori

    2017-02-01

    We developed a low-noise, compact, balanced superconductor-insulator-superconductor (SIS) mixer, operating in the 787-950 GHz radio frequency range. A waveguide mixer block was designed to integrate all the key components, such as a radio frequency (RF) 90° hybrid coupler, two identical SIS mixer chips, bias-tees, and an intermediate frequency power-combiner. The RF waveguide 90° hybrid coupler consists of branch lines with wide slots optimized by numerical simulation, for ease of fabrication. The balanced mixer was installed into a cartridge type receiver, originally developed for the Atacama Large Millimeter/submillimeter Array Band 10 (787-950 GHz). The receiver demonstrated double sideband noise temperatures of approximately 200 K for most of the band, without any correction for loss in front of the receiver. The local oscillator noise rejection ratio was estimated to be more than 15 dB within the measured frequency range.

  10. Lumped element kinetic inductance detectors maturity for space-borne instruments in the range between 80 and 180~GHz

    CERN Document Server

    Catalano, A; Bourrion, O; Calvo, M; Coiffard, G; D'Addabbo, A; Goupy, J; Sueur, H Le; Macìas-Pérez, J; Monfardini, A

    2015-01-01

    This work intends to give the state-of-the-art of our knowledge of the performance of LEKIDs at millimetre wavelengths (from 80 to 180~GHz). We evaluate their optical sensitivity under typical background conditions and their interaction with ionising particles. Two LEKID arrays, originally designed for ground-based applications and composed of a few hundred pixels each, operate at a central frequency of 100, and 150~GHz ($\\Delta \

  11. Optical frequency comb based multi-band microwave frequency conversion for satellite applications.

    Science.gov (United States)

    Yang, Xinwu; Xu, Kun; Yin, Jie; Dai, Yitang; Yin, Feifei; Li, Jianqiang; Lu, Hua; Liu, Tao; Ji, Yuefeng

    2014-01-13

    Based on optical frequency combs (OFC), we propose an efficient and flexible multi-band frequency conversion scheme for satellite repeater applications. The underlying principle is to mix dual coherent OFCs with one of which carrying the input signal. By optically channelizing the mixed OFCs, the converted signal in different bands can be obtained in different channels. Alternatively, the scheme can be configured to generate multi-band local oscillators (LO) for widely distribution. Moreover, the scheme realizes simultaneous inter- and intra-band frequency conversion just in a single structure and needs only three frequency-fixed microwave sources. We carry out a proof of concept experiment in which multiple LOs with 2 GHz, 10 GHz, 18 GHz, and 26 GHz are generated. A C-band signal of 6.1 GHz input to the proposed scheme is successfully converted to 4.1 GHz (C band), 3.9 GHz (C band) and 11.9 GHz (X band), etc. Compared with the back-to-back (B2B) case measured at 0 dBm input power, the proposed scheme shows a 9.3% error vector magnitude (EVM) degradation at each output channel. Furthermore, all channels satisfy the EVM limit in a very wide input power range.

  12. A study of broadband Faraday rotation and polarization behaviour over 1.3--10 GHz in 36 discrete radio sources

    CERN Document Server

    Anderson, C S; Feain, I J

    2016-01-01

    We present a broadband polarization analysis of 36 discrete polarized radio sources over a very broad, densely-sampled frequency band. Our sample was selected on the basis of polarization behaviour apparent in narrowband archival data at 1.4 GHz: half the sample show complicated frequency-dependent polarization behaviour (i.e. Faraday complexity) at these frequencies, while half show comparatively simple behaviour (i.e. they appear Faraday simple). We re-observed the sample using the Australia Telescope Compact Array (ATCA) in full polarization, with 6 GHz of densely sampled frequency coverage spanning 1.3 to 10 GHz. We have devised a general polarization modelling technique that allows us to identify multiple polarized emission components in a source, and to characterize their properties. We detect Faraday complex behaviour in almost every source in our sample. Several sources exhibit particularly remarkable polarization behaviour. By comparing our new and archival data, we have identified temporal variabili...

  13. Characterization of the CTS 12 and 14 GHz communications links - Preliminary measurements and evaluation. [Communications Technology Satellite

    Science.gov (United States)

    Ippolito, L. J.

    1976-01-01

    The Communications Link Characterization Experiment is designed to characterize the radio frequency links of the Communications Technology Satellite. The experiment is twofold: (1) it will study the natural characteristics in the CTS frequency bands (14 GHz uplink, and 12 GHz downlink) including attenuation and signal degradation due primarily to absorption and scattering induced by precipitation, and (2) it will perform environmental measurements for the characterization of man-made, earth-based signals which could interfere with the uplink frequency bands of the satellite.

  14. Microphonics detuning compensation in 3.9 GHZ superconducting RF cavities

    Energy Technology Data Exchange (ETDEWEB)

    Ruben Carcagno et al.

    2003-10-20

    Mechanical vibrations can detune superconducting radio frequency (SCRF) cavities unless a tuning mechanism counteracting the vibrations is present. Due to their narrow operating bandwidth and demanding mechanical structure, the 13-cell 3.9GHz SCRF cavities for the Charged Kaons at Main Injector (CKM) experiment at Fermilab are especially susceptible to this microphonic phenomena. We present early results correlating RF frequency detuning with cavity vibration measurements for CKM cavities; initial detuning compensation results with piezoelectric actuators are also presented.

  15. Híbrido rat-race miniaturizado para la banda ISM 2,4 GHZ

    Directory of Open Access Journals (Sweden)

    Sebastián Rodríguez Páez

    2014-10-01

    Full Text Available This paper presents the design, implementation and evaluation of a miniaturized Rat-race hybrid implemented in substrate CER-60 with microstrip transmission lines in a novel space-filling curve. This circuit is the main research's result of the project PS 3206funded by the Pontificia Universidad Javeriana. The hybrid achieves a miniaturization of 73 %, it operates in the 2.4 GHz ISM band, with an optimum operating frequency 2.56 GHz and a fractional band width of17.15%.

  16. A 4.9-GHz Low Power, Low Jitter, LC Phase Locked Loop

    CERN Document Server

    Liu, T

    2010-01-01

    This paper present a low power, low jitter LC phase locked loop (PLL) which has been designed and fabricated in a commercial 0.25-µm Silicon-on-Sapphire CMOS technology. Random jitter and deterministic jitter of the PLL is 1.3 ps and 7.5 ps, respectively. The measured tuning range, from 4.6 to 5.0 GHz, is narrower than the expected value of from 3.8 to 5.0 GHz. The narrow tuning range issue has been investigated and traced to the first stage of the divider chain. The power consumption at the central frequency is 111 mW.

  17. 5. 8 GHz ophthalmic microwave applicator for treatment of choroidal melanoma

    Energy Technology Data Exchange (ETDEWEB)

    Finger, P.T.; Packer, S.; Svitra, P.; Paglione, R.W.; Albert, D.M.; Chess, J.

    1983-01-01

    We report on the use of a 5.8 GHz microwave applicator to treat choroidal melanoma (Greene) in rabbits. The physical requirements needed to treat these intraocular tumors are quite different from those encountered elsewhere in the body. From a trans-scleral approach the penetration needed is minimal (5 to 10 mm.). The fibrous sclera is the only structure between the heat source and the tumor. The sclera has a relatively low water content when compared to tumor. This fact in addition to the frequency dependent interactions of tissue and electromagnetic radiation, results in an advantage to the use of the 5.8 GHz microwave device in treating intraocular malignancies.

  18. Computer Aided Design and Analysis of a 2-4 GHz Broadband Balanced Microstrip Amplifier

    OpenAIRE

    S. H. Ibrahim

    2012-01-01

    In this paper, a computer-aided design and analysis of a 2-4 GHz broadband balanced microstrip amplifier using a full computer simulation program developed by the author and others is presented. A short and efficient CAD procedure for broadband amplifier design is introduced. The first step is to design an initial narrow-band high gain microstrip amplifier at 3-GHz central frequency. The second step is to optimize the initial lengths and widths of the input and output microstrip-matching circ...

  19. 3D printed 20/30-GHz dual-band offset stepped-reflector antenna

    DEFF Research Database (Denmark)

    Menendez, Laura G.; Kim, Oleksiy S.; Persson, Frank

    2015-01-01

    with a peak directivity of 36.7 dB and 40.4 dB at 20 and 30 GHz, respectively; this corresponds to an aperture efficiency of 61 % and 64 %, respectively. These results demonstrate that 3D printing is a viable manufacturing technology for medium-sized high-frequency antennas.......This paper documents the manufacturing by selective laser sintering of a 20/30 GHz dual-band circularly polarized offset stepped-reflector antenna for K- and Ka-band satellite communication. The manufactured antenna has been measured at the DTU-ESA Spherical Near-Field Antenna Test Facility...

  20. Development of Low-Noise Small-Area 24 GHz CMOS Radar Sensor

    OpenAIRE

    2016-01-01

    We present a low-noise small-area 24 GHz CMOS radar sensor for automotive collision avoidance. This sensor is based on direct-conversion pulsed-radar architecture. The proposed circuit is implemented using TSMC 0.13 μm RF (radio frequency) CMOS (fT/fmax=120/140 GHz) technology, and it is powered by a 1.5 V supply. This circuit uses transmission lines to reduce total chip size instead of real bulky inductors for input and output impedance matching. The layout techniques for RF are used to redu...

  1. A LOW-PHASE NOISE FREQUENCY MULTIPLIER CHAIN ...

    African Journals Online (AJOL)

    Consequently, the driving crystal oscillators and the first multiplier .... the upper cut off frequency of the system and its asymptotic slope. ..... (SMHz}, the order of multipliction of the. "difference" ... upto 300GHz. To go higher in frequency it is.

  2. Multi-frequency recirculating planar magnetrons

    Science.gov (United States)

    Greening, Geoffrey B.; Jordan, Nicholas M.; Exelby, Steven C.; Simon, David H.; Lau, Y. Y.; Gilgenbach, Ronald M.

    2016-08-01

    The multi-frequency recirculating planar magnetron (MFRPM) is the first magnetron capable of simultaneous generation of significantly different output frequencies (1 and 2 GHz) in a single operating pulse. Design and simulation of a prototype MFRPM were followed by hardware fabrication and experimental verification using the Michigan Electron Long Beam Accelerator with a Ceramic insulator at -300 kV, 1-5 kA, and 0.14-0.23 T axial magnetic field. Preliminary results demonstrated simultaneous generation of microwave pulses near 1 GHz and 2 GHz at powers up to 44 MW and 21 MW, respectively, with peak total efficiencies up to 9%.

  3. Gas spectroscopy system with 245 GHz transmitter and receiver in SiGe BiCMOS

    Science.gov (United States)

    Schmalz, Klaus; Rothbart, Nick; Borngräber, Johannes; Yilmaz, Selahattin Berk; Kissinger, Dietmar; Hübers, Heinz-Wilhelm

    2017-02-01

    The implementation of an integrated mm-wave transmitter (TX) and receiver (RX) in SiGe BiCMOS or CMOS technology offers a path towards a compact and low-cost system for gas spectroscopy. Previously, we have demonstrated TXs and RXs for spectroscopy at 238 -252 GHz and 495 - 497 GHz using external phase-locked loops (PLLs) with signal generators for the reference frequency ramps. Here, we present a more compact system by using two external fractional-N PLLs allowing frequency ramps for the TX and RX, and for TX with superimposed frequency shift keying (FSK) or reference frequency modulation realized by a direct digital synthesizer (DDS) or an arbitrary waveform generator. The 1.9 m folded gas absorption cell, the vacuum pumps, as well as the TX and RX are placed on a portable breadboard with dimensions of 75 cm x 45 cm. The system performance is evaluated by high-resolution absorption spectra of gaseous methanol at 13 Pa for 241 - 242 GHz. The 2f (second harmonic) content of the absorption spectrum of the methanol was obtained by detecting the IF power of RX using a diode power sensor connected to a lock-in amplifier. The reference frequency modulation reveals a higher SNR (signal-noise-ratio) of 98 within 32 s acquisition compared to 66 for FSK. The setup allows for jumping to preselected frequency regions according to the spectral signature thus reducing the acquisition time by up to one order of magnitude.

  4. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  5. A 24GHz Radar Receiver in CMOS

    NARCIS (Netherlands)

    Kwok, K.C.

    2015-01-01

    This thesis investigates the system design and circuit implementation of a 24GHz-band short-range radar receiver in CMOS technology. The propagation and penetration properties of EM wave offer the possibility of non-contact based remote sensing and through-the-wall imaging of distance stationary or

  6. A Prediction Study of Path Loss Models from 2-73.5 GHz in an Urban-Macro Environment

    DEFF Research Database (Denmark)

    Thomas, Timothy; Rybakowski, Marcin; Sun, Shu

    2016-01-01

    It is becoming clear that 5G wireless systems will encompass frequencies from around 500 MHz all the way to around 100 GHz. To adequately assess the performance of 5G systems in these different bands, path loss (PL) models will need to be developed across this wide frequency range. The PL models ...

  7. TWT design requirements for 30/20 GHz digital communications' satellite

    Science.gov (United States)

    Stankiewicz, N.; Anzic, G.

    1979-01-01

    The rapid growth of communication traffic (voice, data, and video) requires the development of additional frequency bands before the 1990's. The frequencies currently in use for satellite communications at 6/4 GHz are crowded and demands for 14/12 GHz systems are increasing. Projections are that these bands will be filled to capacity by the late 1980's. The next higher frequency band allocated for satellite communications is at 30/20 GHz. For interrelated reasons of efficiency, power level, and system reliability criteria, a candidate for the downlink amplifier in a 30/20 GHz communications' satellite is a dual mode traveling wave tube (TWT) equipped with a highly efficient depressed collector. A summary is given of the analyses which determine the TWT design requirements. The overall efficiency of such a tube is then inferred from a parametric study and from experimental data on multistaged depressed collectors. The expected TWT efficiency at 4 dB below output saturation is 24 percent in the high mode and 22 percent in the low mode.

  8. A 12 GHZ 50 MW Klystron for Support of Accelerator Research

    Energy Technology Data Exchange (ETDEWEB)

    Sprehn, Daryl; /SLAC; Haase, Andrew; /SLAC; Jensen, Aaron; /SLAC; Jongewaard, Erik; /SLAC; Nantista, Christopher; /SLAC; Vlieks, Arnold; /SLAC

    2011-05-31

    A 12 GHz 50MW X-band klystron is under development at the SLAC National Accelerator Laboratory Klystron Department. The klystron will be fabricated to support programs currently underway at three European Labs; CERN, PSI, and INFN Trieste. The choice of frequency selection was due to the CLIC RF frequency changing from 30 GHz to the European X-band frequency of 11.99 GHz in 2008. Since the Klystron Department currently builds 50MW klystrons at 11.424 GHz known collectively as the XL4 klystrons, it was deemed cost-effective to utilize many XL4 components by leaving the gun, electron beam transport, solenoid magnet and collector unchanged. To realize the rf parameters required, the rf cavities and rf output hardware were necessarily altered. Some improvements to the rf design have been made to reduce operating gradients and increase reliability. Changes in the multi-cell output structure, waveguide components, and the window will be discussed along with testing of the devices. Five klystrons known as XL5 klystrons are scheduled for production over the next two years.

  9. A 140 GHz pulsed EPR/212 MHz NMR spectrometer for DNP studies

    Science.gov (United States)

    Smith, Albert A.; Corzilius, Björn; Bryant, Jeffrey A.; DeRocher, Ronald; Woskov, Paul P.; Temkin, Richard J.; Griffin, Robert G.

    2012-10-01

    We described a versatile spectrometer designed for the study of dynamic nuclear polarization (DNP) at low temperatures and high fields. The instrument functions both as an NMR spectrometer operating at 212 MHz (1H frequency) with DNP capabilities, and as a pulsed-EPR operating at 140 GHz. A coiled TE011 resonator acts as both an NMR coil and microwave resonator, and a double balanced (1H, 13C) radio frequency circuit greatly stabilizes the NMR performance. A new 140 GHz microwave bridge has also been developed, which utilizes a four-phase network and ELDOR channel at 8.75 GHz, that is then multiplied and mixed to obtain 140 GHz microwave pulses with an output power of 120 mW. Nutation frequencies obtained are as follows: 6 MHz on S = 1/2 electron spins, 100 kHz on 1H, and 50 kHz on 13C. We demonstrate basic EPR, ELDOR, ENDOR, and DNP experiments here. Our solid effect DNP results demonstrate an enhancement of 144 and sensitivity gain of 310 using OX063 trityl at 80 K and an enhancement of 157 and maximum sensitivity gain of 234 using Gd-DOTA at 20 K, which is significantly better performance than previously reported at high fields (⩾3 T).

  10. Folded down-conversion mixer for a 60 GHz receiver architecture in 65-nm CMOS technology

    Institute of Scientific and Technical Information of China (English)

    Najam Muhammad AMIN; Zhi-gong WANG‡; Zhi-qun LI

    2014-01-01

    We present the design of a folded down-conversion mixer which is incorporated at the final down-conversion stage of a 60 GHz receiver. The mixer employs an ac-coupled current reuse transconductance stage. It performs well under low supply voltages, and is less sensitive to temperature variations and process spread. The mixer operates at an input radio frequency (RF) band ranging from 10.25 to 13.75 GHz, with a fixed local oscillator (LO) frequency of 12 GHz, which down-converts the RF band to an intermediate frequency (IF) band ranging from dc to 1.75 GHz. The mixer is designed in a 65 nm low power (LP) CMOS process with an active chip area of only 0.0179 mm2. At a nominal supply voltage of 1.2 V and an IF of 10 MHz, a maximum voltage conversion gain (VCG) of 9.8 dB, a double sideband noise figure (DSB-NF) of 11.6 dB, and a linearity in terms of input 1 dB compression point (Pin,1dB) of−13 dBm are measured. The mixer draws a current of 5 mA from a 1.2 V supply dissipating a power of only 6 mW.

  11. A 140 GHz pulsed EPR/212 MHz NMR spectrometer for DNP studies.

    Science.gov (United States)

    Smith, Albert A; Corzilius, Björn; Bryant, Jeffrey A; DeRocher, Ronald; Woskov, Paul P; Temkin, Richard J; Griffin, Robert G

    2012-10-01

    We described a versatile spectrometer designed for the study of dynamic nuclear polarization (DNP) at low temperatures and high fields. The instrument functions both as an NMR spectrometer operating at 212 MHz ((1)H frequency) with DNP capabilities, and as a pulsed-EPR operating at 140 GHz. A coiled TE(011) resonator acts as both an NMR coil and microwave resonator, and a double balanced ((1)H, (13)C) radio frequency circuit greatly stabilizes the NMR performance. A new 140 GHz microwave bridge has also been developed, which utilizes a four-phase network and ELDOR channel at 8.75 GHz, that is then multiplied and mixed to obtain 140 GHz microwave pulses with an output power of 120 mW. Nutation frequencies obtained are as follows: 6 MHz on S=1/2 electron spins, 100 kHz on (1)H, and 50 kHz on (13)C. We demonstrate basic EPR, ELDOR, ENDOR, and DNP experiments here. Our solid effect DNP results demonstrate an enhancement of 144 and sensitivity gain of 310 using OX063 trityl at 80 K and an enhancement of 157 and maximum sensitivity gain of 234 using Gd-DOTA at 20 K, which is significantly better performance than previously reported at high fields (≥3 T).

  12. On the origin of 140 GHz emission from the 4 July 2012 solar flare

    CERN Document Server

    Tsap, Yuriy T; Morgachev, Alexander S; Motorina, Galina G; Kontar, Eduard P; Nagnibeda, Valery G; Strekalova, Polina V

    2016-01-01

    The sub-THz event observed on the 4 July 2012 with the Bauman Moscow State Technical University Radio Telescope RT-7.5 at 93 and 140~GHz as well as Kislovodsk and Mets\\"ahovi radio telescopes, Radio Solar Telescope Network (RSTN), GOES, RHESSI, and SDO orbital stations is analyzed. The spectral flux between 93 and 140 GHz has been observed increasing with frequency. On the basis of the SDO/AIA data the differential emission measure has been calculated. It is shown that the thermal coronal plasma with the temperature above 0.5~MK cannot be responsible for the observed sub-THz flare emission. The non-thermal gyrosynchrotron mechanism can be responsible for the microwave emission near $10$~GHz but the observed millimeter spectral characteristics are likely to be produced by the thermal bremsstrahlung emission from plasma with a temperature of about 0.1~MK.

  13. On the origin of 140 GHz emission from the 4 July 2012 solar flare

    Science.gov (United States)

    Tsap, Yuriy T.; Smirnova, Victoria V.; Morgachev, Alexander S.; Motorina, Galina G.; Kontar, Eduard P.; Nagnibeda, Valery G.; Strekalova, Polina V.

    2016-04-01

    The sub-THz event observed on the 4 July 2012 with the Bauman Moscow State Technical University Radio Telescope RT-7.5 at 93 and 140 GHz as well as Kislovodsk and Metsähovi radio telescopes, Radio Solar Telescope Network (RSTN), GOES, RHESSI, and SDO orbital stations is analyzed. The spectral flux between 93 and 140 GHz has been observed increasing with frequency. On the basis of the SDO/AIA data the differential emission measure has been calculated. It is shown that the thermal coronal plasma with the temperature above 0.5 MK cannot be responsible for the observed sub-THz flare emission. The non-thermal gyrosynchrotron mechanism can be responsible for the microwave emission near 10 GHz but the observed millimeter spectral characteristics are likely to be produced by the thermal bremsstrahlung emission from plasma with a temperature of about 0.1 MK.

