WorldWideScience

Sample records for fm laser radar

  1. Generating nonlinear FM chirp waveforms for radar.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2006-09-01

    Nonlinear FM waveforms offer a radar matched filter output with inherently low range sidelobes. This yields a 1-2 dB advantage in Signal-to-Noise Ratio over the output of a Linear FM waveform with equivalent sidelobe filtering. This report presents design and implementation techniques for Nonlinear FM waveforms.

  2. Analysis of chaotic FM system synchronization for bistatic radar

    Science.gov (United States)

    Pappu, Chandra S.; Verdin, Berenice; Flores, Benjamin C.; Boehm, James; Debroux, Patrick

    2015-05-01

    We propose a scheme for bistatic radar that uses a chaotic system to generate a wideband FM signal that is reconstructed at the receiver via a conventional phase lock loop. The setup for the bistatic radar includes a 3 state variable drive oscillator at the transmitter and a response oscillator at the receiver. The challenge is in synchronizing the response oscillator of the radar receiver utilizing a scaled version of the transmitted signal sr(t, x) = αst(t, x) where x is one of three driver oscillator state variables and α is the scaling factor that accounts for antenna gain, system losses, and space propagation. For FM, we also assume that the instantaneous frequency of the received signal, xs, is a scaled version of the Lorenz variable x. Since this additional scaling factor may not be known a priori, the response oscillator must be able to accept the scaled version of x as an input. Thus, to achieve synchronization we utilize a generalized projective synchronization technique that introduces a controller term -μe where μ is a control factor and e is the difference between the response state variable xs and a scaled x. Since demodulation of sr(t) is required to reconstruct the chaotic state variable x, the phase lock loop imposes a limit on the minimum error e. We verify through simulations that, once synchronization is achieved, the short-time correlation of x and xs is high and that the self-noise in the correlation is negligible over long periods of time.

  3. Modified Range-Doppler Processing for FM-CW Synthetic Aperture Radar

    NARCIS (Netherlands)

    Wit, J.J.M. de; Meta, A.; Hoogeboom, P.

    2006-01-01

    The combination of compact frequency-modulated continuous-wave (FM-CW) technology and high-resolution synthetic aperture radar (SAR) processing techniques should pave the way for the development of a lightweight, cost-effective, high-resolution, airborne imaging radar. Regarding FM-CW SAR signal pro

  4. Performance Analysis of a High Resolution Airborne FM-CW Synthetic Aperture Radar

    NARCIS (Netherlands)

    Wit, J.J.M. de; Hoogeboom, P.

    2003-01-01

    Compact FM-CW technology combined with high resolution SAR techniques should pave the way for a small and cost effective imaging radar. A research project has been inìtiated to investigate the feasibility of FM-CW SAR. Within the framework of the project an operational airborne FM-CW SAR demonstrato

  5. Detection of objects in sandy ground by an FM-CW radar

    OpenAIRE

    Yamaguchi, Y.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan); Tsurugi, M.; Watanabe, Y.; Sengoku, M.; Kikuta, T.; Nishino, M; Tsunasaki, M.; Yamaguchi, Yoshio; Sengoku, Masakazu; 山口, 芳雄; 仙石, 正和

    1993-01-01

    An FM-CW radar system for the detection of objects buried in sandy ground is explored and applied to field measurement. The key factors for underground radar performance are the center frequency and the bandwidth determining the depth at which the radar can detect targets and the resolution in the range direction, respectively. To realize a practical underground radar, two ridged horn antennas are employed in the system, which are operative in the frequency range of 250-1000 MHz. The impedanc...

  6. Experiment for buried pipes by stepped FM-CW radar; Step shiki FM-CW radar ni yoru maisetsukan tansa jikken

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, K.; Ito, M. [Kawasaki Geological Engineering, Co. Ltd., Tokyo (Japan); Tanabe, K. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1997-05-27

    The underground radar exploration is adopted to surveys of cavity under the road and buried pipes since the result of high resolution is obtained. However, the explorative depth of the radar is shallow, 2-3m in soil basement, and its applicable field has been limited. The continuous wave radar (FM-CW radar) was devised to get deeper explorative depth, but has been used for the geological structure survey such as the fault survey since it is lower in resolution as compared with the pulse radar. Therefore, to make use of characteristics of the continuous wave radar and enhance resolution in the shallow part, an experiment on buried pipes was conducted for the purpose of assessing and improving the FM-CW radar. In this processing, the wave form treatment used in the reflection method seismic survey was adopted for the radar survey. There are some problems, but it is effective to adopt the same algorithm to that used in the seismic survey to the radar exploration. The explorative depth was discussed from the damping rate of electromagnetic waves and dynamic range of facilities of the experimental site, and 7m was obtained. 5 figs., 1 tab.