  14. MEMS-based tunable terahertz wire-laser over 330 GHz.

    Science.gov (United States)

    Qin, Qi; Reno, John L; Hu, Qing

    2011-03-01

    We demonstrate continuous tuning of a terahertz quantum cascade wire laser over a broad range of ∼330 GHz (∼8.6% of the 3.85 THz center frequency) with single-mode operation. Tuning is achieved with a narrow laser ridge (∼λ(o)/8) and a moveable MEMS (microelectromechanical systems) side object (plunger) to manipulate the transverse optical mode. The frictionless MEMS plunger enables continuous and reversible tuning. We demonstrate ∼30 GHz redshift tuning using a silicon plunger and ∼300 GHz blueshift tuning using a metal plunger. The blueshift tuning range is limited by the bandwidth of the gain medium rather than the tuning mechanism.

  15. X-(2) Modulator With 40-GHz Modulation Utilizing BaTiO3 Photonic Crystal Waveguides

    DEFF Research Database (Denmark)

    Girouard, Peter David; Chen, Pice; Jeong, Young Kyu

    2017-01-01

    Future telecommunication and data center networks as well as quantum optical communication systems will require optical modulators with wide bandwidths, large extinction, low operating voltage, and small size. We report the first quantitative demonstration of slow light enhancement of the electro......-optic (EO) coefficient in a.(2) ferroelectric waveguide at microwave modulation frequencies. This is demonstrated in a compact (1 mm) photonic crystal (PC) device with a voltage-length product (V pi . L) of 0.66 V-cm at 10 GHz and measured EO modulation out to 40 GHz. A local enhancement factor of 12...... and effective EO coefficient of 900 pm/V is measured in the PC region at a wavelength of 1530 nm. By further optimizing the PC structure, devices with EO 3-dB bandwidths greater than 40 GHz and voltage-length product of 0.16 V-cm are predicted with 100-mu m interaction length....

  16. A 94 GHz CMOS based oscillator transmitter with an on-chip meandered dipole antenna

    KAUST Repository

    Cheema, Hammad M.

    2015-10-26

    A miniaturized 94 GHz oscillator transmitter in 65nm CMOS is presented. An extremely small silicon foot-print of 0.25mm2 is achieved through meandering of the top-metal dipole antenna, conjugate matching between the oscillator and the antenna without impedance matching elements and efficient placement of the oscillator circuit within the antenna. The antenna demonstrates bandwidth of 90 to 99 GHz (10%) and a gain of -6dBi. The use of parasitic aware antenna-circuit code-sign strategy results in an accurate measured oscillation frequency of 94.1 GHz. The oscillator exhibits a measured output power of -25 dBm, phase noise of -88 dBc/Hz at 1 MHz offset and consumes 8.4mW from a 1V supply. © 2015 IEEE.

  17. On the use of passive microwaves at 37 GHz in remote sensing of vegetation

    Science.gov (United States)

    Kerr, Y. H.; Njoku, E. G.

    1993-01-01

    Recently, a number of studies have investigated the use of the 37 GHz channels of the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) for vegetation monitoring and for studying synergisms between the SMMR and the NOAA Advanced Very High Resolution Radiometer (AVHRR). The approaches are promising but raise a number of issues concerning interpretation of the results, specifically on the relative effects of vegetation and other surface and atmospheric characteristics on the observed signal. This article analyzes the 37 GHz Microwave Polarization Difference Temperature (MPDT) in terms of its sensitivity to surface and atmospheric parameters. For this, a radiative transfer model is used which indicates some limitations of the MPDT index and suggests the importance of accounting for atmospheric effects in the data analysis. An alternative approach to the MPDT, including lower SMMR frequencies than 37 GHz, is discussed.

  18. FET frequency discriminator

    Science.gov (United States)

    Mawhinney, F. D.

    1982-03-01

    The FET Frequency Discriminator is an experimental microwave frequency discriminator developed for use in a specialized set-on VCO frequency memory system. Additional development and evaluation work has been done during this program to more fully determine the applicability of the FET frequency discriminator as a low-cost, expendable receiver front-end for both surveillance and ECM systems. Various methods for adjusting the frequency-to-voltage characteristic of the discriminator as well as the effects of detector characteristics and ambient temperature changes were evaluated. A number of discriminators for use in the 7- to 11-GHz and the 11to 18-GHz bands were fabricated and tested. Interim breadboard and final packaged models were either delivered or installed in developmental frequency systems. The major limitations and deficiencies of the FET frequency discriminator that were reviewed during the program include the effects of temperature, input power level variations, nonlinearity, and component repeatability. Additional effort will be required to advance the developmental status of the FET frequency discriminator to the level necessary for inclusion in low-cost receiver systems, but the basic simplicity of the approach continues to show much promise.

  19. ATLAS 10 GHz electron cyclotron resonance ion source upgrade project

    Energy Technology Data Exchange (ETDEWEB)

    Moehs, D. P. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Vondrasek, R. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Pardo, R. C. [Argonne National Laboratory, Physics Division, Argonne, Illinois 60439 (United States); Xie, D. [Berkeley Ion Equipment Inc., Santa Clara, California 95054 (United States)

    2000-02-01

    A major upgrade of the first ATLAS 10 GHz electron cyclotron resonance (ECR) ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic-field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high-energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm, has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel, allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid coils from the existing ECR will be enclosed in an iron yoke to produce the axial mirror. Based on a current of 500 A, the final model predicts a minimum B field of 3 kG with injection and extraction mirror ratios of 4.4 and 2.9, respectively. (c) 2000 American Institute of Physics.

  20. ATLAS 10 GHz ECR ions source upgrade project.

    Energy Technology Data Exchange (ETDEWEB)

    Moehs, D. P.; Pardo, R. C.; Vondrasek, R.; Xie, D.

    1999-08-10

    A major upgrade of the first ATLAS 10 GHz ECR ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid coils from the existing ECR will be enclosed in an iron yoke to produce the axial mirror. Based on a current of 500 A, the final model predicts a minimum B field of 3 kG with injection and extraction mirror ratios of 4.4 and 2.9 respectively.

  1. The 492 GHz emission of Sgr A* constrained by ALMA

    CERN Document Server

    Liu, Hauyu Baobab; Zhao, Jun-Hui; Mills, Elisabeth A C; Requena-Torres, Miguel A; Matsushita, Satoki; Martín, Sergio; Ott, Jürgen; Morris, Mark R; Longmore, Steven N; Brinkerink, Christiaan D; Falcke, Heino

    2016-01-01

    We report linearly polarized continuum emission properties of Sgr A* at $\\sim$492 GHz, based on the Atacama Large Millimeter Array (ALMA) observations. We used the observations of the likely unpolarized continuum emission of Titan, and the observations of C\\textsc{i} line emission, to gauge the degree of spurious polarization. The Stokes I flux of 3.6$\\pm$0.72 Jy during our run is consistent with extrapolations from the previous, lower frequency observations. We found that the continuum emission of Sgr A* at $\\sim$492 GHz shows large amplitude differences between the XX and the YY correlations. The observed intensity ratio between the XX and YY correlations as a function of parallactic angle may be explained by a constant polarization position angle of $\\sim$158$^{\\circ}$$\\pm$3$^{\\circ}$. The fitted polarization percentage of Sgr A* during our observational period is 14\\%$\\pm$1.2\\%. The calibrator quasar J1744-3116 we observed at the same night can be fitted to Stokes I = 252 mJy, with 7.9\\%$\\pm$0.9\\% polariz...

  2. The Temperature of the CMB at 10 GHz

    CERN Document Server

    Fixsen, D J; Levin, S; Limon, M; Lubin, P; Mirel, P G A; Seiffert, M; Wollack, E

    2004-01-01

    We report the results of an effort to measure the low frequency portion of the spectrum of the Cosmic Microwave Background Radiation (CMB), using a balloon-borne instrument called ARCADE (Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission). These measurements are to search for deviations from a thermal spectrum that are expected to exist in the CMB due to various processes in the early universe. The radiometric temperature was measured at 10 and 30 GHz using a cryogenic open-aperture instrument with no emissive windows. An external blackbody calibrator provides an in situ reference. A linear model is used to compare the radiometer output to a set of thermometers on the instrument. The unmodeled residuals are less than 50 mK peak-to-peak with a weighted RMS of 6 mK. Small corrections are made for the residual emission from the flight train, atmosphere, and foreground Galactic emission. The measured radiometric temperature of the CMB is 2.721 +/- 0.010 K at 10 GHz and 2.694 +/- 0.032 K at 30 ...

  3. ATLAS 10 GHz electron cyclotron resonance ion source upgrade project

    CERN Document Server

    Moehs, D P; Pardo, R C; Xie, D

    2000-01-01

    A major upgrade of the first ATLAS 10 GHz electron cyclotron resonance (ECR) ion source, which began operations in 1987, is in the planning and procurement phase. The new design will convert the old two-stage source into a single-stage source with an electron donor disk and high gradient magnetic field that preserves radial access for solid material feeds and pumping of the plasma chamber. The new magnetic-field profile allows for the possibility of a second ECR zone at a frequency of 14 GHz. An open hexapole configuration, using a high-energy-product Nd-Fe-B magnet material, having an inner diameter of 8.8 cm and pole gaps of 2.4 cm, has been adopted. Models indicate that the field strengths at the chamber wall, 4 cm in radius, will be 9.3 kG along the magnet poles and 5.6 kG along the pole gaps. The individual magnet bars will be housed in austenitic stainless steel, allowing the magnet housing within the aluminum plasma chamber to be used as a water channel for direct cooling of the magnets. Eight solenoid...

  4. Deep 1.4-GHz observations of diffuse polarized emission

    CERN Document Server

    Carretti, E; Reich, W; Reich, P; Fürst, E; Bernardi, G; Cortiglioni, S; Sbarra, C

    2006-01-01

    Polarized diffuse emission observations at 1.4-GHz in a high Galactic latitude area of the northern Celestial hemisphere are presented. The 3.2 X 3.2 deg^2 field, centred at RA = 10h 58m, Dec = +42deg 18' (B1950), has Galactic coordinates l~172deg, b~+63deg and is located in the region selected as northern target of the BaR-SPOrt experiment. Observations have been performed with the Effelsberg 100-m telescope. We find that the angular power spectra of the E- and B-modes have slopes of beta_E = -1.79 +/- 0.13 and beta_B = -1.74 +/- 0.12, respectively. Because of the very high Galactic latitude and the smooth emission, a weak Faraday rotation action is expected, which allows both a fair extrapolation to Cosmic Microwave Background Polarization (CMBP) frequencies and an estimate of the contamination by Galactic synchrotron emission. We extrapolate the E-mode spectrum up to 32-GHz and confirm the possibility to safely detect the CMBP E-mode signal in the Ka band found in another low emission region (Carretti et a...

  5. A waveguide orthomode transducer for 385-500 GHz

    Science.gov (United States)

    Groppi, Christopher; Navarrini, Alessandro; Chattopadhyay, Goutam

    2010-07-01

    We describe the design, construction, and performance of a waveguide Orthomode Transducer (OMT) for the 385-500 GHz band. The OMT is based on a symmetric backward coupling structure with a square waveguide input (0.56x0.56 mm2) and two single-mode waveguide outputs: a standard WR2.2 waveguide (0.56x0.28 mm2) and an oval waveguide with full-radius corners. The OMT is rescaled from a lower frequency design that was developed for the 3 mm band; it was optimized using a commercial 3D electromagnetic simulator. The OMT consists of two mechanical blocks in split-block configuration, fabricated using a CNC micromilling machine. A first prototype copper alloy OMT employing standard UG387 flanges at all ports was fabricated and tested. From 385 to 500 GHz the measured input reflection coefficient was less than -10 dB, the isolation between the outputs was less than -25 dB, the cross polarization was less than -10 dB, and the transmission was ~-2 dB at room temperature for both polarization channels. The effects of misalignment errors in the OMT performance were studied using electromagnetic simulation. A second OMT version utilizing custom made mini-flanges and much shorter waveguides was designed and will be tested soon. This novel OMT is more tolerant to misalignment errors of the block halves and is expected to have much improved performance over the first prototype.

  6. Planck early results. IV. First assessment of the High Frequency Instrument in-flight performance

    DEFF Research Database (Denmark)

    Bréelle, E.; Bucher, M.; Cressiot, C.;

    2011-01-01

    The Planck High Frequency Instrument (HFI) is designed to measure the temperature and polarization anisotropies of the cosmic microwave background and Galactic foregrounds in six ~30% bands centered at 100, 143, 217, 353, 545, and 857 GHz at an angular resolution of 10′ (100 GHz), 7′ (143 GHz), a...

  7. Linescan camera evaluation of SSM/I 85.5 GHz sea ice retrieval

    DEFF Research Database (Denmark)

    Garrity, Caren; Lubin, Dan; Kern, Stefan

    2002-01-01

    from helicopter-borne linescan camera observations made during a cruise of the R/V Polarstern during May-June 1997. The goals are to evaluate (1) SSM/I 85.5 GHz retrievals of total sea ice concentration for climatological purposes, and (2) the ability of 85.5 GHz data to show the sea ice edge through......Retrievals of total sea ice concentration from four algorithms using the 85.5 GHz vertically and horizontally polarized channels of the Special Sensor Microwave Imager (SSM/I) over the marginal ice zone in the Barents and Greenland Seas are compared with retrievals of total sea ice concentration...... cloud cover, for operational purposes. The SSM/I 85.5 GHz channels offer a spatial resolution of 12.5 km, which is sufficient to resolve ice edge features and small polynyas; however, there is generally more atmospheric contamination of the sea ice signal at 85.5 GHz than at the lower frequencies (19...

  8. 30/20 GHz communications satellite multibeam antenna

    Science.gov (United States)

    Scott, W. G.; Luh, H. S.; Smoll, A. E.; Matthews, E. W.

    1982-01-01

    A 20 GHz downlink satellite antenna design is described. The aperture simultaneously radiates 18 fixed, 0.3 deg width pencil beams directed at 18 cities distributed over CONUS for Trunking Service. All beams use the same trunk frequency allocation for 18 reuses of the band. The same aperture also radiates six additional 0.3 deg spot beams for Customer Premises Service (CPS) for TDMA beam hopping operation to small terminals anywhere in CONUS. Each CPS beam scans one sector of CONUS and all six beams are frequency reused in a CPS band. Offset dual reflector optics are used with a feed array and multiport beam forming network (BFN). For so many frequency reuses, sidelobes per beam must be 30 to 40 dB down over CONUS. Novel dual reflector optics were devised with shaped surfaces providing low aberrations for all beam positions over CONUS (+ or - 12 BW by + or - 5 BW). Scan loss under 1 dB is calculated with nearly constant sidelobes. For each beam position, a 7-element cluster of feeds is activated in the feed array with coefficients adjusted by the BFN to maintain low sidelobes and thus high beam isolation for frequency reuse.

  9. New Love wave liquid sensor operating at 2 GHz using an integrated micro-flow channel

    Science.gov (United States)

    Assouar, M. B.; Kirsch, P.; Alnot, P.

    2009-09-01

    Surface acoustic wave (SAW) devices based on waveguide modes with shear-horizontal polarization (Love modes) are very promising for sensor applications, especially in liquid media. We present here the realization of a 2 GHz operating frequency sensor based on the SiO2/36YX LiTaO3 structure with an integrated PDMS micro-flow channel and using electron beam lithography to realize the submicronic interdigital transducers. Using our developed sensor operating at 2 GHz, we carried out alternate cycles of nitrogen and water circulating in the PDMS micro-flow channel. We measured an absolute sensitivity of -19 001 Hz mm2 ng-1 due to the interaction of the sensor with water. This sensitivity is higher than that of other devices operating at lower frequencies. The detection mechanism, including gravimetric and permittivity effects at high frequency, will be discussed.

  10. Wireless transfer of power by a 35-GHz metamaterial split-ring resonator rectenna

    CERN Document Server

    Maedler, Carsten; Yi, Adrian; Christopher, Jason; Hong, Mi K; Mertiri, Alket; House, Larry; Seren, Huseyin R; Zhang, Xin; Averitt, Richard; Mohanty, Pritiraj; Erramilli, Shyamsunder

    2016-01-01

    Wireless transfer of power via high frequency microwave radiation using a miniature split ring resonator rectenna is reported. RF power is converted into DC power by integrating a rectification circuit with the split ring resonator. The near-field behavior of the rectenna is investigated with microwave radiation in the frequency range between 20-40 GHz with a maximum power level of 17 dBm. The observed resonance peaks match those predicted by simulation. Polarization studies show the expected maximum in signal when the electric field is polarized along the edge of the split ring resonator with the gap and minimum for perpendicular orientation. The efficiency of the rectenna is on the order of 1% for a frequency of 37.2 GHz. By using a cascading array of 9 split ring resonators the output power was increased by a factor of 20.

  11. A 12 GHz wavelength spacing multi-wavelength laser source for wireless communication systems

    Science.gov (United States)

    Peng, P. C.; Shiu, R. K.; Bitew, M. A.; Chang, T. L.; Lai, C. H.; Junior, J. I.

    2017-08-01

    This paper presents a multi-wavelength laser source with 12 GHz wavelength spacing based on a single distributed feedback laser. A light wave generated from the distributed feedback laser is fed into a frequency shifter loop consisting of 50:50 coupler, dual-parallel Mach-Zehnder modulator, optical amplifier, optical filter, and polarization controller. The frequency of the input wavelength is shifted and then re-injected into the frequency shifter loop. By re-injecting the shifted wavelengths multiple times, we have generated 84 optical carriers with 12 GHz wavelength spacing and stable output power. For each channel, two wavelengths are modulated by a wireless data using the phase modulator and transmitted through a 25 km single mode fiber. In contrast to previously developed schemes, the proposed laser source does not incur DC bias drift problem. Moreover, it is a good candidate for radio-over-fiber systems to support multiple users using a single distributed feedback laser.

  12. T/R Multi-Chip MMIC Modules for 150 GHz

    Science.gov (United States)

    Samoska, Lorene A.; Pukala, David M.; Soria, Mary M.; Sadowy, Gregory A.

    2009-01-01

    Modules containing multiple monolithic microwave integrated-circuit (MMIC) chips have been built as prototypes of transmitting/receiving (T/R) modules for millimeter-wavelength radar systems, including phased-array radar systems to be used for diverse purposes that could include guidance and avoidance of hazards for landing spacecraft, imaging systems for detecting hidden weapons, and hazard-avoidance systems for automobiles. Whereas prior landing radar systems have operated at frequencies around 35 GHz, the integrated circuits in this module operate in a frequency band centered at about 150 GHz. The higher frequency (and, hence, shorter wavelength), is expected to make it possible to obtain finer spatial resolution while also using smaller antennas and thereby reducing the sizes and masses of the affected systems.

  13. 47 CFR 101.505 - Frequencies.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Frequencies. 101.505 Section 101.505 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.505 Frequencies. Frequencies, and...

  14. Towards the Realization of Graphene Based Flexible Radio Frequency Receiver

    Directory of Open Access Journals (Sweden)

    Maruthi N. Yogeesh

    2015-11-01

    Full Text Available We report on our progress and development of high speed flexible graphene field effect transistors (GFETs with high electron and hole mobilities (~3000 cm2/V·s, and intrinsic transit frequency in the microwave GHz regime. We also describe the design and fabrication of flexible graphene based radio frequency system. This RF communication system consists of graphite patch antenna at 2.4 GHz, graphene based frequency translation block (frequency doubler and AM demodulator and graphene speaker. The communication blocks are utilized to demonstrate graphene based amplitude modulated (AM radio receiver operating at 2.4 GHz.

  15. Radio continuum of galaxies with H2O megamaser disks: 33 GHz VLA data

    Science.gov (United States)

    Kamali, F.; Henkel, C.; Brunthaler, A.; Impellizzeri, C. M. V.; Menten, K. M.; Braatz, J. A.; Greene, J. E.; Reid, M. J.; Condon, J. J.; Lo, K. Y.; Kuo, C. Y.; Litzinger, E.; Kadler, M.

    2017-09-01

    Context. Galaxies with H2O megamaser disks are active galaxies in whose edge-on accretion disks 22 GHz H2O maser emission has been detected. Because their geometry is known, they provide a unique view into the properties of active galactic nuclei. Aims: The goal of this work is to investigate the nuclear environment of galaxies with H2O maser disks and to relate the maser and host galaxy properties to those of the radio continuum emission of the galaxy. Methods: The 33 GHz (9 mm) radio continuum properties of 24 galaxies with reported 22 GHz H2O maser emission from their disks are studied in the context of the multiwavelength view of these sources. The 29-37 GHz Ka-band observations are made with the Karl Jansky Very Large Array in B, CnB, or BnA configurations, achieving a resolution of 0.2-0.5 arcsec. Hard X-ray data from the Swift/BAT survey and 22 μm infrared data from WISE, 22 GHz H2O maser data and 1.4 GHz data from NVSS and FIRST surveys are also included in the analysis. Results: Eighty-seven percent (21 out of 24) galaxies in our sample show 33 GHz radio continuum emission at levels of 4.5-240σ. Five sources show extended emission (deconvolved source size larger than 2.5 times the major axis of the beam), including one source with two main components and one with three main components. The remaining detected 16 sources (and also some of the above-mentioned targets) exhibit compact cores within the sensitivity limits. Little evidence is found for extended jets (>300 pc) in most sources. Either they do not exist, or our chosen frequency of 33 GHz is too high for a detection of these supposedly steep spectrum features. In NGC 4388, we find an extended jet-like feature that appears to be oriented perpendicular to the H2O megamaser disk. NGC 2273 is another candidate whose radio continuum source might be elongated perpendicular to the maser disk. Smaller 100-300 pc sized jets might also be present, as is suggested by the beam-deconvolved morphology of our

  16. 0.8-5.2GHz Broad-Band SiGe-MMIC Quadrature Mixer for Software Defined Radio Receiver

    Science.gov (United States)

    Murakami, Keishi; Suematsu, Noriharu; Tsutsumi, Koji; Kanazawa, Gakushi; Sekine, Tomotsugu; Kubo, Hiroshi; Isota, Yoji

    For the next generation wireless terminals used in the software defined radio (SDR), multi-band / multi-mode transceivers and their MMIC are required which cover the wide RF frequency range from several hundreds MHz up to several GHz. In this paper, 0.8-5.2GHz broad-band SiGe-MMIC quadrature mixer (Q-MIX) for multi-band / multi-mode direct conversion receiver has been developed. By using a static type frequency divider as a 90 degrees local (LO) power divider, measured error vector magnitude (EVM) of less than 3.1% can be achieved in the cases of 0.8/2.1GHz W-CDMA and 5.2GHz wireless Local Area Network (LAN) (IEEE 802.11a) reception. This Q-MIX also shows broad-band characteristic for base-band signal and is applicable for 4G cellular. By using fabricated Q-MIX, a multi-band / multi-mode (1.9GHz (3rd generation cellular (W-CDMA)) / 5.2GHz (4th generation cellular (Multi-Carrier (MC)-CDMA))) receiver has been developed and it has firstly demonstrated the successful reception of motion picture via W-CDMA and MC-CDMA.

  17. The Fan Region at 1.5 GHz - I. Polarized synchrotron emission extending beyond the Perseus Arm

    Science.gov (United States)

    Hill, A. S.; Landecker, T. L.; Carretti, E.; Douglas, K.; Sun, X. H.; Gaensler, B. M.; Mao, S. A.; McClure-Griffiths, N. M.; Reich, W.; Wolleben, M.; Dickey, J. M.; Gray, A. D.; Haverkorn, M.; Leahy, J. P.; Schnitzeler, D. H. F. M.

    2017-06-01

    The Fan Region is one of the dominant features in the polarized radio sky, long thought to be a local (distance ≲500 pc) synchrotron feature. We present 1.3-1.8 GHz polarized radio continuum observations of the region from the Global Magneto-Ionic Medium Survey and compare them to maps of Hα and polarized radio continuum intensity from 0.408 to 353 GHz. The high-frequency (>1 GHz) and low-frequency (≲600 MHz) emissions have different morphologies, suggesting a different physical origin. Portions of the 1.5 GHz Fan Region emission are depolarized by ≈30 per cent by ionized gas structures in the Perseus Arm, indicating that this fraction of the emission originates ≳2 kpc away. We argue for the same conclusion based on the high polarization fraction at 1.5 GHz (≈40 per cent). The Fan Region is offset with respect to the Galactic plane, covering -5° ≲ b ≲ +10°; we attribute this offset to the warp in the outer Galaxy. We discuss origins of the polarized emission, including the spiral Galactic magnetic field. This idea is a plausible contributing factor although no model to date readily reproduces all of the observations. We conclude that models of the Galactic magnetic field should account for the ≳1 GHz emission from the Fan Region as a Galactic scale, not purely local, feature.

  18. Polarimetric monopulse radar scattering measurements of targets at 95 GHz

    Science.gov (United States)

    Wellman, R. J.; Nemarich, J.; Dropkin, H.; Hutchins, D. R.; Silvious, J. L.; Wikner, D. A.

    1991-09-01

    This paper describes a 95-GHz polarimetric monopulse instrumentation radar and selected scattering measurement results for an armored vehicle. The radar is all-solid-state, coherent, frequency steppable over a 640-MHz bandwidth, and completely polarimetric for linearly or circularly polarized radiation. Details of the methods used to perform the amplitude and phase calibrations and the effectiveness of polarization distortion matrix corrections are included in the paper. Measurements made with the radar of various vehicles on a turntable have allowed quasi-three-dimensional polarimetric ISAR images of the targets to be generated. Sample images for an infantry combat vehicle are presented together with high-resolution range profiles of the target for all monopulse channels.

  19. Development of 2.8-GHz Solar Flux Receivers

    Science.gov (United States)

    Yun, Youngjoo; Park, Yong-Sun; Kim, Chang-Hee; Lee, Bangwon; Kim, Jung-Hoon; Yoo, Saeho; Lee, Chul-Hwan; Han, Jinwook; Kim, Young Yun

    2014-12-01

    We report the development of solar flux receivers operating at 2.8 GHz to monitor solar radio activity. Radio waves from the sun are amplified, filtered, and then transmitted to a power meter sensor without frequency down-conversion. To measure solar flux, a calibration scheme is designed with a noise source, an ambient load, and a hot load at 100° C. The receiver is attached to a 1.8 m parabolic antenna in Icheon, owned by National Radio Research Agency, and observation is being conducted during day time on a daily basis. We compare the solar fluxes measured for last seven months with solar fluxes obtained by DRAO in Penticton, Canada, and by the Hiraiso solar observatory in Japan, and finally establish equations to convert observed flux to the so-called Penticton flux with an accuracy better than 3.2 sfu.

  20. Feasibility studies for a wireless 60 GHz tracking detector readout

    CERN Document Server

    Dittmeier, Sebastian; Soltveit, Hans Kristian; Wiedner, Dirk

    2016-01-01

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the in...

  1. Planck 2015 results: VII. High Frequency Instrument data processing: Time-ordered information and beams

    DEFF Research Database (Denmark)

    Adam, R.; Ade, P. A R; Aghanim, N.

    2016-01-01

    The Planck High Frequency Instrument (HFI) has observed the full sky at six frequencies (100, 143, 217, 353, 545, and 857 GHz) in intensity and at four frequencies in linear polarization (100, 143, 217, and 353 GHz). In order to obtain sky maps, the time-ordered information (TOI) containing...

  2. Integrated 222-GHz corner-reflector antennas

    Science.gov (United States)

    Gearhart, Steven S.; Ling, Curtis C.; Rebeiz, Gabriel M.

    1991-01-01

    A high-gain monolithic millimeter-wave antenna has been designed, fabricated, and tested at 222 GHz. The structure consists of a traveling-wave antenna integrated on a 1.2-micron dielectric membrane and suspended in a longitudinal cavity etched in a silicon wafer. A new traveling-wave antenna design yields a wideband input impedance and a low cross-polarization component in the E- and quasi-H-plane patterns. A directivity of 17.7 dB and a main-beam efficiency of 88.5 percent are calculated from the 222-GHz pattern measurements. The integrated corner-reflector antenna is well suited for millimeter- and submillimeter-wave imaging applications in large f-number systems.

  3. Multiple teleportation via partially entangled GHZ state

    Science.gov (United States)

    Xiong, Pei-Ying; Yu, Xu-Tao; Zhan, Hai-Tao; Zhang, Zai-Chen

    2016-08-01

    Quantum teleportation is important for quantum communication. We propose a protocol that uses a partially entangled Greenberger-Horne-Zeilinger (GHZ) state for single hop teleportation. Quantum teleportation will succeed if the sender makes a Bell state measurement, and the receiver performs the Hadamard gate operation, applies appropriate Pauli operators, introduces an auxiliary particle, and applies the corresponding unitary matrix to recover the transmitted state.We also present a protocol to realize multiple teleportation of partially entangled GHZ state without an auxiliary particle. We show that the success probability of the teleportation is always 0 when the number of teleportations is odd. In order to improve the success probability of a multihop, we introduce the method used in our single hop teleportation, thus proposing a multiple teleportation protocol using auxiliary particles and a unitary matrix. The final success probability is shown to be improved significantly for the method without auxiliary particles for both an odd or even number of teleportations.

  4. 120-GHz HEMT Oscillator With Surface-Wave-Assisted Antenna

    Science.gov (United States)

    Samoska, Lorene; Siegel, Peter; Leong, Kevin; Itoh, Tatsuo; Qian, Yongxi; Radisic, Vesna

    2003-01-01

    Two monolithic microwave integrated circuits (MMICs) have been designed and built to function together as a source of electromagnetic radiation at a frequency of 120 GHz. One of the MMICs is an oscillator and is the highest-power 120-GHz oscillator reported thus far in the literature. The other MMIC is an end-fire antenna that radiates the oscillator signal. Although these MMICs were constructed as separate units and electrically connected with wire bonds, future oscillator/ antenna combinations could readily be fabricated as monolithic integrated units. Such units could be used as relatively high-power solid-state microwave sources in diverse applications that include automotive radar, imaging, scientific instrumentation, communications, and radio astronomy. As such, these units would be attractive alternatives to vacuum-tube oscillators, which are still used to obtain acceptably high power in the frequency range of interest. The oscillator (see figure) includes a high-electron-mobility transistor (HEMT), with gate-periphery dimensions of 4 by 37 m, in a common-source configuration. The series feedback element of the oscillator is a grounded coplanar waveguide (CPW) at the source. The HEMT is biased for class-A operation (meaning that current is conducted throughout the oscillation cycle) to maximize the output power of the oscillator. Input and output impedance-matching circuit elements are designed to maximize output power and to establish the conditions needed for oscillation. The design of the antenna takes advantage of surface waves, which, heretofore, have been regarded as highly disadvantageous because they can leak power and degrade the performances of antennas that have not been designed to exploit them. Measures taken to suppress surface waves have included complex machining of circuit substrates and addition of separate substrates. These measures are difficult to implement in standard MMIC fabrication processes. In contrast, because the design of the

  5. Simultaneous measurements of atmospheric emissions at 10, 33 and 90 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Costales, J.B.

    1984-11-01

    As part of a larger experiment to measure the cosmic microwave background radiation spectrum, frequent simultaneous measurements of the microwave thermal emission from the earth's atmosphere were made at three fixed frequencies, namely, 10 GHz, 33 GHz and 90 GHz. We performed these measurements at two separate locations, Berkeley and White Mountain, which greatly differed in altitude and climatic conditions. Typical values measured in Berkeley of the atmospheric antenna temperature during good weather are 3.13 +- 0.30/sup 0/K, 12.3 +- 0.3/sup 0/K and 34.6 +- 0.5/sup 0/K, for 10, 33, and 90 GHz respectively. Corresponding values measured at White Mountain are 1.15 +- 0.1/sup 0/K, 4.51 +- 0.18/sup 0/K and 11.0 +- 0.2/sup 0/K. Because the measurements are simultaneous in nature, correlations between the measurements taken at the various frequencies provide constraints on models of the microwave emission of the earth's atmosphere, especially models describing atmospheric emission as a function of precipitable water content.

  6. A 94-GHz Millimeter-Wave Sensor for Speech Signal Acquisition

    Directory of Open Access Journals (Sweden)

    Jianqi Wang

    2013-10-01

    Full Text Available High frequency millimeter-wave (MMW radar-like sensors enable the detection of speech signals. This novel non-acoustic speech detection method has some special advantages not offered by traditional microphones, such as preventing strong-acoustic interference, high directional sensitivity with penetration, and long detection distance. A 94-GHz MMW radar sensor was employed in this study to test its speech acquisition ability. A 34-GHz zero intermediate frequency radar, a 34-GHz superheterodyne radar, and a microphone were also used for comparison purposes. A short-time phase-spectrum-compensation algorithm was used to enhance the detected speech. The results reveal that the 94-GHz radar sensor showed the highest sensitivity and obtained the highest speech quality subjective measurement score. This result suggests that the MMW radar sensor has better performance than a traditional microphone in terms of speech detection for detection distances longer than 1 m. As a substitute for the traditional speech acquisition method, this novel speech acquisition method demonstrates a large potential for many speech related applications.

  7. Atacama Cosmology Telescope: Extragalactic Sources at 148 GHz in the 2008 Survey

    CERN Document Server

    Marriage, T A; Lin, Y -T; Marsden, D; Nolta, M R; Partridge, B; Ade, P A R; Aguirre, P; Amiri, M; Appel, J W; Barrientos, L F; Battistelli, E S; Bond, J R; Brown, B; Burger, B; Chervenak, J; Das, S; Devlin, M J; Dicker, S R; Doriese, W B; Dunkley, J; Dunner, R; Essinger-Hileman, T; Fisher, R P; Fowler, J W; Hajian, A; Halpern, M; Hasselfield, M; Hernandez-Monteagudo, C; Hilton, G C; Hilton, M; Hincks, A D; Hlozek, R; Huffenberger, K M; Hughes, D H; Hughes, J P; Infante, L; Irwin, K D; Kaul, M; Klein, J; Kosowsky, A; Lau, J M; Limon, M; Lupton, R H; Martocci, K; Mauskopf, P; Menanteau, F; Moodley, K; Moseley, H; Netterfield, C B; Niemack, M D; Page, L A; Parker, L; Quintana, H; Reid, B; Sehgal, N; Sherwin, B D; Sievers, J; Spergel, D N; Staggs, S T; Swetz, D S; Switzer, E R; Thornton, R; Trac, H; Tucker, C; Warne, R; Wilson, G; Wollack, E; Zhao, Y

    2010-01-01

    We report on extragalactic sources detected in a 455 square-degree map of the southern sky made with data at a frequency of 148 GHz from the Atacama Cosmology Telescope 2008 observing season. We provide a catalog of 157 sources with flux densities spanning two orders of magnitude: from 15 to 1500 mJy. Comparison to other catalogs shows that 98% of the ACT detections correspond to sources detected at lower radio frequencies. Three of the sources appear to be associated with the brightest cluster galaxies of low redshift X-ray selected galaxy clusters. Estimates of the radio to mm-wave spectral indices and differential counts of the sources further bolster the hypothesis that they are nearly all radio sources, and that their emission is not dominated by re-emission from warm dust. In a bright (>50 mJy) 148 GHz-selected sample with complete cross-identifications from the Australia Telescope 20 GHz survey, we observe an average steepening of the spectra between 5, 20, and 148 GHz with median spectral indices of $...

  8. Flare SOL2012-07-06: On the Origin of the Circular Polarization Reversal Between 17 GHz and 34 GHz

    Science.gov (United States)

    Altyntsev, A.; Meshalkina, N.; Myshyakov, I.; Pal`shin, V.; Fleishman, G.

    2017-09-01

    The new generation of multiwavelength radioheliographs with high spatial resolution will employ microwave imaging spectropolarimetry to recover flare topology and plasma parameters in the flare sources and along the wave propagation paths. The recorded polarization depends on the emission mechanism and emission regime (optically thick or thin), the emitting particle properties, and propagation effects. Here, we report an unusual flare, SOL2012-07-06T01:37, whose optically thin gyrosynchrotron emission of the main source displays an apparently ordinary mode sense of polarization in contrast to the classical theory that favors the extraordinary mode. This flare produced copious nonthermal emission in hard X-rays and in high-frequency microwaves up to 80 GHz. It is found that the main flare source corresponds to an interaction site of two loops with greatly different sizes. The flare occurred in the central part of the solar disk, which allows reconstructing the magnetic field in the flare region using vector magnetogram data. We have investigated the three possible known reasons of the circular polarization sense reversal - mode coupling, positron contribution, and the effect of beamed angular distribution. We excluded polarization reversal due to contribution of positrons because there was no relevant response in the X-ray emission. We find that a beam-like electron distribution can produce the observed polarization behavior, but the source thermal density must be much higher than the estimate from to the X-ray data. We conclude that the apparent ordinary wave emission in the optically thin mode is due to radio wave propagation across the quasi-transverse (QT) layer. The abnormally high transition frequency (above 35 GHz) can be achieved reasonably low in the corona where the magnetic field value is high and transverse to the line of sight. This places the microwave source below this QT layer, i.e. very low in the corona.

  9. TFTR 60 GHz alpha particle collective Thomson Scattering diagnostic

    Energy Technology Data Exchange (ETDEWEB)

    Machuzak, J.S.; Woskov, P.P.; Gilmore, J. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Bretz, N.L.; Park, H.K. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Aamodt, R.E.; Cheung, P.Y.; Russell, D.A. [Lodestar Research Corp., Boulder, CO (United States); Bindslev, H. [JET Joint Undertaking, Abingdon (United Kingdom)

    1995-03-01

    A 60 GHz gyrotron collective Thomson Scattering alpha particle diagnostic has been implemented for the D-T period on TFM. Gyrotron power of 0.1-1 kW in pulses of up to 1 second can be launched in X-mode. Efficient corrugated waveguides are used with antennaes and vacuum windows of the TFTR Microwave Scattering system. A multichannel synchronous detector receiver system and spectrum analyzer acquire the scattered signals. A 200 Megasample/sec digitizer is used to resolve fine structure in the frequency spectrum. By scattering nearly perpendicular to the magnetic field, this experiment will take advantage of an enhancement of the scattered signal which results from the interaction of the alpha particles with plasma resonances in the lower hybrid frequency range. Significant enhancements are expected, which will make these measurements possible with gyrotron power less than 1 kW, while maintaining an acceptable signal to noise ratio. We hope to extract alpha particle density and velocity distribution functions from the data. The D and T fuel densities and temperatures may also be obtainable by measurement of the respective ion cyclotron harmonic frequencies.

  10. A 6.5-GHz Multibeam Pulsar Survey

    CERN Document Server

    Bates, S D; Lorimer, D R; Kramer, M; Possenti, A; Burgay, M; Stappers, B; Keith, M J; Lyne, A; Bailes, M; McLaughlin, M A; O'Brien, J T; Hobbs, G

    2010-01-01

    A survey of the Galactic plane in the region $-60\\degree \\leq l \\leq 30\\degree$, $|b| \\leq 0.25\\degree$ was carried out using the seven-beam Parkes Methanol Multibeam (MMB) receiver, which operates at a frequency of 6.5 GHz. Three pulsars were discovered, and 16 previously known pulsars detected. In this paper we present two previously-unpublished discoveries, both with extremely high dispersion measures, one of which is very close, in angular distance, to the Galactic centre. The survey data also contain the first known detection, at radio frequencies, of the radio magnetar PSR J1550-5418. Our survey observation was made 46 days prior to that previously published and places constraints on the beginning of pulsed radio emission from the source. The detection of only three previously undiscovered pulsars argues that there are few pulsars in the direction of the inner Galaxy whose flux density spectrum is governed by a flat power law. However, these pulsars would be likely to remain undetected at lower frequenc...

  11. The 6.7-GHz and 25-GHz methanol masers in OMC-1

    CERN Document Server

    Voronkov, M A; Ellingsen, S P; Ostrovskii, A B

    2005-01-01

    The Australia Telescope Compact Array (ATCA) has been used to search for methanol maser emission at 6.7 GHz towards OMC-1. Two features peaking at 7.2 km/s and -1.1 km/s have been detected. The former has at least two components close in both velocity and position. It is located south-east of the Orion Kleinmann-Low (Orion-KL) nebula in the region of outflow traced by the 25-GHz methanol masers and the 95-GHz methanol emission. It is shown by modelling that in contrast to the widespread opinion that simultaneous masing of methanol transitions of different classes is impossible there are conditions for which simultaneous masing of the class II transition at 6.7-GHz and some class I transitions (e.g. the series at 25 GHz) is possible. A relevant example is provided, in which the pumping occurs via the first torsionally excited state and is driven by radiation of the dust intermixed with the gas in the cloud. In this regime the dust temperature is significantly lower (T is about 60 K) than in the case of bright ...

  12. Modeling, design, fabrication, and testing of InP Gunn devices in the D-band (110 GHz - 170 GHz)

    Science.gov (United States)

    Kamoua, R.; Eisele, H.; East, J. R.; Haddad, G. I.; Munns, G.; Sherwin, M.

    1992-01-01

    The development of fundamental Gunn sources for D-band frequencies requires improvements of doping profiles, processing technology, and circuit design. We have developed a technology for fabricating InP Gunn diodes using an InGaAs etch-stop layer between the InP substrate and the device layers. The epitaxial layers were grown by CBE. During device processing, the substrate is completely removed. Substrateless devices with an n(+) InGaAs cap layer are expected to have reduced contact and series resistances, and skin effect losses. This technology gives better uniformity and control of the device geometry across the processed chip. InP Gunn devices with a 1.7 micron long active region (doping : 9 x 10(exp 15) cm(exp -3)) have been mounted on copper heat sinks. Two tapered leads were then bonded to the diode and to four quartz standoffs. As a preliminary result, an output power of 13 mW at 82 GHz was obtained. Based on these RF measurements, we determine appropriate material parameters to be used in the Ensemble Monte Carlo model. Subsequently, we use this model to design and evaluate the performance of InP Gunn Devices for D-band frequencies. Using the same technology, we are currently processing Gunn devices with a 1 micron long active region for operation at higher frequencies.

  13. Observation of harmonic gyro-backward-wave oscillation in a 100 GHz CARM oscillator experiment

    Science.gov (United States)

    McCowan, Robert B.; Sullivan, Carol A.; Gold, Steven H.; Fliflet, Arne W.