  7. Multifrequency and Multistatic Inverse Synthetic Aperture Radar, with Application to FM Passive Radar

    Directory of Open Access Journals (Sweden)

    Ginolhac Guillaume

    2010-01-01

    Full Text Available This paper deals with the imaging of a moving target using a multifrequency and multistatic radar consisting in one receiver and several narrowband transmitters. Considering two hypotheses about the studied target, we derive two multistatic inverse synthetic aperture radar processors: the first one, which models the target as a set of isotropic points, performs a coherent sum of bistatic images; the second one, which models the target as a set of nonisotropic points, performs an incoherent sum of bistatic images. Numerical simulations are done, which demonstrate the efficiency of the second processor. We also apply both processors to a multistatic passive radar scenario for which the transmitters are FM stations located in a realistic configuration. We study the system performance in terms of resolution and sidelobe levels as a function of the number of transmitters and of the integration time. Both processors are applied to similar complex targets for which the scattered fields are simulated by a numerical electromagnetic code. The resulting multistatic radar images show interesting characteristics that might be used by classification algorithms in future work.

  8. Study of detection performance of passive bistatic radars based on FM broadcast

    Institute of Scientific and Technical Information of China (English)

    Shan Tao; Tao Ran; Wang Yue; Zhou Siyong

    2007-01-01

    The passive bistatic radar based on the FM broadcast has inherent superiority with respect to its survivability. In this article, the ambiguity function (AF) and the cross ambiguity function (CAF) of the FM radio signal are analyzed and illustrated.The Kolmogorov Smirnov (K-S) test verifies that the amplitude probability density function of the CAF side lobes is exponential; the distribution of the target is also deduced. Finally, the detection performance of the passive radar is studied, and the result shows that this new type bistatic radar has favorable detection capability.

  9. 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.

  10. Reduction of Surface Clutter by a Polarimetric FM-CW Radar in Underground Target Detection

    OpenAIRE

    Moriyama, Toshifumi; Yamaguchi, Yoshio; Sengoku, Masakazu; Yamada, Hiroyoshi

    1995-01-01

    This paper presents an experimental result of polarimetric detection of objects buried in a sandy ground by a synthetic aperture FM-CW radar. Emphasis is placed on the reduction of surface clutter by the polarimetric radar, which takes account of full polarimetric scattering characteristics. First, the principle of full polarimetric imaging methodology is out-lined based on the characteristic polarization states for a specific target together with a polarimetric enhancement factor which discr...

  11. Basics and first experiments demonstrating isolation improvements in the agile polarimetric FM-CW radar – PARSAX

    NARCIS (Netherlands)

    Krasnov, O.A.; Babur, G.P.; Wang, Z.; Ligthart, L.P.; Van der Zwan, F.

    2010-01-01

    The article describes the IRCTR PARSAX radar system, the S-band high-resolution Doppler polarimetric frequency modulated continuous wave (FM-CW) radar with dual-orthogonal sounding signals, which has the possibility to measure all elements of the radar target polarization scattering matrix

  12. Noise analysis for near field 3-D FM-CW radar imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Sheen, David M.

    2015-06-19

    Near field radar imaging systems are used for several applications including concealed weapon detection in airports and other high-security venues. Despite the near-field operation, phase noise and thermal noise can limit the performance in several ways including reduction in system sensitivity and reduction of image dynamic range. In this paper, the effects of thermal noise, phase noise, and processing gain are analyzed in the context of a near field 3-D FM-CW imaging radar as might be used for concealed weapon detection. In addition to traditional frequency domain analysis, a time-domain simulation is employed to graphically demonstrate the effect of these noise sources on a fast-chirping FM-CW system.

  13. Research on Doppler frequency in incoherent FM/CW laser detection

    Science.gov (United States)

    Liu, Kai; Cui, Zhanzhong

    2010-10-01

    The principle of transmitted and received laser in incoherent FM/CW laser detection is different from the one in coherent FM/CW laser detection. The methods for distance solution in both detections are similar. Incoherent FM/CW laser detection uses subcarrier to modulate the intensity of laser, and the photodetector detects the intensity of received signal. The amplified photocurrent is mixed with local oscillator signal, and the intermediate frequency (IF) signal contains the information of distance from sensor to target. The Doppler frequency for this detection is related with the relative radial velocity between sensor and target. The optical frequency is directly modulated with electro-optic device in coherent FM/CW laser detection and the received laser signal is photomixed with transmitted laser signal. The Doppler frequency in the detection relates to the optical frequency. In distance-measuring lidar, the Doppler frequency affects the solution. The Doppler frequency in incoherent FM/CW laser detection is unrelated with optical frequency, and it is much less than the one in coherent FM/CW laser detection, correspondingly. The error in incoherent FM/CW laser detection is smaller. As a result, the incoherent FM/CW laser detection is more suitable for the use of distance-measuring lidar.

  14. Numerical simulation of imaging laser radar system

    Science.gov (United States)

    Han, Shaokun; Lu, Bo; Jiang, Ming; Liu, Xunliang

    2008-03-01

    Rational and effective design of imaging laser radar systems is the key of imaging laser radar system research. Design must fully consider the interrelationship between various parameters. According to the parameters, choose suitable laser, detector and other components. To use of mathematical modeling and computer simulation is an effective imaging laser radar system design methods. This paper based on the distance equation, using the detection statistical methods, from the laser radar range coverage, detection probability, false-alarm rate, SNR to build the laser radar system mathematical models. In the process of setting up the mathematical models to fully consider the laser, atmosphere, detector and other factors on the performance that is to make the models be able to respond accurately the real situation. Based on this using C# and Matlab designed a simulation software.

  15. Micro pulse laser radar

    Science.gov (United States)

    Spinhirne, James D. (Inventor)

    1993-01-01

    An eye safe, compact, solid state lidar for profiling atmospheric cloud and aerosol scattering is disclosed. The transmitter of the micro pulse lidar is a diode pumped micro-J pulse energy, high repetition rate Nd:YLF laser. Eye safety is obtained through beam expansion. The receiver employs a photon counting solid state Geiger mode avalanche photodiode detector. Data acquisition is by a single card multichannel scaler. Daytime background induced quantum noise is controlled by a narrow receiver field-of-view and a narrow bandwidth temperature controlled interference filter. Dynamic range of the signal is limited to optical geometric signal compression. Signal simulations and initial atmospheric measurements indicate that micropulse lider systems are capable of detecting and profiling all significant cloud and aerosol scattering through the troposphere and into the stratosphere. The intended applications are scientific studies and environmental monitoring which require full time, unattended measurements of the cloud and aerosol height structure.

  16. [IM/FM phase delay time measurement method of laser for TDLAS].

    Science.gov (United States)

    Zhang, Chao; Ma, Wei-Guang

    2014-11-01

    The present paper presents an method of using fiber Michelson interferometer to measure the Intensity-frequency (IM/FM) phase delay change of the laser, it could realize the phase delay time measurement, while modulating the laser. Experimental results show that the laser output signal intensity-frequency (IM/FM) phase delay of the laser has some differences from the theoretical value. The proposed method can be used to compensate for real-time signal strength-frequency (IM/FM) phase delay effect on the gas concentration measurement results.

  17. Remote sensing with laser spectrum radar

    Science.gov (United States)

    Wang, Tianhe; Zhou, Tao; Jia, Xiaodong

    2016-10-01

    The unmanned airborne (UAV) laser spectrum radar has played a leading role in remote sensing because the transmitter and the receiver are together at laser spectrum radar. The advantages of the integrated transceiver laser spectrum radar is that it can be used in the oil and gas pipeline leak detection patrol line which needs the non-contact reflective detection. The UAV laser spectrum radar can patrol the line and specially detect the swept the area are now in no man's land because most of the oil and gas pipelines are in no man's land. It can save labor costs compared to the manned aircraft and ensure the safety of the pilots. The UAV laser spectrum radar can be also applied in the post disaster relief which detects the gas composition before the firefighters entering the scene of the rescue.

  18. Digital Receiver for Laser Imaging Radar

    Institute of Scientific and Technical Information of China (English)

    WANG Wei Ran; SUN Bing

    2004-01-01

    With the extension of the application domains for laser imaging radar,it is necessary to find a new technical way to obtain high technical performance and adaptive ability.In this paper,A new concept of digital receiver of laser imaging radar system is presented.This digital receiver is defined as a time varying parameter receiver which possesses large dynamics region and time domain filter.The receiver's mode,component structure as well as every function of its processing are described.The results and laboratorial data show the feasibility of digital reception.Also,it can exploit the inherent nature of laser imaging radar to obtain high probability of detection.