    1991-02-01

    A cyclotron autoresonance maser (CARM) oscillator experiment is reported, using a 600 keV, 200 A electron beam, and a whispering gallery-mode rippled-wall Bragg cavity. This device was designed to produce tens of megawatts of radiation at 100 GHz from a CARM interaction, but instead has produced only moderate powers (tens of kWs) in fundamental gyrotron modes near 35 GHz, in third-harmonic-gyro-BWO modes, and possible third-harmonic gyrotron modes at frequencies near the expected CARM frequency, with no discernable CARM radiation. The lack of observable CARM radiation is attributed to excessive ripple on the voltage waveform and to mode competition. Calculations of the spectrum and growth rate of the backward-wave oscillations are consistent with the experimental observation.

  14. 60-GHz integrated-circuit high data rate quadriphase shift keying exciter and modulator

    Science.gov (United States)

    Grote, A.; Chang, K.

    1984-01-01

    An integrated-circuit quadriphase shift keying (QPSK) exciter and modulator have demonstrated excellent performance directly modulating a carrier frequency of 60 GHz with an output phase error of less than 3 degrees and maximum amplitude error of 0.5 dB. The circuit consists of a 60-GHz Gunn VCO phase-locked to a low-frequency reference source, a 4th subharmonic mixer, and a QPSK modlator packaged into a small volume of 1.8 x 2.5 x 0.35 in. The use of microstrip has the advantages of small size, light-weight, and low-cost fabrication. The unit has the potential for multigigabit data rate applications.

  15. A Compact 5.5 GHz Band-Rejected UWB Antenna Using Complementary Split Ring Resonators

    Directory of Open Access Journals (Sweden)

    M. M. Islam

    2014-01-01

    Full Text Available A band-removal property employing microwave frequencies using complementary split ring resonators (CSRRs is applied to design a compact UWB antenna wishing for the rejection of some frequency band, which is meanwhile exercised by the existing wireless applications. The reported antenna comprises optimization of a circular radiating patch, in which slotted complementary SRRs are implanted. It is printed on low dielectric FR4 substrate material fed by a partial ground plane and a microstrip line. Validated results exhibit that the reported antenna shows a wide bandwidth covering from 3.45 to more than 12 GHz, with a compact dimension of 22 × 26 mm2, and VSWR < 2, observing band elimination of 5.5 GHz WLAN band.

  16. Time-Resolved Cavity Nano-Optomechanics in the 20-100 GHz range

    CERN Document Server

    Anguiano, S; Jusserand, B; Favero, I; Lamperti, F R; Lanco, L; Sagnes, I; Lemaître, A; Lanzillotti-Kimura, N D; Senellart, P; Fainstein, A

    2016-01-01

    Applications of cavity optomechanics span from gravitational wave detection to the study of quantum motion states in mesoscopic mechanical systems. The engineering of resonators supporting strongly interacting mechanical and optical modes is central to these developments. However, current technological and experimental approaches limit the accessible mechanical frequencies to a few GHz, imposing hard constraints on quantum mechanical studies. Here we demonstrate the optical control of 20-100~GHz mechanical modes confined in the three dimensions within semiconductor nano-optomechanical pillar cavities. We use a time-resolved transient optical reflectivity technique and access both the energy spectrum and dynamics of the mechanical modes at the picosecond timescale. A strong increase of the optomechanical coupling upon reducing the pillar size is observed together with unprecedent room temperature Q-frequency products above $10^{14}$. The measurements also reveal sideband generation in the optomechanical respon...

  17. Realization of a 33 GHz phononic crystal fabricated in a freestanding membrane

    Directory of Open Access Journals (Sweden)

    Drew F. Goettler

    2011-12-01

    Full Text Available Phononic crystals (PnCs are man-made structures with periodically varying material properties such as density, ρ, and elastic modulus, E. Periodic variations of the material properties with nanoscale characteristic dimensions yield PnCs that operate at frequencies above 10 GHz, allowing for the manipulation of thermal properties. In this article, a 2D simple cubic lattice PnC operating at 33 GHz is reported. The PnC is created by nanofabrication with a focused ion beam. A freestanding membrane of silicon is ion milled to create a simple cubic array of 32 nm diameter holes that are subsequently backfilled with tungsten to create inclusions at a spacing of 100 nm. Simulations are used to predict the operating frequency of the PnC. Additional modeling shows that milling a freestanding membrane has a unique characteristic; the exit via has a conical shape, or trumpet-like appearance.

  18. Development of 460 GHz and Dual Polarization SIS Mixers for the Submillimeter Array

    Science.gov (United States)

    Li, Chao-Te; Liu, Kuan-Yu; Lu, Wei-Chun; Chiu, Chuang-Ping; Chen, Tse-Jun; Chen, Chong-Wen; Chang, Yung-Chin; Wang, Ming-Jye; Shi, Sheng-Cai

    2011-06-01

    A heterodyne receiver incorporating superconductor-insulator- superconductor (SIS) mixers has been designed to cover the frequency range from 400 to 520 GHz of the Submillimeter Array (SMA). Various tuning circuits have been employed to resonate out the geometric capacitance of the junction and provide impedance matching to the waveguide probe. Our measurements indicated that a receiver noise temperature of around 90 K, with the contributions from the input noise and intermediate frequency (IF) noise estimated to be around 60 K and 10 K, respectively. SIS mixers integrated with planar orthomode transducers (OMT) have also been designed at 345 GHz for dual polarization detections, and results from the 3-dimensional (3-D) electromagnetic (EM) simulations are presented.

  19. A 6-9 GHz 5-band CMOS synthesizer for MB-OFDM UWB

    Energy Technology Data Exchange (ETDEWEB)

    Chen Pufeng; Li Zhiqiang; Wang Xiaosong; Zhang Haiying; Ye Tianchun, E-mail: chenpufeng@ime.ac.c [Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029 (China)

    2010-07-15

    An ultra-wideband frequency synthesizer is designed to generate carrier frequencies for 5 bands distributed from 6 to 9 GHz with less than 3 ns switching time. It incorporates two phase-locked loops and one single-sideband (SSB) mixer. A 2-to-1 multiplexer with high linearity is proposed. A modified wideband SSB mixer, quadrature VCO, and layout techniques are also employed. The synthesizer is fabricated in a 0.18 {mu}m CMOS process and operates at 1.5-1.8 V while consuming 40 mA current. The measured phase noise is -128 dBc/Hz at 10 MHz offset, and the sideband rejection is -22 dBc at 7.656 GHz.

  20. Rayleigh scattering boosted multi-GHz displacement sensitivity in whispering gallery opto-mechanical resonators

    CERN Document Server

    Tallur, Siddharth

    2013-01-01

    Finite photon lifetimes for light fields in an opto-mechanical cavity impose a bandwidth limit on displacement sensing at mechanical resonance frequencies beyond the loaded cavity photon decay rate. Opto-mechanical modulation efficiency can be enhanced via multi-GHz transduction techniques such as piezo-opto-mechanics at the cost of on-chip integration. In this paper, we present a novel high bandwidth displacement sense scheme employing Rayleigh scattering in photonic resonators. Using this technique in conjunction with on-chip electrostatic drive in silicon enables efficient modulation at frequencies up to 9.1GHz. Being independent of the drive mechanism, this scheme could readily be extended to piezo-opto-mechanical and all optical transduced systems.

  1. Design of energy conscious antenna system for WLAN frequency band

    CSIR Research Space (South Africa)

    Bembe, MJ

    2009-08-01

    Full Text Available loading the parasitic elements. These imply the achievement of low power antenna system with low fabrication cost. The ESPAR antenna can be designed to cover the frequency bands of the wireless local area network (WLAN), which are 2.4GHz and 5.8GHz...

  2. THE GBT 67–93.6 GHz SPECTRAL LINE SURVEY OF ORION-KL

    Energy Technology Data Exchange (ETDEWEB)

    Frayer, D. T.; Maddalena, Ronald J.; Meijer, M.; Hough, L.; White, S.; Norrod, R.; Watts, G.; Stennes, M.; Simon, R.; Woody, D.; Whitehead, M.; Ford, P.; Mello, M.; Bloss, M. [National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944 (United States); Srikanth, S.; Pospieszalski, M.; Bryerton, E. [National Radio Astronomy Observatory Central Development Lab, 1180 Boxwood Estate Road, Charlottesville, VA 22903 (United States)

    2015-05-15

    We present a 67–93.6 GHz spectral line survey of Orion-KL with the new 4 mm Receiver on the Green Bank Telescope (GBT). The survey reaches unprecedented depths and covers the low-frequency end of the 3 mm atmospheric window which has been relatively unexplored previously. The entire spectral-line survey is published electronically for general use by the astronomical community. The calibration and performance of the 4 mm Receiver on the GBT is also summarized.

  3. The GBT 67 -- 93.6 GHz Spectral Line Survey of Orion-KL

    CERN Document Server

    Frayer, D T; Meijer, M; Hough, L; White, S; Norrod, R; Watts, G; Stennes, M; Simon, R; Woody, D; Srikanth, S; Pospieszalski, M; Bryerton, E; Whitehead, M; Ford, P; Mello, M; Bloss, M

    2015-01-01

    We present a 67--93.6 GHz spectral line survey of Orion-KL with the new 4 mm Receiver on the Green Bank Telescope (GBT). The survey reaches unprecedented depths and covers the low-frequency end of the 3 mm atmospheric window which has been relatively unexplored previously. The entire spectral-line survey is published electronically for general use by the astronomical community. The calibration and performance of 4 mm Receiver on the GBT is also summarized.

  4. Detection of the 610 micron /492 GHz/ line of interstellar atomic carbon

    Science.gov (United States)

    Phillips, T. G.; Huggins, P. J.; Kuiper, T. B. H.; Miller, R. E.

    1980-01-01

    The ground-state transition of neutral atomic carbon, 3P1-3P0, has been detected in the interstellar medium at the frequency of 492.162 GHz determined in the laboratory by Saykally and Evenson (1980). The observations were made from the NASA Kuiper Airborne Observatory using an InSb heterodyne bolometer receiver. The line was detected as strong emission from eight molecular clouds and apparently provides a widely useful probe of the interstellar medium.

  5. CTS attenuation and cross-polarization measurements at 11.7 GHz

    Science.gov (United States)

    Vogel, W. J.; Straiton, A. W.

    1977-01-01

    The results of data obtained 80 days preceding the solar eclipse shutdown of the CTS 11.7 GHz righthand circularly polarized beacon transmitter are presented. Attenuation and cross polarization isolation were measured. It was determined that depolarization presents a serious limitation to satellite system reliability when frequency reuse by polarization diversity is employed. A 27 db isolation margin would reduce reliability below 99.95%. For the same percentage the required fade margin was below 3 db.

  6. 10GHz Demonstration of Four-Wave-Mixing in Photonic Crystal Waveguides

    OpenAIRE

    Lengle K.; Akrout A.; Costa E Silva M.; Bramerie L.; Combrie S.; Colman P.; Simon J.-C.; Rossi A.

    2010-01-01

    International audience; We report time resolved measurement of the nonlinear frequency conversion of a high repetition rate (10 GHz) train of short pulses (up to 4 ps) in a 1.5 mm long Photonic Crystal waveguides. We provide direct evidence of fast response through time-resolved optical measurements. The conversion gain of about -40dB is achieved with about 60 mW of average power at the waveguide input

  7. Q-Band (37-41 GHz) Satellite Beacon Architecture for RF Propagation Experiments

    Science.gov (United States)

    Simmons, Rainee N.; Wintucky, Edwin G.

    2012-01-01

    In this paper, the design of a beacon transmitter that will be flown as a hosted payload on a geostationary satellite to enable propagation experiments at Q-band (37-41 GHz) frequencies is presented. The beacon uses a phased locked loop stabilized dielectric resonator oscillator and a solid-state power amplifier to achieve the desired output power. The satellite beacon antenna is configured as an offset-fed cut-paraboloidal reflector.

  8. Q-Band (37 to 41 GHz) Satellite Beacon Architecture for RF Propagation Experiments

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.

    2014-01-01

    In this paper, the design of a beacon transmitter that will be flown as a hosted payload on a geostationary satellite to enable propagation experiments at Q-band (37 to 41 GHz) frequencies is presented. The beacon uses a phased locked loop stabilized dielectric resonator oscillator and a solid-state power amplifier to achieve the desired output power. The satellite beacon antenna is configured as an offset-fed cutparaboloidal reflector.

  9. Development of a Wideband Compact Orthomode Transducer for the 180-270 GHz Band

    Science.gov (United States)

    Leal-Sevillano, Carlos A.; Reck, Theodore J.; Chattopadhyay, Goutam; Ruiz-Cruz, Jorge A.; Montejo-Garai, Jose R.; Rebollar, Jesus M.

    2014-09-01

    In this paper, we report the development of a wideband compact orthomode transducer (OMT) for the 180-270 GHz band. The OMT design is based on the classical high performance Bøifot waveguide junction and implemented in split-block using high precision CNC milling. The obtained results validate the high performance operation in a 40% fractional bandwidth and constitute a remarkable achievement at this high frequency band.

  10. Deep Source-Counting at 3 GHz

    Science.gov (United States)

    Vernstrom, Tessa; Wall, Jasper; Scott, Douglas

    2014-05-01

    We describe an analysis of 3-GHz confusion-limited data from the Karl J. Jansky Very Large Array (VLA). We show that with minimal model assumptions, P(D), Bayesian and Markov-Chain Mone-Carlo (MCMC) methods can define the source count to levels some 10 times fainter than the conventional confusion limit. Our verification process includes a full realistic simulation that considers known information on source angular extent and clustering. It appears that careful analysis of the statistical properties of an image is more effective than counting individual objects.

  11. An LTCC 94 GHz Antenna Array

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre, J; Pao, H; Lin, H; Garland, P; O' Neill, D; Horton, K

    2007-12-21

    An antenna array is designed in low-temperature cofired ceramic (LTCC) Ferro A6M{trademark} for a mm-wave application. The antenna is designed to operate at 94 GHz with a few percent bandwidth. A key manufacturing technology is the use of 3 mil diameter vias on a 6 mil pitch to construct the laminated waveguides that form the beamforming network and radiating elements. Measurements for loss in the laminated waveguide are presented. The slot-fed cavity-radiating element is designed to account for extremely tight mutual coupling between elements. The array incorporates a slot-fed multi-layer beamforming network.

  12. Dielectric Resonator Antenna Mounted on Cylindrical Ground Plane for Handheld RFID Reader at 5.8 GHz

    Directory of Open Access Journals (Sweden)

    Hend Abd El-Azem Malhat

    2012-10-01

    Full Text Available Dielectric resonator antenna (DRA mounted on cylindrical ground plane is investigated for handheld RFID reader applications at 5.8 GHz. The simplicity of the structure makes it practical in terms of cost, space, and ease of fabrication. The radiation characteristics of the antenna in free space and in the presence of a proposed compact reader device model and human hand are calculated. The antenna is circularly polarized and exhibits peak gain of 7.62 dB at 5.8 GHz with high front to back ratio of 15.5 dB. Using the same reader device model, a sequentially feeding 2×2 DRA array mounted on the same cylindrical ground plane is used for RFID reader antenna at 5.8 GHz. The array introduces high gain of 9.36 dB at 5.8 GHz with high front to back ratio of 10.48 dB. The 2×2 DRA array elements exhibit circular polarization over a frequency band of 1.1 GHz. The axial ratio is 1.1 dB at 5.8 GHz. The proposed reader model is simple and has a small size compared with that in the case of planar ground plane. The results are calculated using the finite element method (FEM and compared with that calculated using the finite integral technique (FIT.

  13. Summary and analysis of 216 GHz polarimetric measurements of in-situ rain

    Science.gov (United States)

    Hedden, Abigail S.; Wikner, David A.; Bradley, Russell W.

    2015-05-01

    The Army Research Laboratory (ARL) has developed a polarimetric frequency-modulated continuous-wave (FMCW) instrumentation radar that has been used to study the polarization and backscatter properties of in-situ rain in the 220 GHz atmospheric window. A summary of the preliminary measurements is presented in this work including an analysis of the co-polarization backscatter and attenuation characteristics measured at 216 GHz. A marginal detection of the copolarization backscatter signature of rain was made during a series of fast-moving, heavy downpour thunderstorm events. A detection limit of -40±3 dB[m2/m3] was found for the VV-polarization cross section per unit volume for rain rates up to 150 mm/hr. Co-polarization (VV- and HH-polarization) attenuation characteristics measured at high rain rates (< 20 mm/hr) were well described by a Joss thunderstorm drop distribution in the high frequency limit, where drop size is much greater than the observation wavelength. Observations at 216 GHz suggest attenuation levels of 8-10 dB/km at rain rates above 20 mm/hr, strengthening previous evidence that attenuation through rain is independent of frequency under high rain rate conditions. Attenuation measurements at lower rain rates (< 20 mm/hr) were qualitatively consistent with both Laws and Parsons and Joss thunderstorm distributions.

  14. Bi-layer Kinetic Inductance Detectors for space observations between 80-120 GHz

    CERN Document Server

    Catalano, A; Sueur, H le; Benoit, A; Bourrion, O; Calvo, M; Dumoulin, L; Levy-Bertrand, F; Macìas-Pérez, J; Marnieros, S; Ponthieu, N; Monfardini, A

    2015-01-01

    We have developed Lumped Element Kinetic Inductance Detectors (LEKID) sensitive in the frequency band from 80 to 120~GHz. In this work, we take advantage of the so-called proximity effect to reduce the superconducting gap of Aluminium, otherwise strongly suppressing the LEKID response for frequencies smaller than 100~GHz. We have designed, produced and optically tested various fully multiplexed arrays based on multi-layers combinations of Aluminium (Al) and Titanium (Ti). Their sensitivities have been measured using a dedicated closed-circle 100 mK dilution cryostat and a sky simulator allowing to reproduce realistic observation conditions. The spectral response has been characterised with a Martin-Puplett interferometer up to THz frequencies, and with a resolution of 3~GHz. We demonstrate that Ti-Al LEKID can reach an optical sensitivity of about $1.4$ $10^{-17}$~$W/Hz^{0.5}$ (best pixel), or $2.2$ $10^{-17}$~$W/Hz^{0.5}$ when averaged over the whole array. The optical background was set to roughly 0.4~pW pe...

  15. Microwave Frequency Multiplier

    Science.gov (United States)

    Velazco, J. E.

    2017-02-01

    High-power microwave radiation is used in the Deep Space Network (DSN) and Goldstone Solar System Radar (GSSR) for uplink communications with spacecraft and for monitoring asteroids and space debris, respectively. Intense X-band (7.1 to 8.6 GHz) microwave signals are produced for these applications via klystron and traveling-wave microwave vacuum tubes. In order to achieve higher data rate communications with spacecraft, the DSN is planning to gradually furnish several of its deep space stations with uplink systems that employ Ka-band (34-GHz) radiation. Also, the next generation of planetary radar, such as Ka-Band Objects Observation and Monitoring (KaBOOM), is considering frequencies in the Ka-band range (34 to 36 GHz) in order to achieve higher target resolution. Current commercial Ka-band sources are limited to power levels that range from hundreds of watts up to a kilowatt and, at the high-power end, tend to suffer from poor reliability. In either case, there is a clear need for stable Ka-band sources that can produce kilowatts of power with high reliability. In this article, we present a new concept for high-power, high-frequency generation (including Ka-band) that we refer to as the microwave frequency multiplier (MFM). The MFM is a two-cavity vacuum tube concept where low-frequency (2 to 8 GHz) power is fed into the input cavity to modulate and accelerate an electron beam. In the second cavity, the modulated electron beam excites and amplifies high-power microwaves at a frequency that is a multiple integer of the input cavity's frequency. Frequency multiplication factors in the 4 to 10 range are being considered for the current application, although higher multiplication factors are feasible. This novel beam-wave interaction allows the MFM to produce high-power, high-frequency radiation with high efficiency. A key feature of the MFM is that it uses significantly larger cavities than its klystron counterparts, thus greatly reducing power density and arcing

  16. High frequency nanotube oscillator

    Science.gov (United States)

    Peng, Haibing [Houston, TX; Zettl, Alexander K [Kensington, TX

    2012-02-21

    A tunable nanostructure such as a nanotube is used to make an electromechanical oscillator. The mechanically oscillating nanotube can be provided with inertial clamps in the form of metal beads. The metal beads serve to clamp the nanotube so that the fundamental resonance frequency is in the microwave range, i.e., greater than at least 1 GHz, and up to 4 GHz and beyond. An electric current can be run through the nanotube to cause the metal beads to move along the nanotube and changing the length of the intervening nanotube segments. The oscillator can operate at ambient temperature and in air without significant loss of resonance quality. The nanotube is can be fabricated in a semiconductor style process and the device can be provided with source, drain, and gate electrodes, which may be connected to appropriate circuitry for driving and measuring the oscillation. Novel driving and measuring circuits are also disclosed.

  17. A 311-GHz Fundamental Oscillator Using InP HBT Technology

    Science.gov (United States)

    Gaier, Todd; Fung, King Man; Samoska, Lorene; Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, W.R.