  19. High accuracy 3-D laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a mono-static staring 3-D laser radar based on gated viewing with range accuracy below 1 m at 10 m and 1 cm at 100. We use a high sensitivity, fast, intensified CCD camera, and a Nd:Yag passively Q-switched 32.4 kHz pulsed green laser at 532 nm. The CCD has 752x582 pixels. Camera...

  20. Influences of weather phenomena on automotive laser radar systems

    Science.gov (United States)

    Rasshofer, R. H.; Spies, M.; Spies, H.

    2011-07-01

    Laser radar (lidar) sensors provide outstanding angular resolution along with highly accurate range measurements and thus they were proposed as a part of a high performance perception system for advanced driver assistant functions. Based on optical signal transmission and reception, laser radar systems are influenced by weather phenomena. This work provides an overview on the different physical principles responsible for laser radar signal disturbance and theoretical investigations for estimation of their influence. Finally, the transmission models are applied for signal generation in a newly developed laser radar target simulator providing - to our knowledge - worldwide first HIL test capability for automotive laser radar systems.

  1. Laser radar monitoring of tropospheric aerosols

    Science.gov (United States)

    Devara, P. C. S.; Raj, P. Ernest; Londhe, A. L.

    1989-04-01

    A bistatic laser radar (using a continuous wave argon ion laser) installed at the Indian Institute of Tropical Meteorology (IITM), Pune, for remote sounding of atmospheric aerosol characteristics has been briefly described. The day-to-day and height-time variations in the vertical distribution of aerosol number density (up to 3680 m AGL) have been studied by operating the radar on 6 clear days during nighttime in the month of April 1987. The results of the study indicated the formation and redistribution of aerosol layer structure in the lower altitudes (up to 1800 m). Also, conspicuous differences in the height distribution of aerosol number density were noticed between the post-sunset and pre-sunrise periods. The observed features have been explained on the basis of aerosol transport and diffusion processes occurring in the nocturnal urban atmosphere.

  2. 18th International Laser Radar Conference

    CERN Document Server

    Neuber, Roland; Rairoux, Patrick; Wandinger, Ulla

    1997-01-01

    Lidar or laser radar, the depth-resolved remote measurement of atmospheric parameters with optical means, has become an important tool in the field of atmospheric and environmental remote sensing. In this volume the latest progress in the development of lidar methods, experiments, and applications is described. The content is based on selected and thoroughly refereed papers presented at the 18th International Laser Radar Conference, Berlin, 22-26 July 1996. The book is divided into six parts which cover the topics of tropospheric aerosols and clouds, lidar in space, wind, water vapor, troposheric trace gases and plumes, and stratospheric and mesospheric profiling. As a supplement to fundamental lidar textbooks this volume may serve as a guide for scientists, engineers, and graduate students through the blossoming field of modern lidar techniques and their contribution to atmospheric and environmental research.

  3. Study on moving target detection to passive radar based on FM broadcast transmitter

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Target detection by a noncooperative illuminator is a topic of general interest in the electronic warfare field.First of all,direct-path interference(DPI)suppression which is the technique of bottleneck of moving target detection by a noncooperative frequency modulation(FM) broadcast transmitter is analyzed in this article;Secondly,a space-time-frequency domain synthetic solution to this problem is introduced:Adaptive nulling array processing is considered in the space domain,DPI cancellation based on adaptive fractional delay interpolation(AFDI)technique is used in planned time domain,and long-time coherent integration is utilized in the frequency domain;Finally,an experimental system is planned by considering FM broadcast transmitter as a noncooperative illuminator,Simulation results by real collected data show that the proposed method has a better performance of moving target detection.

  4. High accuracy 3-D laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a mono-static staring 3-D laser radar based on gated viewing with range accuracy below 1 m at 10 m and 1 cm at 100. We use a high sensitivity, fast, intensified CCD camera, and a Nd:Yag passively Q-switched 32.4 kHz pulsed green laser at 532 nm. The CCD has 752x582 pixels. Camera...... shutter is controlled in steps of 100 ps. Camera delay is controlled in steps of 100 ps. Each laser pulse triggers the camera delay and shutter. A 3-D image is constructed from a sequence of 50-100 2-D reflectivity images, where each frame integrates about 700 laser pulses on the CCD. In 50 Hz video mode...