    2010-01-01

    This oscillator uses a single-emitter 0.3- m InP heterojunction bipolar transistor (HBT) device with maximum frequency of oscillation (fmax) greater than 500 GHz. Due to high conductor and substrate losses at submillimeterwave frequencies, a primary challenge is to efficiently use the intrinsic device gain. This was done by using a suitable transmission-line media and circuit topology. The passive components of the oscillator are realized in a twometal process with benzocyclobutene (BCB) used as the primary transmission line dielectric. The circuit was designed using microstrip transmission lines. The oscillator is implemented in a common-base topology due to its inherent instability, and the design includes an on-chip resonator, outputmatching circuitry, and an injection-locking port, the port being used to demonstrate the injection-locking prin ciple. A free-running frequency of 311.6 GHz has been measured by down-converting the signal. Ad di tionally, injection locking has been successfully demonstrated with up to 17.8 dB of injection-locking gain. The injection-locking reference signal is generated using a 2 20 GHz frequency synthesizer, followed by a doubler, active tripler, a W-band amplifier, and then a passive tripler. Therefore, the source frequency is multiplied 18 times to obtain a signal above 300 GHz that can be used to injection lock the oscillator. Measurement shows that injection locking has improved the phase noise of the oscillator and can be also used for synchronizing a series of oscillators. A signal conductor is implemented near the BCP -InP interface and the topside of the BCB layer is fully metallized as a signal ground. Because the fields are primarily constrained in the lower permittivity BCB region, this type of transmission line is referred to as an inverted microstrip. In addition, both common-emitter and commonbase circuits were investigated to determine optimum topology for oscillator design. The common -base topology required smaller

  18. A Frequency-Reconfigurable Monopole Antenna with Switchable Stubbed Ground Structure

    Directory of Open Access Journals (Sweden)

    X. L. Liu

    2015-06-01

    Full Text Available A frequency-reconfigurable coplanar-waveguide (CPW fed monopole antenna using switchable stubbed ground structure is presented. Four PIN diodes are employed in the stubs stretching from the ground to make the antenna reconfigurable in three operating modes: a single-band mode (2.4-2.9 GHz, a dual-band mode (2.4-2.9 GHz/5.09-5.47 GHz and a triple-band mode (3.7-4.26 GHz/5.3-6.3 GHz/8.0-8.8 GHz. The monopole antenna is resonating at 2.4 GHz, while the stubs produce other operating frequency bands covering a number of wireless communication systems, including WLAN, WiMAX, C-band, and ITU. Furthermore, an optimized biasing network has been integrated into this antenna, which has little influence on the performance of the antenna. This paper presents, compares and discusses the simulated and measured results.

  19. Multi-year slant path rain fade statistics at 28.56 and 19.04 GHz for Wallops Island, Virginia

    Science.gov (United States)

    Goldhirsh, J.

    1979-01-01

    Multiyear rain fade statistics at 28.56 GHz and 19.04 GHz were compiled for the region of Wallops Island, Virginia covering the time periods, 1 April 1977 through 31 March 1978, and 1 September 1978 through 31 August 1979. The 28.56 GHz attenuations were derived by monitoring the beacon signals from the COMSTAR geosynchronous satellite, D sub 2 during the first year, and satellite, D sub 3, during the second year. Although 19.04 GHz beacons exist aboard these satellites, statistics at this frequency were predicted using the 28 GHz fade data, the measured rain rate distribution, and effective path length concepts. The prediction method used was tested against radar derived fade distributions and excellent comparisons were noted. For example, the rms deviations between the predicted and test distributions were less than or equal to 0.2dB or 4% at 19.04 GHz. The average ratio between the 28.56 GHz and 19.04 GHz fades were also derived for equal percentages of time resulting in a factor of 2.1 with a .05 standard deviation.

  20. Imaging of SNR IC443 and W44 with the Sardinia Radio Telescope at 1.5 and 7 GHz

    Science.gov (United States)

    Egron, E.; Pellizzoni, A.; Iacolina, M. N.; Loru, S.; Marongiu, M.; Righini, S.; Cardillo, M.; Giuliani, A.; Mulas, S.; Murtas, G.; Simeone, D.; Concu, R.; Melis, A.; Trois, A.; Pilia, M.; Navarrini, A.; Vacca, V.; Ricci, R.; Serra, G.; Bachetti, M.; Buttu, M.; Perrodin, D.; Buffa, F.; Deiana, G. L.; Gaudiomonte, F.; Fara, A.; Ladu, A.; Loi, F.; Marongiu, P.; Migoni, C.; Pisanu, T.; Poppi, S.; Saba, A.; Urru, E.; Valente, G.; Vargiu, G. P.

    2017-09-01

    Observations of supernova remnants (SNRs) are a powerful tool for investigating the later stages of stellar evolution, the properties of the ambient interstellar medium and the physics of particle acceleration and shocks. For a fraction of SNRs, multiwavelength coverage from radio to ultra-high energies has been provided, constraining their contributions to the production of Galactic cosmic rays. Although radio emission is the most common identifier of SNRs and a prime probe for refining models, high-resolution images at frequencies above 5 GHz are surprisingly lacking, even for bright and well-known SNRs such as IC443 and W44. In the frameworks of the Astronomical Validation and Early Science Program with the 64-m single-dish Sardinia Radio Telescope, we provided, for the first time, single-dish deep imaging at 7 GHz of the IC443 and W44 complexes coupled with spatially resolved spectra in the 1.5-7 GHz frequency range. Our images were obtained through on-the-fly mapping techniques, providing antenna beam oversampling and resulting in accurate continuum flux density measurements. The integrated flux densities associated with IC443 are S1.5 GHz = 134 ± 4 Jy and S7 GHz = 67 ± 3 Jy. For W44, we measured total flux densities of S1.5 GHz = 214 ± 6 Jy and S7 GHz = 94 ± 4 Jy. Spectral index maps provide evidence of a wide physical parameter scatter among different SNR regions: a flat spectrum is observed from the brightest SNR regions at the shock, while steeper spectral indices (up to ˜ 0.7) are observed in fainter cooling regions, disentangling in this way different populations and spectra of radio/gamma-ray-emitting electrons in these SNRs.

  1. 93-133 GHz Band InP High-Electron-Mobility Transistor Amplifier with Gain-Enhanced Topology

    Science.gov (United States)

    Sato, Masaru; Shiba, Shoichi; Matsumura, Hiroshi; Takahashi, Tsuyoshi; Nakasha, Yasuhiro; Suzuki, Toshihide; Hara, Naoki

    2013-04-01

    In this study, we developed a new type of high-frequency amplifier topology using 75-nm-gate-length InP-based high-electron-mobility transistors (InP HEMTs). To enhance the gain for a wide frequency range, a common-source common-gate hybrid amplifier topology was proposed. A transformer-based balun placed at the input of the amplifier generates differential signals, which are fed to the gate and source terminals of the transistor. The amplified signal is outputted at the drain node. The simulation results show that the hybrid topology exhibits a higher gain from 90 to 140 GHz than that of the conventional common-source or common-gate amplifier. The two-stage amplifier fabricated using the topology exhibits a small signal gain of 12 dB and a 3-dB bandwidth of 40 GHz (93-133 GHz), which is the largest bandwidth and the second highest gain reported among those of published 120-GHz-band amplifiers. In addition, the measured noise figure was 5 dB from 90 to 100 GHz.

  2. Sky survey at 8. 7 and 14. 4 GHz: the zone delta = 0/sup 0/--4/sup 0/

    Energy Technology Data Exchange (ETDEWEB)

    Amirkhanyan, V.; Gorshkov, A.; Kapustkin, A.; Konnikova, V.; Lazutkin, A.; Larionov, M.; Nikanorov, A.; Sidorenkov, V.; Ugol' kova, L.; Khromov, O.

    1981-07-01

    The Zelenchukskaya radio survey has been initiated with coverage of 0.33 sr of sky in the zone 0/sup 0/< or =delta< or =4/sup 0/. Concurrent observations at 8.7- and 14.4-GHz frequency disclose 82 and 24 sources, respectively, six of which have not hitherto been recorded.

  3. Development status of a 420–1980 GHz vector network analyzer for time-domain reflectometry and imaging applications

    NARCIS (Netherlands)

    Jellema, Willem; Barychev, Andrei; Paveliev, D.; Hesler, J. L.; Wild, Wolfgang; Withington, S.

    2007-01-01

    With recent progress in the area of electronically tunable solid-state sources it is possible to fully extend microwave measurement techniques into the THz frequency range. In this paper we present the development status of a 420-1980 GHz vector network analyzer and illustrate how phase-sensitive

  4. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications

  5. Destination directed packet switch architecture for a 30/20 GHz FDMA/TDM geostationary communication satellite network

    Science.gov (United States)

    Ivancic, William D.; Shalkhauser, Mary JO

    1991-01-01

    Emphasis is on a destination directed packet switching architecture for a 30/20 GHz frequency division multiplex access/time division multiplex (FDMA/TDM) geostationary satellite communication network. Critical subsystems and problem areas are identified and addressed. Efforts have concentrated heavily on the space segment; however, the ground segment was considered concurrently to ensure cost efficiency and realistic operational constraints.

  6. Multigigabit W-Band (75–110 GHz) Bidirectional Hybrid Fiber-Wireless Systems in Access Networks

    DEFF Research Database (Denmark)

    Pang, Xiaodan; Lebedev, Alexander; Vegas Olmos, Juan José

    2014-01-01

    We experimentally demonstrate multigigabit capacity bidirectional hybrid fiber-wireless systems with RF carrier frequencies at the W-band (75-110 GHz) that enables the seamless convergence between wireless and fiber-optic data transmission systems in access networks. In this study, we evaluate...

  7. Circuit-switch architecture for a 30/20-GHz FDMA/TDM geostationary satellite communications network

    Science.gov (United States)

    Ivancic, William D.

    1992-01-01

    A circuit switching architecture is described for a 30/20 GHz frequency division, multiple access uplink/time division multiplexed downlink (FDMA/TDM) geostationary satellite communications network. Critical subsystems and problem areas are identified and addressed. Work was concentrated primarily on the space segment; however, the ground segment was considered concurrently to ensure cost efficiency and realistic operational constraints.

  8. Destination-directed, packet-switching architecture for 30/20-GHz FDMA/TDM geostationary communications satellite network

    Science.gov (United States)

    Ivancic, William D.; Shalkhauser, Mary JO

    1992-01-01

    A destination-directed packet switching architecture for a 30/20-GHz frequency division multiple access/time division multiplexed (FDMA/TDM) geostationary satellite communications network is discussed. Critical subsystems and problem areas are identified and addressed. Efforts have concentrated heavily on the space segment; however, the ground segment has been considered concurrently to ensure cost efficiency and realistic operational constraints.

  9. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications t

  10. A Novel Geometrical Height Gain Model for Line-of-Sight Urban Micro Cells Below 6 GHz

    DEFF Research Database (Denmark)

    Rodriguez, Ignacio; Nguyen, Huan Cong; Sørensen, Troels Bundgaard;

    2016-01-01

    This paper presents a novel height gain model applicable to line-of-sight urban micro cell scenarios and frequencies below 6 GHz. The model is knife-edge diffraction-based, and it is founded on simple geometrical and physical relationships. Typical system level simulator scenario parameters...

  11. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications t

  12. Development status of a 420–1980 GHz vector network analyzer for time-domain reflectometry and imaging applications

    NARCIS (Netherlands)

    Jellema, Willem; Barychev, Andrei; Paveliev, D.; Hesler, J. L.; Wild, Wolfgang; Withington, S.

    2007-01-01

    With recent progress in the area of electronically tunable solid-state sources it is possible to fully extend microwave measurement techniques into the THz frequency range. In this paper we present the development status of a 420-1980 GHz vector network analyzer and illustrate how phase-sensitive he

  13. Fast, precise, and widely tunable frequency control of an optical parametric oscillator referenced to a frequency comb

    Science.gov (United States)

    Prehn, Alexander; Glöckner, Rosa; Rempe, Gerhard; Zeppenfeld, Martin

    2017-03-01

    Optical frequency combs (OFCs) provide a convenient reference for the frequency stabilization of continuous-wave lasers. We demonstrate a frequency control method relying on tracking over a wide range and stabilizing the beat note between the laser and the OFC. The approach combines fast frequency ramps on a millisecond timescale in the entire mode-hop free tuning range of the laser and precise stabilization to single frequencies. We apply it to a commercially available optical parametric oscillator (OPO) and demonstrate tuning over more than 60 GHz with a ramping speed up to 3 GHz/ms. Frequency ramps spanning 15 GHz are performed in less than 10 ms, with the OPO instantly relocked to the OFC after the ramp at any desired frequency. The developed control hardware and software are able to stabilize the OPO to sub-MHz precision and to perform sequences of fast frequency ramps automatically.

  14. A 4-9 GHz 10 W wideband power amplifier

    Institute of Scientific and Technical Information of China (English)

    陈中子; 陈晓娟; 姚小江; 袁婷婷; 刘新宇; 李滨

    2009-01-01

    A 4-9 GHz wideband high power amplifier is designed and fabricated, which has demonstrated saturated output power of 10 W covering 6-8 GHz band, and above 6 W over the other band. This PA module uses a bal-ance configuration, and presents power gain of 7.3 ± 0.9 dB over the whole 4-9 GHz band and 39% power-added efficiency (PAE) at 8 GHz. Both the input and output VSWR are also excellent, which are bellow -10 dB.

  15. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    Energy Technology Data Exchange (ETDEWEB)

    The Planck CTP Working Group; Ashdown, M.A.J.; Baccigalupi, C.; Bartlett, J.G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; Gorski, K.M.; Hivon, E.; Huffenberger, K.; Keihanen, E.; Keskitalo, R.; Kisner, T.; Hurki-Suonio, H.; Lawrence, C.R.; Natoli, P.; Poutanen, T.; Prezeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R..; Villa, F.; Wandelt, B.; de Troia, G.

    2008-06-19

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. They simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground component (both galactic and extra-galactic), instrument nolise (correlated and white), and the four instrument systematic effects. They made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. They also compared the maps of different mapmaking codes to see how they performed. They used five mapmaking codes (two destripers and three optimal codes). None of their mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because every map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual RMS) is baseline length. All optimal codes give essentially indistiguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  16. Making maps from Planck LFI 30 GHz data with asymmetric beams and cooler noise

    Science.gov (United States)

    Ashdown, M. A. J.; Baccigalupi, C.; Bartlett, J. G.; Borrill, J.; Cantalupo, C.; de Gasperis, G.; de Troia, G.; Górski, K. M.; Hivon, E.; Huffenberger, K.; Keihänen, E.; Keskitalo, R.; Kisner, T.; Kurki-Suonio, H.; Lawrence, C. R.; Natoli, P.; Poutanen, T.; Prézeau, G.; Reinecke, M.; Rocha, G.; Sandri, M.; Stompor, R.; Villa, F.; Wandelt, B.; Planck Ctp Working Group

    2009-01-01

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. Temperature and polarization frequency maps made from these observations are prime deliverables of the Planck mission. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. We simulated one-year long observations of four 30 GHz detectors. The simulated timestreams contained cosmic microwave background (CMB) signal, foreground components (both galactic and extra-galactic), instrument noise (correlated and white), and the four instrument systematic effects. We made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. We also compared the maps of different mapmaking codes to see how they performed. We used five mapmaking codes (two destripers and three optimal codes). None of our mapmaking codes makes any attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. This is a complicated smoothing, because each map pixel has its own effective beam. Temperature to polarization cross-coupling due to beam mismatch causes a detectable bias in the TE spectrum of the CMB map. The effects of cooler noise and pointing errors did not appear to be major concerns for the 30 GHz channel. The only essential difference found so far between mapmaking codes that affects accuracy (in terms of residual root-mean-square) is baseline length. All optimal codes give essentially indistinguishable results. A destriper gives the same result as the optimal codes when the baseline is set short enough (Madam). For longer baselines destripers (Springtide and Madam) require less computing resources but deliver a noisier map.

  17. Simple optical frequency comb generation using a passively mode-locked quantum dot laser

    Science.gov (United States)

    Liu, Li; Zhang, Xiupu; Xu, Tiefeng; Dai, Zhenxiang; Liu, Taijun

    2017-08-01

    A simple and quasi-tunable optical frequency comb (OFC) generator is proposed and experimentally demonstrated using a C-band passively Fabry-Pérot quantum dot mode-locked laser and a dual-driven LiNbO3 Mach-Zehnder modulator. A 16-nm bandwidth OFC with 81, 58 and 30 comb lines at frequency interval of 23.3 GHz, 35 GHz and 70 GHz respectively is obtained experimentally. Measured average optical signal to noise ratio of 10-dB bandwidth OFCs is 36.3 dB, 38.5 dB and 40.8 dB at frequency interval of 23.3 GHz, 35 GHz and 70 GHz, respectively. Besides, single-sideband phase noise of the 23.3 GHz and 35 GHz frequency comb is -110 dBc/Hz and -102 dBc/Hz at an offset of 1 kHz, respectively. RF linewidth of the 23.3 GHz and 35 GHz OFC is about from 275 Hz to 289 Hz. This is considered a very simple OFC generator with a broadband and seamless spectrum.

  18. Optical-network-connected multi-channel 96-GHz-band distributed radar system

    Science.gov (United States)

    Kanno, Atsushi; Kuri, Toshiaki; Kawanishi, Tetsuya

    2015-05-01

    The millimeter-wave (MMW) radar is a promising candidate for high-precision imaging because of its short wavelength and broad range of available bandwidths. In particular in the frequency range of 92-100 GHz, which is regulated for radiolocation, an atmospheric attenuation coefficient less than 1 dB/km limits the imaging range. Therefore, a combination of MMW radar and distributed antenna system directly connected to optical fiber networks can realize both high-precision imaging and large-area surveillance. In this paper, we demonstrate a multi-channel MMW frequency-modulated continuous-wave distributed radar system connected to an analog radio-over-fiber network.

  19. Wide-band residual phase-noise measurements on 40-GHz monolithic mode-locked lasers

    DEFF Research Database (Denmark)

    Larsson, David; Hvam, Jørn Märcher

    2005-01-01

    We have performed wide-band residual phase-noise measurements on semiconductor 40-GHz mode-locked lasers by employing electrical waveguide components for the radio-frequency circuit. The intrinsic timing jitters of lasers with one, two, and three quantum wells (QW) are compared and our design...... prediction, concerning noise versus number of QWs, for the first time corroborated by experiments. A minimum jitter of 44 fs is found, by extrapolating to the Nyquist frequency, for the one-QW device having nearly transform-limited pulses of 1.2 ps. This jitter is nearly three times lower than for a three...

  20. Status of the new multi-frequency ECRH system for ASDEX Upgrade

    DEFF Research Database (Denmark)

    Wagner, D.; Grünwald, G.; Leuterer, F.

    2008-01-01

    Currently, a new multi-frequency ECRH system is under construction at the ASDEX Upgrade tokamak experiment. This system employs, for the first time in a fusion device, multi-frequency gyrotrons, step-tunable in the range 105-140 GHz. The first two gyrotrons, working at 105 and 140 GHz, were...

  1. A 1.5 V 7.656 GHz PLL with I/Q outputs for a UWB synthesizer

    Energy Technology Data Exchange (ETDEWEB)

    Chen Pufeng; Zhang Haiying; Ye Tianchun, E-mail: chenpufeng@ime.ac.c [Institute of Microelectronics, Chinese Academy of Sciences, Beijing 100029 (China)

    2010-06-15

    A fully integrated CMOS phase-locked loop (PLL) which can synthesize a quadrature output frequency of 7.656 GHz is presented. The proposed PLL can be employed as a building block for an MB-OFDM UWB frequency synthesizer. To achieve fast loop settling, integer- N architecture operating with 66 MHz reference frequency and wideband QVCO are implemented. I/Q carriers are generated by two bottom-series cross-coupled LC VCOs. Realized in 0.18 {mu}m CMOS technology, this PLL consumes 16 mA current (including buffers) from a 1.5 V supply and the phase noise is -109.6 dBc/Hz at 1 MHz offset. The measured oscillation frequency shows that the QVCO has a range of 6.95 to 8.73 GHz. The core circuit occupies an area of 1 x 0.5 mm{sup 2}. (semiconductor integrated circuits)

  2. Using GHz Flash ADCs at STACEE

    Science.gov (United States)

    Zweerink, Jeffrey

    2002-04-01

    The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) detects 50-500 GeV gamma rays by sampling the Cherenkov light wavefront generated as the gamma rays interact with the atmosphere. Using steerable heliostat mirrors and stationary secondary optics at the National Solar Thermal Test Facility in New Mexico, the Cherenkov light is recorded using fast electronics with good timing. One significant improvement of the full 64 channel STACEE detector over earlier prototypes is the addition of GHz flash ADCs on each channel. We are developing analysis techniques to extract timing and other pulse information from the flash ADCs in order to 1.) discriminate against the abundant cosmic ray background, and 2.) understand how well the shower direction and energy can be reconstructed. We describe the techniques and present results from data taken during the 2001-2002 observing season.

  3. Deposited low temperature silicon GHz modulator

    CERN Document Server

    Lee, Yoon Ho Daniel; Lipson, Michal

    2013-01-01

    The majority of silicon photonics is built on silicon-on-insulator (SOI) wafers while the majority of electronics, including CPUs and memory, are built on bulk silicon wafers, limiting broader acceptance of silicon photonics. This discrepancy is a result of silicon photonics's requirement for a single-crystalline silicon (c-Si) layer and a thick undercladding for optical guiding that bulk silicon wafers to not provide. While the undercladding problem can be partially addressed by substrate removal techniques, the complexity of co-integrating photonics with state-of-the-art transistors and real estate competition between electronics and photonics remain problematic. We show here a platform for deposited GHz silicon photonics based on polycrystalline silicon with high optical quality suitable for high performance electro-optic devices. We demonstrate 3 Gbps polysilicon electro-optic modulator fabricated on a deposited polysilicon layer fully compatible with CMOS backend integration. These results open up an arr...

  4. High-Frequency Microwave Processing of Materials Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Conducts research on high-frequency microwave processing of materials using a highpower, continuous-wave (CW), 83-GHz, quasi-optical beam system for rapid,...

  5. A Novel Design of Frequency Reconfigurable Antenna for UWB Application

    Science.gov (United States)

    Yang, Xiaolin; Yu, Ziliang; Wu, Zheng; Shen, Huajiao

    2016-09-01

    In this paper, we present a novel frequency reconfigurable antenna which could be easily operate in a single notched-band (WiMAX (3.3-3.6 GHz)) UWB frequency band, another single notched-band (WLAN (5-6 GHz)) UWB frequency band and the dual band-notched UWB frequency band (the stopband covers the WiMAX (3.3-3.6 GHz) and WLAN (5-6 GHz)). The reconfigurability is achieved by changing the states of PIN diodes. The simulated results are in agreement well with the measured results. And the measured patterns are slightly changed with antenna reconfiguration. The proposed antenna is a good candidate for various UWB applications.

  6. Comparison of ultra-stable radio frequency signals synthesized from independent secondary microwave frequency standards

    CERN Document Server

    Hartnett, John G; Ivanov, Eugene N; Povey, Travis; Nand, Nitin R; Floch, Jean-Michel le

    2013-01-01

    The phase noise and frequency stability measurements of 1 GHz, 100 MHz, and 10 MHz signals are presented which have been synthesized from microwave cryogenic sapphire oscillators using ultra-low-vibration pulse-tube cryocooler technology. We present the measured data using independent cryogenic oscillators for the 100 MHz and 10 MHz synthesized signals, whereas previously we only estimated the expected results based on residual phase noise measurements, when only one cryogenic oscillator was available. In addition we present the design of a 1 GHz synthesizer using a Crystek voltage controlled oscillator phase locked to 1 GHz output derived from a cryogenic sapphire oscillator.

  7. A novel NiZn ferrite integrated magnetic solenoid inductor with a high quality factor at 0.7–6 GHz

    Directory of Open Access Journals (Sweden)

    Xinjun Wang

    2017-05-01

    Full Text Available Integrated inductor is one of the fundamental components and has been widely used in radio frequency integrated circuits (RFICs. It has been challenging to achieve simultaneously high inductance and quality factor, particularly at GHz frequencies. In this work, we reported a novel integrated solenoid inductor with a magnetic NiZn ferrite as the core material, which was deposited by a low-cost spin spray technique. These integrated inductors showed a significant improvement in both inductance and quality factor at GHz frequencies over their air core counterparts. A stable inductance was observed within a wide frequency ranged from 700 MHz to 6 GHz. The peak value of quality factor reached 23, a relatively higher value not reported for solenoid inductors up to date. Our results indicate that the integrated inductor are promising for applications in RFICs.

  8. Up to 400 GHz burst-mode pulse generation from a hybrid harmonic mode-locked Er-doped fibre laser

    Science.gov (United States)

    Wang, Sheng-Min; Lai, Yinchieh

    2017-02-01

    By inserting a birefringence filter with FSR  =  100 GHz inside a hybrid mode-locked Er-doped fibre laser, we successfully generate ps to sub-ps optical burst pulses with the intra-burst pulse rate up to 400 GHz. Multiplication of the intra-burst pulse rate is attributed to a new effect analogous to rational harmonic mode-locking, which occurs due to the relative alignment of the cavity harmonic frequencies, the external phase modulation induced frequencies, and the filter-selected frequencies.

  9. Development and characterization of nickel–zinc spinel ferrite for microwave absorption at 2.4 GHz

    Indian Academy of Sciences (India)

    A Kakirde; B Sinha; S N Sinha

    2008-10-01

    This paper deals with the development and characterization of nickel–zinc spinel ferrite (Ni(1–) ZnFe2O4) for microwave absorption at 2.4 GHz (ISM band). The ferrite powder was prepared by dry attrition and sintering process. Complex permittivity and permeability of the prepared sample have been determined by measuring its scattering parameters with the help of a vector network analyser. The measured parameters have been used to determine its wave absorption properties over a frequency range 2.1–2.6 GHz.

  10. A 29.3-GHz cavity-enclosed aperture-coupled circular-patch antenna for microwave circuit integration

    Science.gov (United States)

    Navarro, Julio A.; Chang, Kai; Tolleson, Joseph; Sanzgiri, Shashi; Lee, R. Q.

    1991-01-01

    A circular patch antenna fed by an aperture-coupled microstrip line has been demonstrated at 29.3 GHz. The patch was enclosed by a cavity to reduce surface-wave interactions in an array environment and to improve heat dissipation when using active devices. The antenna exhibited a 2:1 input VSWR (voltage standing wave ratio) over a bandwidth of 12 percent from 27.52 to 30.95 GHz. The antenna should have applications in conformal phased arrays at millimeter-wave frequencies.

  11. Single- and Multiband OFDM Photonic Wireless Links in the 75−110 GHz Band Employing Optical Combs

    DEFF Research Database (Denmark)

    Beltrán, M.; Deng, Lei; Pang, Xiaodan

    2012-01-01

    The photonic generation of electrical orthogonal frequency-division multiplexing (OFDM) modulated wireless signals in the 75−110 GHz band is experimentally demonstrated employing in-phase/quadrature electrooptical modulation and optical heterodyn upconversion. The wireless transmission of 16......-quadrature-amplitude-modulation OFDM signals is demonstrated with a bit error rate performance within the forward error correction limits. Signals of 19.1 Gb/s in 6.3-GHz bandwidth are transmitted over up to 1.3-m wireless distance. Optical comb generation is further employed to support different channels...

  12. 7~11GHz CMOS环形压控振荡器的设计%Design of a 7-11 GHz Ring VCO Based on CMOS Process

    Institute of Scientific and Technical Information of China (English)

    何芝兰; 段吉海

    2011-01-01

    设计了一种全集成差分高速环形压控振荡器(VCO).采用三级延迟单元环路复用结构,通过正反馈技术以及改变负载电阻值的方法,有效优化延迟单元;采用双控制电压粗/细调谐方式,实现振荡器高频率、低功耗的要求.在SMIC 0.18μm CMOS RF工艺模型下,采用ADS软件对振荡电路进行仿真,在外接电源电压Vdd=1.8 V时,输出频率的调谐范围为7.32~11.07 GHz,当频率为11 GHz时,在偏离中心频率1 MHz处相位噪声为-88.32 dBc/Hz,在偏离中心频率10MHz处相位噪声为-112.7 dBc/Hz,平均功耗为63.5 mW.该VCO可应用于锁相环和雷达通信系统.%A fully integrated differential high-speed ring voltage-controlled oscillator (VCO) was designed, which was comprised of three-stage delay cell with multi-loop structure. The delay cell was optimized by using positive feedback and modifying load resistance value. In this circuit, high frequency and low power was realized by coarse/ fine frequency control. Based on SMIC's 0.18 um 1P6M CMOS process model, the VCO was simulated with ADS. At 1. 8 V supply voltage, the VCO had a linear tuning range from 7. 32 GHz to 11. 07 GHz. Simulation results showed that, for an oscillating frequency of 11 GHz, the circuit had a phase noise of -88. 32 dBc/Hz and -112. 7 dBc/Hz at 1 MHz and 10 MHz off center frequency, respectively, with an average power of 63. 5 mW.

  13. Customer premise service study for 30/20 GHz satellite system

    Science.gov (United States)

    Milton, R. T.; Ross, D. P.; Harcar, A. R.; Freedenberg, P.; Schoen, D.

    1983-01-01

    Satellite systems in which the space segment operates in the 30/20 GHz frequency band are defined and compared as to their potential for providing various types of communications services to customer premises and the economic and technical feasibility of doing so. Technical tasks performed include: market postulation, definition of the ground segment, definition of the space segment, definition of the integrated satellite system, service costs for satellite systems, sensitivity analysis, and critical technology. Based on an analysis of market data, a sufficiently large market for services is projected so as to make the system economically viable. A large market, and hence a high capacity satellite system, is found to be necessary to minimize service costs, i.e., economy of scale is found to hold. The wide bandwidth expected to be available in the 30/20 GHz band, along with frequency reuse which further increases the effective system bandwidth, makes possible the high capacity system. Extensive ground networking is required in most systems to both connect users into the system and to interconnect Earth stations to provide spatial diversity. Earth station spatial diversity is found to be a cost effective means of compensating the large fading encountered in the 30/20 GHz operating band.

  14. A Low Phase Noise Fully Monolithic 6 GHz Differential Coupled NMOS LC-VCO

    Science.gov (United States)

    Moalla, Dorra Mellouli; Cordeau, David; Mnif, Hassene; Paillot, Jean-Marie; Loulou, Mourad

    2016-01-01

    A fully monolithic 6 GHz low-phase noise Voltage-Controlled-Oscillator (VCO) is presented in this paper. It consists in two LC-NMOS differential VCOs coupled through a resistive network and is implemented on a 0.25 µm BiCMOS SiGe process. This proposed integrated VCO can be used also for phased-array applications to steer the beam over the entire spatial range. In this case, the radiation pattern of the phased antenna array is steered in a particular direction by establishing a constant phase progression in the oscillator chain which can be obtained by detuning the free-running frequencies of the two oscillators in the array. At 2.5 V power supply voltage and a power dissipation of 62.5 mW, the coupled VCO array features a measured worst case phase noise of -102.4 dBc/Hz and -125.64 dBc/Hz at 100 kHz and 1 MHz frequency offset respectively from a 6 GHz carrier. The tuning range is about 400 MHz, from 5.85 to 6.25 GHz, for a tuning voltage varying from 0 to 2.5 V.

  15. THz photonic wireless links with 16-QAM modulation in the 375-450 GHz band.

    Science.gov (United States)

    Jia, Shi; Yu, Xianbin; Hu, Hao; Yu, Jinlong; Guan, Pengyu; Da Ros, Francesco; Galili, Michael; Morioka, Toshio; Oxenløwe, Leif K

    2016-10-17

    We propose and experimentally demonstrate THz photonic wireless communication systems with 16-QAM modulation in the 375-450 GHz band. The overall throughput reaches as high as 80 Gbit/s by exploiting four THz channels with 5 Gbaud 16-QAM baseband modulation per channel. We create a coherent optical frequency comb (OFC) for photonic generation of multiple THz carriers based on photo-mixing in a uni-travelling carrier photodiode (UTC-PD). The OFC configuration also allows us to generate reconfigurable THz carriers with low phase noise. The multiple-channel THz radiation is received by using a Schottky mixer based electrical receiver after 0.5 m free-space wireless propagation. 2-channel (40 Gbit/s) and 4-channel (80 Gbit/s) THz photonic wireless links with 16-QAM modulation are reported in this paper, and the bit error rate (BER) performance for all channels in both cases is below the hard decision forward error correction (HD-FEC) threshold of 3.8e-3 with 7% overhead. In addition, we also successfully demonstrate hybrid photonic wireless transmission of 40 Gbit/s 16-QAM signal at carrier frequencies of 400 GHz and 425 GHz over 30 km standard single mode fiber (SSMF) between the optical baseband signal transmitter and the THz wireless transmitter with negligible induced power penalty.

  16. Comparison of OQPSK and CPM for Communications at 60 GHz with a Nonideal Front End

    Directory of Open Access Journals (Sweden)

    Jimmy Nsenga

    2007-03-01

    Full Text Available Short-range digital communications at 60 GHz have recently received a lot of interest because of the huge bandwidth available at those frequencies. The capacity offered to the users could finally reach 2 Gbps, enabling the deployment of new multimedia applications. However, the design of analog components is critical, leading to a possible high nonideality of the front end (FE. The goal of this paper is to compare the suitability of two different air interfaces characterized by a low peak-to-average power ratio (PAPR to support communications at 60 GHz. On one hand, we study the offset-QPSK (OQPSK modulation combined with a channel frequency-domain equalization (FDE. On the other hand, we study the class of continuous phase modulations (CPM combined with a channel time-domain equalizer (TDE. We evaluate their performance in terms of bit error rate (BER considering a typical indoor propagation environment at 60 GHz. For both air interfaces, we analyze the degradation caused by the phase noise (PN coming from the local oscillators; and by the clipping and quantization errors caused by the analog-to-digital converter (ADC; and finally by the nonlinearity in the PA.

  17. Comparison of OQPSK and CPM for Communications at 60 GHz with a Nonideal Front End

    Directory of Open Access Journals (Sweden)

    Nsenga Jimmy

    2007-01-01

    Full Text Available Short-range digital communications at 60 GHz have recently received a lot of interest because of the huge bandwidth available at those frequencies. The capacity offered to the users could finally reach 2 Gbps, enabling the deployment of new multimedia applications. However, the design of analog components is critical, leading to a possible high nonideality of the front end (FE. The goal of this paper is to compare the suitability of two different air interfaces characterized by a low peak-to-average power ratio (PAPR to support communications at 60 GHz. On one hand, we study the offset-QPSK (OQPSK modulation combined with a channel frequency-domain equalization (FDE. On the other hand, we study the class of continuous phase modulations (CPM combined with a channel time-domain equalizer (TDE. We evaluate their performance in terms of bit error rate (BER considering a typical indoor propagation environment at 60 GHz. For both air interfaces, we analyze the degradation caused by the phase noise (PN coming from the local oscillators; and by the clipping and quantization errors caused by the analog-to-digital converter (ADC; and finally by the nonlinearity in the PA.

  18. Atmospheric-pressure microgap plasma produced by 10-GHz microwave excitation

    Science.gov (United States)

    Kono, A.; Kobayashi, M.; Aramaki, M.

    2007-10-01

    Atmospheric pressure high-density glow discharge can be sustained continuously in the microgap (100-μm wide) between two knife-edge electrodes by microwave excitation. Detailed characterizations of a microgap plasma produced by 2.45-GHz microwave excitation were reported previously, including electron density and temperature measurements using laser Thomson scattering, gas temperature measurements under the influence of gas flow, etc. In the present study, we investigate the effect of microwave frequency on the electron density, in view of the analogy with the fact of increasing electron heating efficiency with increasing driving frequency in usual rf low-pressure capacitively coupled discharge. Preliminary studies on three different electrode configurations and microwave driving schemes indicate that the electron density do not reach that in the case of 2.45-GHz excitation, suggesting a large radiation loss of the microwave power in 10-GHz excitation. A discharge structure to reduce the radiation loss is being pursued. (Work supported by Grant-in-aid 15075205 from MEXT Japan.)

  19. Propagation Channel Comparison between 23.5 and 45 GHz in Conference Scenario

    Directory of Open Access Journals (Sweden)

    Jianwu Dou

    2016-01-01

    Full Text Available The characteristics of propagation channel at 23.5 and 45 GHz in an indoor conference room are studied based on hybrid approach. A ray-based simulator which includes the reflection, penetration, diffraction, and diffuse scattering is adopted to generate the massive channel realizations. This platform is well calibrated in path and power delay profile (PDP levels according to some specified measurements at different frequencies. Subsequently, according to the simulated channel samples, the statistical channel model for both the large and small scale characteristics is established based on the alpha-beta approach and extended Saleh-Valenzuela (S-V structure, respectively. Results show that the slope of fitted path loss (PL is less than free space due to the waveguide effect for both 23.5 and 45 GHz in indoor scenario and larger PL is experienced at higher frequency. Additionally, the cluster is more centralized with less spreads and decaying faster in delay domain at 45 GHz.

  20. Microwave Dielectric Properties of Alfalfa Leaves From 0.3 to 18 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Sokhansanj, Shahabaddine [ORNL; Shrestha, Bijay [University of Saskatchewan; Wood, H.C. [University of Saskatchewan

    2011-01-01

    Dielectric properties (i.e., permittivity) are essential in designing, simulating, and modeling microwave applications. The permittivity of stacked leaves of alfalfa (Medicago sativa) were measured with a network analyzer and a coaxial probe, and the effect of moisture content (MC: 12% 73% wet basis), frequency (300 MHz to 18 GHz), bound water (Cole Cole dispersion equation), temperature ( 15 C and 30 C), leaf-orientation, and pressure (0 11 kPa) were investigated. The measured permittivity increased with MC. A critical moisture level (CML) of 23% was reported, below which the permittivity decreased with increasing frequency at 22 C. Above CML and up to 5 GHz, the dielectric constants followed the Cole Cole dispersion, and the dielectric loss factors consisted of ionic and bound water losses. Above 5 GHz, the behavior of the dielectric constant was similar to that of free water, and the polar losses became dominant. Above 0 C, the measured permittivity followed a trend similar to that of free saline water and was characterized by the Debye equation. Below 0 C, it was dominated by nonfreezing bound and unfrozen supercooled moistures. The relaxation parameters and the optimum pressure (9 kPa) for the leaf measurements were determined. The effects of variations among the samples, and their orientations had negligible effects on the measured permittivity.

  1. Making Maps from Planck LFI 30GHz Data with Asymmetric Beams and Cooler Noise

    CERN Document Server

    Ashdown, M A J; Bartlett, J G; Borrill, J; Cantalupo, C; De Gasperis, G; de Troia, G; Górski, K M; Hivon, E; Huffenberger, Kevin M; Keihanen, E; Keskitalo, R; Kisner, T; Kurki-Suonio, H; Lawrence, C R; Natoli, P; Poutanen, T; Prezeau, G; Reinecke, M; Rocha, G; Sandri, M; Stompor, R; Villa, F; Wandelt, B

    2008-01-01

    The Planck satellite will observe the full sky at nine frequencies from 30 to 857 GHz. The goal of this paper is to examine the effects of four realistic instrument systematics in the 30 GHz frequency maps: non-axially-symmetric beams, sample integration, sorption cooler noise, and pointing errors. We simulated one year long observations of four 30 GHz detectors. The simulated timestreams contained CMB, foreground components (both galactic and extra-galactic), instrument noise (correlated and white), and the four instrument systematic effects. We made maps from the timelines and examined the magnitudes of the systematics effects in the maps and their angular power spectra. We also compared the maps of different mapmaking codes to see how they performed. We used five mapmaking codes (two destripers and three optimal codes). None of our mapmaking codes makes an attempt to deconvolve the beam from its output map. Therefore all our maps had similar smoothing due to beams and sample integration. Temperature to pol...

  2. The 700-950 GHz Superconducting Receiving Structures for Radio Astronomy

    Science.gov (United States)

    Rudakov, K. I.; Koshelets, V. P.; Baryshev, A. M.; Dmitriev, P. N.; Khudchenko, A. V.

    2017-01-01

    We have designed, fabricated, and tested the waveguide receiving element, which is based on the tunnel superconductor-insulator-superconductor structures, for the frequency range 790-950 GHz. Two Nb/AlN/NbN tunnel junctions are incorporated in a microstrip line consisting of the bottom NbTiN-film electrode with a thickness of about 300 nm and the top 500 nm-thick aluminum electrode. The production-process optimization allows one to ensure the following characteristics of these junctions: submicron area (0.5 μm2 for each junction), current density about 30 kA/cm2, and band gap width 3.2 mV. Such tunnel junctions ensure the receiver operation in a wide frequency range (700-950 GHz), which was confirmed by the Fourier transform spectroscopy and the noise-temperature measurements. At a frequency of 725 Hz, the corrected noise temperature of the receiver amounts to 120 K, which is only threefold greater than the quantum limit hf/kB, where h is the Planck's constant, f is the frequency, and kB is Boltzmann's constant. In the upper part of this frequency range, the noise temperature increases up to 390 K.

  3. Broadband antenna with frequency scanning

    Directory of Open Access Journals (Sweden)

    A. A. Shekaturin

    2014-06-01

    Full Text Available Relevance of this study. The main advantage of frequency scanning is simplicity of implementation. At this point, multifunctional usage of microwave modules is an urgent task, as well as their maximum simpler and cheaper. Antenna design and operation. The study is aimed at providing electric antenna with frequency scanning. It was based on the log-periodic antenna due to its wideband and negotiation capability over the entire operating frequency range. For this distribution line is bent in an arc of a circle in a plane blade while vibrators are arranged along the radius. Computer modeling of antennas with frequency scanning. Modeled with a non-mechanical motion antenna beam emitters representing system for receiving a radio frequency signal on mobile objects calculated for 1.8 GHz ... 4.2 GHz. The simulation was performed in a software environment for numerical modeling of electromagnetic «Feko 5.5». Analysis of the interaction of radiation is based on the method of moments. Findings. The result of this work is to propose a new design of the antenna with a frequency scanning method as agreed in a wide frequency range. In the studied technical solution provided by the rotation of NAM in the frequency range, and the matching of the antenna to the feed line is maintained. Application of this type of antennas on the proposed technical solution in communication systems will improve the communication reliability by maintaining coordination in the frequency range

  4. Design of 340 GHz 2× and 4× Sub-Harmonic Mixers Using Schottky Barrier Diodes in Silicon-Based Technology

    Directory of Open Access Journals (Sweden)

    Chao Liu

    2015-05-01

    Full Text Available This paper presents the design of terahertz 2× and 4× sub-harmonic down-mixers using Schottky Barrier Diodes fabricated in standard 0.13 μm SiGe BiCMOS technology. The 340 GHz sub-harmonic mixers (SHMs are designed based on anti-parallel-diode-pairs (APDPs. With the 2nd and 4th harmonic, local oscillator (LO frequencies of 170 GHz and 85 GHz are used to pump the two 340 GHz SHMs. With LO power of 7 dBm, the 2× SHM exhibits a conversion loss of 34.5–37 dB in the lower band (320–340 GHz and 35.5–41 dB in the upper band (340–360 GHz; with LO power of 9 dBm, the 4× SHM exhibits a conversion loss of 39–43 dB in the lower band (320–340 GHz and 40–48 dB in the upper band (340–360 GHz. The measured input 1-dB conversion gain compression point for the 2× and 4× SHMs are −8 dBm and −10 dBm at 325 GHz, respectively. The simulated LO-IF (intermediate frequency isolation of the 2× SHM is 21.5 dB, and the measured LO-IF isolation of the 4× SHM is 32 dB. The chip areas of the 2× and 4× SHMs are 330 μm × 580 μm and 550 μm × 610 μm, respectively, including the testing pads.