  5. Data processing in a FM-CW radar system for ionospheric drift measurements by means of partial reflections

    Science.gov (United States)

    Hoffmann, P.; Keuer, D.; Singer, W.; Linow, Th.

    The determination of the horizontal component of the ionospheric wind at the height range of 60-90 km is carried out by the spaced antenna drift method. The FM-CW radar system installed at Juliusruh (54.6 N; 13.4 E) is working with a center frequency of 3.18 MHz and permits a height resolution of 1.5km. During each measuring cycle 16 adjacent height channels are processed. Due to the large amount of primary data as well as a high resolution in time of wind values the data processing including the derivation of wind profiles must be carried out at real-time conditions. A resolution in time of 5 min is intended.

  6. Development of an airborne MMW FM-CW radar for mapping river ice

    Science.gov (United States)

    Yankielum, Norbert E.; Ferrick, Michael G.; Weyrick, Patricia B.

    1993-01-01

    Analyses of a river's freezeup ice cover stability and its breakup rely on detailed knowledge of the cover's thickness and the variability of that thickness. A high-resolution, millimeter wave (26.5- to 40-GHz) Frequency Modulated-Continuous Wave radar with real-time data acquisition and digital signal processing and display capability was deployed from a low-flying (3-10 m) helicopter to continuously acquire, process and display data during an ice thickness profiling survey of a 24-km study reach. A nominal sheet ice thickness of 50 cm, occasional areas of new ice sheet as thin as 5 cm, open leads, and massive ice accumulations on the order of 5 m thick were encountered. Radar profiling data agreed with ground truth from borehole measurements of the sheet ice, and provided a more detailed view of the ice conditions than that obtained from a low altitude video survey. The radar system provided rapid, safe and accurate data acquisition, allowing detailed mapping of the ice conditions throughout the reach.

  7. Application Research on Space Laser Communication in Bistatic Radar System

    Institute of Scientific and Technical Information of China (English)

    李晓萍; 韩绍坤; 郝小宁

    2003-01-01

    There exist three synchronizing problems in the bistatic radar system that some signals of the radar receiver must be synchronized with those of the radar transmitter. Several methods realizing data transmission, which are used to complete the synchronization existing in the bistatic radar system, are described. Then a new idea is brought forward that employs space laser communication in the bistatic radar system to realize its data transmission. The theoretic analysis of the idea's usability and its merits are discussed in details. Finally the latest development of space laser communication is introduced, and the utility of the idea is pointed out further.

  8. Study on Effectiveness of the chaos laser radar

    OpenAIRE

    2003-01-01

    A laser is widely applied for measurements, since it is invented. There are two types of laser distance meter for short and long distance. For long distance, a laser radar using propagation time of laser light is used. Generally, a distance is measured from delay time using either a periodic signal or a single pulse. But the signal becomes to be buried in noise with increasing distance. A new type of chaos laser radar which processes by only an addition is proposed. This radar can quickly pro...

  9. FM-CW radar sensors for vital signs and motor activity monitoring

    Directory of Open Access Journals (Sweden)

    Octavian Adrian Postolache

    2011-12-01

    Full Text Available The article summarizes on-going research on vital signs and motor activity monitoring based on radar sensors embedded in wheelchairs, walkers and crutches for in home rehabilitation. Embedded sensors, conditioning circuits, real-time platforms that perform data acquisition, auto-identification, primary data processing and data communication contribute to convert daily used objects in home rehabilitation into smart objects that can be accessed by caregivers during the training sessions through human–machine interfaces expressed by the new generation of smart phones or tablet computers running Android OS or iOS operating systems. The system enables the management of patients in home rehabilitation by providing more accurate and up-to-date information using pervasive computing of vital signs and motor activity records.

  10. Effect of low level laser on ototoxicity prevention of FM1-43 in postnatal organotypic culture of rat utricles

    Science.gov (United States)

    Chung, Yong Won; Kim, Yong Saeng; Ahn, Jin-Chul; Chung, Phil-Sang; Rhee, Chung-Ku