  5. Tunable Narrow Linewidth, Low Noise 2.05 Micron Single Frequency Seeder Laser Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an all-fiber based 2.05-micron single frequency, narrow linewidth seeder laser with 10 nm tuning range and 5GHz frequency modulation for next generation...

  6. Tunable Narrow Linewidth, Low Noise 2.05 Micron Single Frequency Seeder Laser Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an all-fiber based 2.05-micron single frequency, narrow linewidth seeder laser with 10 nm tuning range and 5GHz frequency modulation for next generation...

  7. Detection of 183 GHz water megamaser emission towards NGC 4945

    CERN Document Server

    Humphreys, Elizabeth; Impellizzeri, Violette; Galametz, Maud; Olberg, Michael; Conway, John; Belitsky, Victor; De Breuck, Carlos

    2016-01-01

    Aim: The aim of this work is to search Seyfert 2 galaxy NGC 4945, a well-known 22 GHz water megamaser galaxy, for water (mega)maser emission at 183 GHz. Method: We used APEX SEPIA Band 5 to perform the observations. Results: We detected 183 GHz water maser emission towards NGC 4945 with a peak flux density of ~3 Jy near the galactic systemic velocity. The emission spans a velocity range of several hundred km/s. We estimate an isotropic luminosity of > 1000 Lsun, classifying the emission as a megamaser. A comparison of the 183 GHz spectrum with that observed at 22 GHz suggests that 183 GHz emission also arises from the active galactic nucleus (AGN) central engine. If the 183 GHz emission originates from the circumnuclear disk, then we estimate that a redshifted feature at 1084 km/s in the spectrum should arise from a distance of 0.022 pc from the supermassive black hole (1.6 x 10(5) Schwarzschild radii), i.e. closer than the water maser emission previously detected at 22 GHz. This is only the second time 183 G...

  8. 60 Gbit/s 400 GHz Wireless Transmission

    DEFF Research Database (Denmark)

    Yu, Xianbin; Asif, Rameez; Piels, Molly;

    2015-01-01

    We experimentally demonstrate a 400 GHz carrier wireless transmission system with real-time capable detection and demonstrate transmission of a 60 Gbit/s signal derived from optical Nyquist channels in a 12.5 GHz ultra-dense wavelength division multiplexing (UD-WDM) grid and carrying QPSK modulat...

  9. The 1.4 GHZ light curve of GRB 970508

    NARCIS (Netherlands)

    Galama, TJ; Wijers, RAMJ; Groot, PJ; Strom, RG; De Bruyn, AG; Kouveliotou, C; Robinson, CR; van Paradus, J

    1998-01-01

    We report on Westerbork 1.4 GHz radio observations of the radio counterpart to gamma-ray burst GRB 970508, between 0.80 and 138 days after this event. The 1.4 GHz light curve shows a transition from optically thick to thin emission between 39 and 54 days after the event. We derive the slope p of the

  10. 79 GHz UWB automotive short range radar - Spectrum allocation and technology trends

    Science.gov (United States)

    Bloecher, H.-L.; Sailer, A.; Rollmann, G.; Dickmann, J.

    2009-05-01

    Automotive UWB (Ultra-Wideband) short range radar (SSR) is on the market as a key technology for novel comfort and safety systems. SiGe based 79 GHz UWB SRR will be a definite candidate for the long term substitution of the 24 GHz UWB SRR. This paper will give an overview of the finished BMBF joint project KOKON and the recently started successing project RoCC, which concentrate on the development of this technology and sensor demonstrators. In both projects, the responsibilities of Daimler AG deal with application based sensor specification, test and evaluation of realized sensor demonstrators. Recent UWB SRR frequency regulation approaches and activitites will be introduced. Furthermore, some first results of Daimler activities within RoCC will be presented, dealing with the packaging and operation of these sensors within the complex car environment.

  11. 79 GHz UWB automotive short range radar – Spectrum allocation and technology trends

    Directory of Open Access Journals (Sweden)

    H.-L. Bloecher

    2009-05-01

    Full Text Available Automotive UWB (Ultra-Wideband short range radar (SSR is on the market as a key technology for novel comfort and safety systems. SiGe based 79 GHz UWB SRR will be a definite candidate for the long term substitution of the 24 GHz UWB SRR. This paper will give an overview of the finished BMBF joint project KOKON and the recently started successing project RoCC, which concentrate on the development of this technology and sensor demonstrators. In both projects, the responsibilities of Daimler AG deal with application based sensor specification, test and evaluation of realized sensor demonstrators. Recent UWB SRR frequency regulation approaches and activitites will be introduced. Furthermore, some first results of Daimler activities within RoCC will be presented, dealing with the packaging and operation of these sensors within the complex car environment.

  12. Micromachined On-Chip Dielectric Resonator Antenna Operating at 60 GHz

    KAUST Repository

    Sallam, Mai

    2015-06-01

    This paper presents a novel cylindrical Dielectric Resonator Antenna (DRA) suitable for millimeter-wave on-chip systems. The antenna was fabricated from a single high resistivity silicon wafer via micromachining technology. The new antenna was characterized using HFSS and experimentally with good agreement been found between the simulations and experiment. The proposed DRA has good radiation characteristics, where its gain and radiation efficiency are 7 dBi and 79.35%, respectively. These properties are reasonably constant over the working frequency bandwidth of the antenna. The return loss bandwidth was 2.23 GHz, which corresponds to 3.78% around 60 GHz. The antenna was primarily a broadside radiator with -15 dB cross polarization level.

  13. Performance Analysis of a 60 GHz Near Gigabit System for WPAN Applications

    CERN Document Server

    Rakotondrainibe, Lahatra; Zaharia, Gheorghe; Grunfelder, Guy; Zein, Ghaïs El

    2010-01-01

    A 60 GHz wireless Gigabit Ethernet (G.E.) communication system capable of near gigabit data rate has been developed at IETR. The realized system covers 2 GHz available bandwidth. This paper describes the design and realization of the overall system including the baseband (BB), intermediate frequency (IF) and radiofrequency (RF) blocks. A differential binary shift keying (DBPSK) modulation and a differential demodulation are adopted at IF. In the BB processing block, an original byte/frame synchronization technique is designed to provide a small value of the preamble false alarm and missing probabilities. For the system performances, two different real scenarios are investigated: measurements carried out in a large gym and in hallways. Bit error rate (BER) measurements have been performed in different configurations: with/without RS (255, 239) coding, with frame synchronization using 32/64 bits preambles. As shown by simulation, the 64 bits preamble provides sufficient robustness and improves the system perfor...

  14. 1-GHz CMOS VCO design for wireless application using MEMS technology

    Science.gov (United States)

    Mohamed, Amal; Elsimary, Hamed; Ismail, Mohammed

    2000-04-01

    In this work, the design of RF VCO circuit, in which the oscillation frequency is controlled by a tunable capacitor based on microelectromechanical system (MEMS) technology is presented. The design of high Q-MEMS tunable capacitor has been accomplished through bulk micro machining with all metal micro structure. A standard CMOS process is used to carry out the fabrication of the VCO circuit with the MEMS tunable capacitor on the same chip. The main features of this design, is the enabling of a complete monolithic fabrication RF VCOs using on-chip IC compatible high-Q MEMS tunable capacitor. The performance of the MEMS capacitor is modeled with emphasis on the tunability range with the tuning voltage. The simulation results are presented to show the performance of RF VCO circuit with the MEMS tunable capacitor, which has a high-Q of about 60 at 1 GHZ and low insertion loss of -1dB at 40 GHz.

  15. Design of a Low Voltage CMOS LNA at 2 GHz with Substrate-Bias

    Science.gov (United States)

    Wan Muhamad Hatta, S. F.; Soin, N.

    2008-11-01

    A low-voltage (1.5V), 2 GHz cascode CMOS low noise amplifier (LNA) has been designed and simulated using Silvaco's SMARTSPICE RF. The proposed design employs substrate bias of 0.5V and utilizes inductive source degeneration. This paper further presents an analysis on the effect of substrate bias on the MOSFET's threshold voltage as well as the transconductance. The simulated power gain (S21) is of 5.2 dB and a noise figure (NF) of 2.2975 dB is achieved at the operating frequency of 2 GHz. The Input Referred 1dB Compression Point (P1dB) and the third-order intercept point (IP3) are -12.891 dB and -1.6844 dB respectively.

  16. Mapping Analysis of Solar Radio Burst at 17 GHz on 1992 October 27

    Institute of Scientific and Technical Information of China (English)

    YU Xing-Feng; YAO Jin-Xing

    2000-01-01

    The contour maps at 17 GHz on the 1992 October 27 solar burst are analysed. Using a nonthermal inhomogeneous model of the radio source, the variations of calculated source size with time are basically consistent with the observation of maps. The variations of calculated brightness temperature with a distance ρ displaced from the project center are in better agreement with the observation of map at 0 1: 45: 29: 889 UT. The calculation shows that the characterizing magnetic field gradient αB at the peak of 17 GHz is about 2, magnetic strength B is about 737G with the magnetic field Bm of the core being 2000 G. However in order to measure the coronal magnetic field accurately, it is necessary to obtain radio-imaging data at more frequencies.

  17. Design and Fabrication of 35 GHz GaAs Gunn Diodes .

    Directory of Open Access Journals (Sweden)

    Ishwar Chandra

    1995-01-01

    Full Text Available The paper describes design and fabrication of GaAs 100 mW Gunn diodes for operation at ~35 GHz. As the devices have low efficiency, a large ammount of input power is dessipated as heat, resulting in temperature rise in the device during operation beyond tolerable limits. Heat from these devices can be removed quickly and efficiently by using gold as integral heat sink (IHS. Further, the temperature of the device can be controlled by monitoring device area. Calculations for heat flow and expected efficiency have been done. Required Gunn structure has been grown by molecular beam epitaxy technique. The devices have been fabricated by IHS-IBR integral bonding ribbon technique. From the devices developed, 100 mW of output has been achieved in the frequency range 33-38 GHz with an efficiency of 3-4 percent.

  18. A Method to Adjust Dielectric Property of SiC Powder in the GHz Range

    Institute of Scientific and Technical Information of China (English)

    Xiaolei Su; Jie Xu; Zhimin Li; Junbo Wang; Xinhai He; Chong Fu; Wancheng Zhou

    2011-01-01

    The SiC powders by Al or N doping have been synthesized by combustion synthesis, using Al powder and NH4Cl powder as the dopants and polytetrafluoroethylene as the chemical activator. Characterization by X-ray diffraction, Raman spectrometer, scanning electron microscopy and energy dispersive spectrometer demonstrates the formation of Al doped SiC, N doped SiC and the Al and N co-doped SiC solid solution powders, respectively. The electric permittivities of prepared powders have been determined in the frequency range of 8.2-12.4 GHz. It indicates that the electric permittivities of the prepared SiC powders have been improved by the pure Al or N doping and decrease by the Al and N co-doping. The paper presents a method to adjust dielectric property of SiC powders in the GHz range.

  19. A 23 GHz high-temperature superconducting microstrip filter for radio astronomy

    Institute of Scientific and Technical Information of China (English)

    GAO Lu; GUO Jin; WANG YueHui; YU Tao; ZHANG Qiang; LI ChunGuang; ZHANG XueQiang; LI Hong; LI JunJie; LI WuXia; GU ChangZhi; MENG JiBao; FENG Ji; HE YuSheng

    2009-01-01

    This paper reports a 6-pole high-temperature superconducting (HTS) microstrip bandpass filter for radio astronomy applications. The filter has a center frequency of 23 GHz and a bandwidth the 2 GHz. We have made many efforts, such as adopting 0.25-mm-thick substrate, carefully designing the housing box and filter layout, to solve the problems in realizing a K-band planar filter. A special straight-line half-wavelength resonator (center-widen resonator) was also designed to reduce the insertion loss of the filter. The measured results showed a midband insertion loss of 0.11 dB with a ripple of 0.4 dB, and a return loss better than 11.5 dB. Good agreement was obtained between simulated and measured re-suits.

  20. Bit error rate analysis of Wi-Fi and bluetooth under the interference of 2.45 GHz RFID

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    IEEE 802.11b WLAN (Wi-Fi) and IEEE 802.15.1 WPAN (bluetooth) are prevalent nowadays, and radio frequency identification (RFID) is an emerging technology which has wider applications. 802.11b occupies unlicensed industrial, scientific and medical (ISM) band (2.4-2.483 5 GHz) and uses direct sequence spread spectrum (DSSS) to alleviate the narrow band interference and fading. Bluetooth is also one user of ISM band and adopts frequency hopping spread spectrum (FHSS) to avoid the mutual interference. RFID can operate on multiple frequency bands, such as 135 KHz, 13.56 MHz and 2.45 GHz. When 2.45 GHz RFID device, which uses FHSS, collocates with 802.11b or bluetooth, the mutual interference is inevitable. Although DSSS and FHSS are applied to mitigate the interference, their performance degradation may be very significant. Therefore, in this article, the impact of 2.45 GHz RFID on 802.11b and bluetooth is investigated. Bit error rate (BER) of 802.11b and bluetooth are analyzed by establishing a mathematical model, and the simula-tion results are compared with the theoretical analysis to justify this mathematical model.

  1. The Astrophysics of Star Formation Across Cosmic Time at $\\gtrsim$10 GHz with the Square Kilometer Array

    CERN Document Server

    Murphy, Eric J; Beswick, Rob J; Dickinson, Clive; Heywood, Ian; Hunt, Leslie K; Hyunh, Minh T; Jarvis, Matt; Karim, Alexander; Krause, Marita; Prandoni, Isabella; Seymour, Nicholas; Schinnerer, Eva; Tabatabei, Fatemeh S; Wagg, Jeff

    2014-01-01

    In this chapter, we highlight a number of science investigations that are enabled by the inclusion of Band~5 ($4.6-13.8$ GHz) for SKA1-MID science operations, while focusing on the astrophysics of star formation over cosmic time. For studying the detailed astrophysics of star formation at high-redshift, surveys at frequencies $\\gtrsim$10 GHz have the distinct advantage over traditional $\\sim$1.4 GHz surveys as they are able to yield higher angular resolution imaging while probing higher rest frame frequencies of galaxies with increasing redshift, where emission of star-forming galaxies becomes dominated by thermal (free-free) radiation. In doing so, surveys carried out at $\\gtrsim$10 GHz provide a robust, dust-unbiased measurement of the massive star formation rate by being highly sensitive to the number of ionizing photons that are produced. To access this powerful star formation rate diagnostic requires that Band~5 be available for SKA1-MID. We additionally present a detailed science case for frequency cove...

  2. Genotoxic Potential of 1.6 GHz Wireless Communication Signal: In vivo Two-Year Bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Vijayalaxmi, Vijay (University of Texas at San Antonio); Sasser, Lyle B.(SELF-EMPLOYED CONSULTANTS); Morris, J E.(GENERAL ELECTRIC CO.); Wilson, Bary W.(BATTELLE (PACIFIC NW LAB)); Anderson, Larry E.(SELF-EMPLOYED CONSULTANTS)

    2003-04-01

    Timed-pregnant Fischer 344 rats (from nineteenth day of gestation) and their nursing offspring (until weaning) were exposed to a far-field 1.6 GHz Iridium wireless communication signal for 2 h/day, 5 days/week. Far-field whole-body exposures were conducted with a field intensity of 0.43 mW/cm 2 and whole-body average specific absorption rate (SAR) of 0.036 to 0.077 W/kg (0.10 to 0.22 W/kg in the brain). This was followed by chronic, head-only exposures of male and female offspring to a near-field 1.6 GHz signal for 2 h/day, 5 days/week, over 2 years. Near-field exposures were conducted at an SAR of 0.16 or 1.6 W/kg in the brain. Concurrent sham-exposed and cage control rats were also included in the study. At the end of 2 years, all rats were necropsied. Bone marrow smears were examined for the extent of genotoxicity, assessed from the presence of micronuclei in polychromatic erythrocytes. The results indicated that the incidence of micronuclei/ 2000 polychromatic erythrocytes were not significantly different between 1.6 GHz-exposed, sham-exposed and cage control rats. The group mean frequencies were 5.6 6 1.8 (130 rats exposed to 1.6 GHz at 0.16 W/kg SAR), 5.4 6 1.5 (135 rats exposed to 1.6 GHz at 1.6 W/kg SAR), 5.6 6 1.7 (119 sham-exposed rats), and 5.8 6 1.8 (100 cage control rats). In contrast, positive control rats treated with mitomycin C exhibited significantly elevated incidence of micronuclei/2000 polychromatic erythrocytes in bone marrow cells; the mean frequency was 38.2 6 7.0 (five rats). Thus there was no evidence for excess genotoxicity in rats that were chronically exposed to 1.6 GHz compared to sham-exposed and cage controls.

  3. Dual-frequency Brillouin fiber laser for optical generation of tunable low-noise radio frequency/microwave frequency.

    Science.gov (United States)

    Geng, Jihong; Staines, Sean; Jiang, Shibin

    2008-01-01

    We demonstrate a new approach, i.e., a cw dual-frequency Brillouin fiber laser pumped by two independent single-frequency Er-doped fiber lasers, for the generation of tunable low-noise rf/microwave optical signals. Its inherent features of both linewidth narrowing effect in a Brillouin fiber cavity and common mode noise cancellation between two laser modes sharing a common cavity allow us to achieve high frequency stability without using a supercavity. Beat frequency of the dual-frequency Brillouin fiber laser can be tuned from tens of megahertz up to 100 GHz by thermally tuning the wavelengths of the two pump lasers with tuning sensitivity of approximately 1.4 GHz/ degrees C. Allan variance measurements show the beat signals have the hertz-level frequency stability.

  4. On-chip filter bank spectroscopy at 600-700 GHz using NbTiN superconducting resonators

    CERN Document Server

    Endo, A; Yates, S J C; Baselmans, J J A; Thoen, D J; Javadzadeh, S M H; van der Werf, P P; Baryshev, A M; Klapwijk, T M

    2013-01-01

    We experimentally demonstrate the principle of an on-chip submillimeter wave filter bank spectrometer, using superconducting microresonators as narrow band-separation filters. The filters are made of NbTiN/SiNx/NbTiN microstrip line resonators, which have a resonance frequency in the range of 614-685 GHz---two orders of magnitude higher in frequency than what is currently studied for use in circuit quantum electrodynamics and photodetectors. The frequency resolution of the filters decreases from 350 to 140 with increasing frequency, most likely limited by dissipation of the resonators.

  5. Beat note stabilization of a 10-60 GHz dual-polarization microlaser through optical down conversion.

    Science.gov (United States)

    Rolland, A; Brunel, M; Loas, G; Frein, L; Vallet, M; Alouini, M

    2011-02-28

    Down-conversion of a high-frequency beat note to an intermediate frequency is realized by a Mach-Zehnder intensity modulator. Optically-carried microwave signals in the 10-60 GHz range are synthesized by using a two-frequency solid-state microchip laser as a voltage-controlled oscillator inside a digital phase-locked loop. We report an in-loop relative frequency stability better than 2.5×10⁻¹¹. The principle is applicable to beat notes in the millimeter-wave range.

  6. The 30 GHz communications satellite low noise receiver

    Science.gov (United States)

    Steffek, L. J.; Smith, D. W.

    1983-10-01

    A Ka-band low noise front end in proof of concept (POC) model form for ultimate spaceborne communications receiver deployment was developed. The low noise receiver consists of a 27.5 to 30.0 GHz image enhanced mixer integrated with a 3.7 to 6.2 GHz FET low noise IF amplifier and driven by a self contained 23.8 GHz phase locked local oscillator source. The measured level of receiver performance over the 27.3 to 30.0 GHz RF/3.7 to 6.2 GHz IF band includes 5.5 to 6.5 dB (typ) SSB noise figure, 20.5 + or - 1.5 dB conversion gain and +23 dBm minimum third order two tone intermodulation output intercept point.

  7. A broadband 47-67 GHz LNA with 17.3 dB gain in 65-nm CMOS

    Science.gov (United States)

    Chong, Wang; Zhiqun, Li; Qin, Li; Yang, Liu; Zhigong, Wang

    2015-10-01

    A broadband 47-67 GHz low noise amplifier (LNA) with 17.3 dB gain in 65-nm CMOS technology is proposed. The features of millimeter wave circuits are illustrated first and design methodologies are discussed. The wideband input matching of the LNA was achieved by source inductive degeneration, which is narrowband in the low-GHz range but wideband at millimeter-wave frequencies due to the existence of gate-drain capacitance, Cgd. In order to minimize the noise figure (NF), the LNA used a common-source (CS) structure rather than cascode in the first stage, and the noise matching principle is explored. The last two stages of the LNA used a cascode structure to increase the power gain. Analysis of the gain boost effect of the gate inductor at the common-gate (CG) transistor is also performed. T-shape matching networks between stages are intended to enlarge the bandwidth. All on-chip inductors and transmission lines are modeled and simulated with a 3-dimensional electromagnetic (EM) simulation tool to guarantee the success of the design. Measurement results show that the LNA achieves a maximum gain of 17.3 dB at 60 GHz, while the 3-dB bandwidth is 20 GHz (47-67 GHz), including the interested band of 59-64 GHz, and the minimum noise figure is 4.9 dB at 62 GHz. The LNA absorbs a current of 19 mA from a 1.2 V supply and the chip occupies an area of 900 × 550 μm2 including pads. Project supported by the National High Technology Research and Development Program of China (No. 2011AA010202).

  8. A 60-GHz interferometer with a local oscillator integrated antenna array for divertor simulation experiments on GAMMA 10/PDX

    Energy Technology Data Exchange (ETDEWEB)

    Kohagura, J., E-mail: kohagura@prc.tsukuba.ac.jp; Yoshikawa, M.; Shima, Y.; Nojiri, K.; Sakamoto, M.; Nakashima, Y. [Plasma Research Center, University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Wang, X. [Saitama University, Saitama 338-8570 (Japan); Kuwahara, D. [Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan); Ito, N. [National Institute of Technology, Ube College, Ube, Yamaguchi 755-8555 (Japan); Nagayama, Y. [National Institute of Fusion Science, Toki, Gifu 509-5292 (Japan); Mase, A. [Kyushu University, Kasuga, Fukuoka 816-8580 (Japan)

    2016-11-15

    In conventional multichannel/imaging microwave diagnostics of interferometry, reflectometry, and electron cyclotron emission measurements, a local oscillator (LO) signal is commonly supplied to a receiver array via irradiation using LO optics. In this work, we present a 60-GHz interferometer with a new eight-channel receiver array, called a local oscillator integrated antenna array (LIA). An outstanding feature of LIA is that it incorporates a frequency quadrupler integrated circuit for LO supply to each channel. This enables simple and uniform LO supply to the receiver array using only a 15-GHz LO source and a coaxial cable transmission line instead of using an expensive 60-GHz source, LO optics, and a waveguide transmission line. The new interferometer system is first applied to measure electron line-averaged density inside the divertor simulation experimental module (D-module) on GAMMA 10/PDX tandem mirror device.

  9. Complex permittivity of representative biological solutions in the 2-67 GHz range.

    Science.gov (United States)

    Zhadobov, Maxim; Augustine, Robin; Sauleau, Ronan; Alekseev, Stanislav; Di Paola, Alessandra; Le Quément, Catherine; Mahamoud, Yonis Soubere; Le Dréan, Yves

    2012-05-01

    The main purpose of this study is to provide experimental data on the complex permittivity of some biological solutions in the 2-67 GHz range at room and human body temperatures. The permittivity measurements are performed using an open-ended coaxial probe. Permittivity spectra of several representative monomolecular solutions of proteins, amino acids, nucleic acids, and carbohydrates are analyzed and compared. Furthermore, measurements have also been performed for complex biomolecular solutions, including bovine serum albumin (BSA)-DNA-glucose mixture, culture medium, and yeast extract solution. The results demonstrate that for concentrations below 1%, the permittivity spectra of the solutions do not substantially differ from that of distilled water. Measurements carried out for 4% and 20% BSA solutions show that the presence of proteins results in a decrease in permittivity. For highly concentrated RNA solutions (3%), a slight increase in the imaginary part of the permittivity is observed below 10 GHz. Experimental data show that free water permittivity can be used for modeling of the culture medium above 10 GHz. However, at lower frequencies a substantial increase in the imaginary part of the permittivity due to ionic conductivity should be carefully taken into account. A similar increase has also been observed for the yeast extract solution in the lower frequency region of the considered spectrum. Above 10 GHz, the high concentration of proteins and other low-permittivity components of the yeast extract solution results in a decrease in the complex permittivity compared to that of water. Obtained data are of utmost importance for millimeter-wave dosimetry studies.

  10. MALT90: The Millimetre Astronomy Legacy Team 90 GHz Survey

    CERN Document Server

    Jackson, J M; Foster, J B; Whitaker, J S; Sanhueza, P; Claysmith, C; Mascoop, J L; Wienen, M; Breen, S L; Herpin, F; Duarte-Cabral, A; Csengeri, T; Longmore, S; Contreras, Y; Indermuehle, B; Barnes, P J; Walsh, A J; Cunningham, M R; Brooks, K J; Britton, T R; Voronkov, M A; Urquhart, J S; Alves, J; Jordan, C H; Hill, T; Hoq, S; Finn, S; C., S; Bains, I; Bontemps, S; Bronfman, L; Caswell, J L; Deharveng, L; Ellingsen, S P; Fuller, G A; Garay, G; Green, J A; Hindson, L; Jones, P A; Lenfestey, C; Lo, N; Lowe, V; Mardones, D; Menten, K M; Minier, V; Morgan, L K; Motte, F; Muller, E; Peretto, N; Purcell, C R; Schilke, P; Schneider-Bontemps, N; Schuller, F; Titmarsh, A; Wyrowski, F; Zavagno, A

    2013-01-01

    The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass star-forming clumps. Exploiting the unique broad frequency range and on-the-fly mapping capabilities of the Australia Telescope National Facility Mopra 22 m single-dish telescope, MALT90 has obtained 3' x 3' maps toward ~2000 dense molecular clumps identified in the ATLASGAL 870 um Galactic plane survey. The clumps were selected to host the early stages of high-mass star formation and to span the complete range in their evolutionary states (from prestellar, to protostellar, and on to HII regions and photodissociation regions). Because MALT90 mapped 16 lines simultaneously with excellent spatial (38") and spectral (0.11 km/s) resolution, the data reveal a wealth of information about the clump's morphologies, chemistry, and kinematics. In this paper we outline the survey strategy, observing mode, data reduction procedure, and highlight some early science results. All MALT90 raw and p...

  11. MALT90: The Millimetre Astronomy Legacy Team 90 GHz Survey

    Science.gov (United States)

    Jackson, J. M.; Rathborne, J. M.; Foster, J. B.; Whitaker, J. S.; Sanhueza, P.; Claysmith, C.; Mascoop, J. L.; Wienen, M.; Breen, S. L.; Herpin, F.; Duarte-Cabral, A.; Csengeri, T.; Longmore, S. N.; Contreras, Y.; Indermuehle, B.; Barnes, P. J.; Walsh, A. J.; Cunningham, M. R.; Brooks, K. J.; Britton, T. R.; Voronkov, M. A.; Urquhart, J. S.; Alves, J.; Jordan, C. H.; Hill, T.; Hoq, S.; Finn, S. C.; Bains, I.; Bontemps, S.; Bronfman, L.; Caswell, J. L.; Deharveng, L.; Ellingsen, S. P.; Fuller, G. A.; Garay, G.; Green, J. A.; Hindson, L.; Jones, P. A.; Lenfestey, C.; Lo, N.; Lowe, V.; Mardones, D.; Menten, K. M.; Minier, V.; Morgan, L. K.; Motte, F.; Muller, E.; Peretto, N.; Purcell, C. R.; Schilke, P.; Bontemps, Schneider-N.; Schuller, F.; Titmarsh, A.; Wyrowski, F.; Zavagno, A.

    2013-11-01

    The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass star-forming clumps. Exploiting the unique broad frequency range and on-the-fly mapping capabilities of the Australia Telescope National Facility Mopra 22 m single-dish telescope 1 , MALT90 has obtained 3' × 3' maps towards ~2 000 dense molecular clumps identified in the ATLASGAL 870 μm Galactic plane survey. The clumps were selected to host the early stages of high-mass star formation and to span the complete range in their evolutionary states (from prestellar, to protostellar, and on to H II regions and photodissociation regions). Because MALT90 mapped 16 lines simultaneously with excellent spatial (38 arcsec) and spectral (0.11 km s-1) resolution, the data reveal a wealth of information about the clumps' morphologies, chemistry, and kinematics. In this paper we outline the survey strategy, observing mode, data reduction procedure, and highlight some early science results. All MALT90 raw and processed data products are available to the community. With its unprecedented large sample of clumps, MALT90 is the largest survey of its type ever conducted and an excellent resource for identifying interesting candidates for high-resolution studies with ALMA.

  12. All-printed diode operating at 1.6 GHz.

    Science.gov (United States)

    Sani, Negar; Robertsson, Mats; Cooper, Philip; Wang, Xin; Svensson, Magnus; Andersson Ersman, Peter; Norberg, Petronella; Nilsson, Marie; Nilsson, David; Liu, Xianjie; Hesselbom, Hjalmar; Akesso, Laurent; Fahlman, Mats; Crispin, Xavier; Engquist, Isak; Berggren, Magnus; Gustafsson, Göran

    2014-08-19

    Printed electronics are considered for wireless electronic tags and sensors within the future Internet-of-things (IoT) concept. As a consequence of the low charge carrier mobility of present printable organic and inorganic semiconductors, the operational frequency of printed rectifiers is not high enough to enable direct communication and powering between mobile phones and printed e-tags. Here, we report an all-printed diode operating up to 1.6 GHz. The device, based on two stacked layers of Si and NbSi2 particles, is manufactured on a flexible substrate at low temperature and in ambient atmosphere. The high charge carrier mobility of the Si microparticles allows device operation to occur in the charge injection-limited regime. The asymmetry of the oxide layers in the resulting device stack leads to rectification of tunneling current. Printed diodes were combined with antennas and electrochromic displays to form an all-printed e-tag. The harvested signal from a Global System for Mobile Communications mobile phone was used to update the display. Our findings demonstrate a new communication pathway for printed electronics within IoT applications.

  13. A 200-GHz telescope unit for the QUIJOTE CMB Experiment

    Science.gov (United States)

    Sanquirce, Rubén.; Etxeita, Borja; Murga, Gaizka; Fernandez, Esther; Sainz, Iñaki; Sánchez, Vicente; Viera-Curbelo, Teodora A.; Gómez, María. F.; Aguiar-Gonzalez, Marta; Hoyland, Roger J.; Pérez de Taoro, Ángeles R.; Vega, Afrodisio; Rebolo-López, Rafael; Rubiño, Jose Alberto

    2014-07-01

    Experiment QUIJOTE (Q-U-I JOint TEnerife) is a scientific collaboration, leaded by the Instituto de Astrofísica de Canarias (IAC), which can measure the polarization of the Cosmic Microwave Background (CMB) in the range of frequency up to 200 GHz, at angular scales of 1°. The project is composed of 2 telescopes and 3 instruments, located in Teide Observatory (Tenerife, Spain). After the successful delivery of the first telescope (operative since 2012), Idom is currently involved on the turn key supply of the second telescope (phase II). The work started in June 2013 and it will be completed in a challenging period of 12 months (operative at the beginning of July 2014), including design, factory assembly and testing, transport and final commissioning on site. This second unit will improve the opto-mechanical performance and maintainability. The telescope will have an unlimited rotation capacity in azimuth axis and a range of movement between 25°-95° in elevation axis. An integrated rotary joint will transmit fluid, power and signal to the rotary elements. The pointing and tracking accuracy will be significantly below to specification: 1.76 arcmin and 44 arcsec, respectively. This project completes Idoḿs contribution during phase I, which also comprises the integration and functional tests for the 5 polarimeters of the first instrument in Bilbao headquarters, and the design and supervision of the building which protects both telescopes, including the installation and commissioning of the mechanism for shutters aperture.

  14. Transport of DESY 1.3 GHZ Cryomodule at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    McGee, M.W.; Arkan, T.; Borissov, E.; Leibfritz, J.; Schappert, W.; /Fermilab; Barbanotti, S.; /LASA, Segrate /INFN, Milan

    2009-05-01

    In an exchange of technology agreement, Deutsches Elektron-Synchrotron (DESY) Laboratory in Hamburg Germany has provided a 1.3 GHz cryomodule 'kit' to Fermilab. The cryomodule components (qualified dressed cavities, cold mass parts, vacuum vessel, etc.) sent from Germany in pieces were assembled at Fermilab's Cryomodule Assembly Facility (CAF). The cavity string was assembled at CAF-MP9 Class 10 cleanroom and then transported to CAF-ICB cold mass assembly area via a flatbed air ride truck. Finite Element Analysis (FEA) studies were implemented to define location of instrumentation for initial cold mass transport, providing modal frequencies and shapes. Subsequently, the fully assembled cryomodule was transported to the SRF Accelerator Test Facility at New Muon Lab (NML). Internal geophones (velocity sensors) were attached during the coldmass assembly for transport (warm) and operational (cold) measurements. A description of the isolation system that maintained alignment during transport and protected fragile components is provided. Shock and vibration measurement results of each transport and modal analysis are discussed.

  15. Centrifugal barrel polishing of 1.3 GHz Nb cavities

    Energy Technology Data Exchange (ETDEWEB)

    Tamashevich, Yegor; Foster, Brian [DESY, Hamburg (Germany); Hamburg Univ. (Germany); Navitski, Aliaksandr; Steder, Lea; Elsen, Eckhard [DESY, Hamburg (Germany)

    2013-07-01

    Superconducting radio-frequency (SRF) cavities are the key components of particle accelerators such as the European X-ray Free Electron Laser (XFEL, under construction) and the planned future International Linear Collider (ILC). Steady progress in surface treatment techniques of SRF cavities in both the achievable quality factor Q and the accelerating electric field Eacc makes new accelerators and ambitious projects feasible. One of the alternative surface preparation techniques which is actually being explored is centrifugal barrel polishing (CBP) pioneered at KEK in Japan in mid-nineties by T. Hiuchi et al. CBP is a mechanical polishing of cavities and results in around 10 x smaller surface roughness and mirror-like surface as compared to chemistry alone. Q and E{sub acc} are expected to be at least as high as for chemically treated cavities. CBP eliminates the bulk chemistry and has the potential to completely replace the chemistry. The University of Hamburg is installing a CBP machine to study it as a cavity preparation and repair technique for 9-cell 1.3 GHz SRF cavities at the Deutsche Elektronen-Synchrotron (DESY). The setup and first commissioning tests will be presented and discussed.

  16. A 20 GHz, 75 watt, helix TWT for space communications

    Science.gov (United States)

    Heney, J. F.; Tamashiro, R. N.

    A space-qualified, helix-type traveling wave tube is being developed for satellite communication systems in the frequency band of 17.7 to 21.2 GHz. The design approach stresses very high efficiency operation, but with very low distortion. The tube provides multi-mode operation, permitting CW saturated power output levels of 75, 40, and 7.5 W. Operation is also anticipated at 5 dB below these saturation levels to achieve the required low distortion levels. Advanced construction features include a five-stage depressed collector, a diamond supported helix slow-wave circuit, and a type M dispenser cathode. High reliability and long life (10 yr) are objectives of the tube design. Preliminary test results on early developmental models of this tube are very encouraging. An output power of 75 to 90 W has been achieved over the full bandwidth with about 40 dB of saturated gain. More importantly, the basic electronic efficiency of the interaction process has been increased from about 7.5-11 percent by the use of the diamond helix support compared to earlier tubes using BeO support rods. This effort is supported by NASA Lewis Research Center and is aimed toward application in the NASA Advanced Communications Satellite Technology Program.

  17. A K-Band Push-Push VCO MMIC using embedded frequency doubling mechanism

    OpenAIRE

    Sim, Sang-Hoon; Ko, Sangsoo; Hong, Songcheol

    2004-01-01

    A K-Band Push-Push VCO MMIC which has small size, high output power and low phase noise is presented. This push-push VCO utilize the embedded frequency doubling mechanism of cross coupled topology. A commercial InGaP/GaAs HBT technology with the f T of 60 GHz and the fMAX of 110 GHz was used for the implementation. The oscillation frequency is from 21.02 GHz to 21.17 GHz. The peak output power of the VCO is 1.7dBm. The phase noise is -110dBc/Hz at 1MHz offset from 2...

  18. BICEP2 / Keck Array VI: Improved Constraints On Cosmology and Foregrounds When Adding 95 GHz Data From Keck Array

    CERN Document Server

    Array, Keck; Ade, P A R; Ahmed, Z; Aikin, R W; Alexander, K D; Barkats, D; Benton, S J; Bischoff, C A; Bock, J J; Bowens-Rubin, R; Brevik, J A; Buder, I; Bullock, E; Buza, V; Connors, J; Crill, B P; Duband, L; Dvorkin, C; Filippini, J P; Fliescher, S; Grayson, J; Halpern, M; Harrison, S; Hilton, G C; Hui, H; Irwin, K D; Karkare, K S; Karpel, E; Kaufman, J P; Keating, B G; Kefeli, S; Kernasovskiy, S A; Kovac, J M; Kuo, C L; Leitch, E M; Lueker, M; Megerian, K G; Netterfield, C B; Nguyen, H T; O'Brient, R; Ogburn, R W; Orlando, A; Pryke, C; Richter, S; Schwarz, R; Sheehy, C D; Staniszewski, Z K; Steinbach, B; Sudiwala, R V; Teply, G P; Thompson, K L; Tolan, J E; Tucker, C; Turner, A D; Vieregg, A G; Weber, A C; Wiebe, D V; Willmert, J; Wong, C L; Wu, W L K; Yoon, K W

    2016-01-01

    We present results from an analysis of all data taken by the BICEP2 & Keck Array CMB polarization experiments up to and including that taken during the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes $Q$ and $U$ in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 GHz to 353 GHz. An excess over lensed-LCDM is detected at modest significance in the 95x150 $BB$ spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23x95, or for dust/sync correlation in spectra such as 23x353. We take the likelihood of all the spectra for a multi-component model including lensed-LCDM, dust, synchrotron and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio $...

  19. The Star Formation in Radio Survey: GBT 33 GHz Observations of Nearby Galaxy Nuclei and Extranuclear Star-Forming Regions

    CERN Document Server

    Murphy, E J; Mason, B S; Condon, J J; Schinnerer, E; Aniano, G; Armus, L; Helou, G; Turner, J L; Jarrett, T H

    2012-01-01

    We present 33\\,GHz photometry of 103 galaxy nuclei and extranuclear star-forming complexes taken with the Green Bank Telescope (GBT) as part of the Star Formation in Radio Survey (SFRS). Among the sources without evidence for an AGN, and also having lower frequency radio data, we find a median thermal fraction at 33GHz of ~76% with a dispersion of ~24%. For all sources resolved on scales 90%. This suggests that the rest-frame 33GHz emission provides a sensitive measure of the ionizing photon rate from young star-forming regions, thus making it a robust star formation rate indicator. Taking the 33GHz star formation rates as a reference, we investigate other empirical calibrations relying on different combinations of warm 24\\mu m dust, total infrared (IR; 8-1000\\mu m), H\\alpha\\ line, and far-UV continuum emission. The recipes derived here generally agree with others found in the literature, albeit with a large dispersion that most likely stems from a combination of effects. Comparing the 33GHz to total IR flux ...

  20. First Season QUIET Observations: Measurements of CMB Polarization Power Spectra at 43 GHz in the Multipole Range 25 <= ell <= 475

    CERN Document Server

    Bischoff, C; Buder, I; Chinone, Y; Cleary, K; Dumoulin, R N; Kusaka, A; Monsalve, R; Næss, S K; Newburgh, L B; Reeves, R; Smith, K M; Wehus, I K; Zuntz, J A; Zwart, J T L; Bronfman, L; Bustos, R; Church, S E; Dickinson, C; Eriksen, H K; Ferreira, P G; Gaier, T; Gundersen, J O; Hasegawa, M; Hazumi, M; Huffenberger, K M; Jones, M E; Kangaslahti, P; Kapner, D J; Lawrence, C R; Limon, M; May, J; McMahon, J J; Miller, A D; Nguyen, H; Nixon, G W; Pearson, T J; Piccirillo, L; Radford, S J E; Readhead, A C S; Richards, J L; Samtleben, D; Seiffert, M; Shepherd, M C; Staggs, S T; Tajima, O; Thompson, K L; Vanderlinde, K; Williamson, R; Winstein, B

    2010-01-01

    The Q/U Imaging ExperimenT (QUIET) employs coherent receivers at 43GHz and 95GHz, operating on the Chajnantor plateau in the Atacama Desert in Chile, to measure the anisotropy in the polarization of the CMB. QUIET primarily targets the B modes from primordial gravitational waves. The combination of these frequencies gives sensitivity to foreground contributions from diffuse Galactic synchrotron radiation. Between 2008 October and 2010 December, >10,000hours of data were collected, first with the 19-element 43GHz array (3458hours) and then with the 90-element 95GHz array. Each array observes the same four fields, selected for low foregrounds, together covering ~1000deg^2. This paper reports initial results from the 43GHz receiver which has an array sensitivity to CMB fluctuations of 69uK sqrt(s). The data were extensively studied with a large suite of null tests before the power spectra, determined with two independent pipelines, were examined. Analysis choices, including data selection, were modified until th...