    2007-02-01

    Backgrounds and Objectives: The styryl pyridinium dye FM1-43 is nontoxic, fluorescent, cationic dye whose fluorescence markedly increases after partitioning into membrane. Rapid entry of FM1-43 is inhibited by drugs that block the mechanically gated transduction channels, suggesting the dye can itself act as a permanent blocker of the channels. In this study, the effects of low level laser (LLL) and FM1-43 on gentiamicin induced ototoxicity in postnatal organotypic culture of rat utricles were investigated. Materials and Methods: An organotypic culture of 2- 7-day-old rat utricular maculae was established. In a series of experiments utricles were exposed to either irradiation of low level laser(LG group)or 10 ?M FM1-43(FG group) or both(LFG group) followed by 1mM of gentamicin treatment for 12 hrs. The results of experimental groups were compared with the control group by confocal laser scanning and scanning electron microscopy. Results: LLL prevented vestibular hair cells ototoxicity. Rapid incubation with FM1-43 dye protected vestibular hair cell damage induced by gentamicin treatment. Substantial additive effect of LLL on ototoxicity prevention was noted in combination therapy with FM1-43. There were statistical significant differences among all groups but between control and LFG group by both confocal laser scanning and scanning electron microscopy. In addition, caspase-3 activity was hardly found in LFG group after double staining with Phalloidin-FITC by confocal laser scanning microscopy. Conclusion: These results suggest that there is an additive protection effect of LLL and FM1-43 against gentamicin ototoxicity in postnatal organotypic culture of rat utricles. LLL may have clinical preventive and therapeutic implications on ototoxicity.

  11. Coherent Doppler Laser Radar: Technology Development and Applications

    Science.gov (United States)

    Kavaya, Michael J.; Arnold, James E. (Technical Monitor)

    2000-01-01

    NASA's Marshall Space Flight Center has been investigating, developing, and applying coherent Doppler laser radar technology for over 30 years. These efforts have included the first wind measurement in 1967, the first airborne flights in 1972, the first airborne wind field mapping in 1981, and the first measurement of hurricane eyewall winds in 1998. A parallel effort at MSFC since 1982 has been the study, modeling and technology development for a space-based global wind measurement system. These endeavors to date have resulted in compact, robust, eyesafe lidars at 2 micron wavelength based on solid-state laser technology; in a factor of 6 volume reduction in near diffraction limited, space-qualifiable telescopes; in sophisticated airborne scanners with full platform motion subtraction; in local oscillator lasers capable of rapid tuning of 25 GHz for removal of relative laser radar to target velocities over a 25 km/s range; in performance prediction theory and simulations that have been validated experimentally; and in extensive field campaign experience. We have also begun efforts to dramatically improve the fundamental photon efficiency of the laser radar, to demonstrate advanced lower mass laser radar telescopes and scanners; to develop laser and laser radar system alignment maintenance technologies; and to greatly improve the electrical efficiency, cooling technique, and robustness of the pulsed laser. This coherent Doppler laser radar technology is suitable for high resolution, high accuracy wind mapping; for aerosol and cloud measurement; for Differential Absorption Lidar (DIAL) measurements of atmospheric and trace gases; for hard target range and velocity measurement; and for hard target vibration spectra measurement. It is also suitable for a number of aircraft operations applications such as clear air turbulence (CAT) detection; dangerous wind shear (microburst) detection; airspeed, angle of attack, and sideslip measurement; and fuel savings through

  12. Suppression of FM-to-AM modulation by polarizing fiber front end for high-power lasers.

    Science.gov (United States)

    Qiao, Zhi; Wang, Xiaochao; Fan, Wei; Li, Xuechun; Jiang, Youen; Li, Rao; Huang, Canhong; Lin, Zunqi

    2016-10-10

    FM-to-AM modulation is an important effect in the front end of high-power lasers that influences the temporal profile. Various methods have been implemented in standard-fiber and polarization-maintaining (PM)-fiber front ends to suppress the FM-to-AM modulation. To analyze the modulation in the front end, a theoretical model is established and detailed simulations carried out that show that the polarizing (PZ) fiber, whose fast axis has a large loss, can successfully suppress the modulation. Moreover, the stability of the FM-to-AM modulation can be improved, which is important for the front end to obtain a stable output. To verify the model, a PZ fiber front end is constructed experimentally. The FM-to-AM modulation, without any compensation, is less than 4%, whereas that of the PM fiber front end with the same structure is nearly 20%. The stability of the FM-to-AM modulation depth is analyzed experimentally and the peak-to-peak and standard deviation (SD) are 2% and 0.38%, respectively, over 3 h. The experimental results agree with the simulation results and both prove that the PZ fiber front end can successfully suppress the FM-to-AM conversion. The PZ fiber front end is a promising alternative for improving the performance of the front end in high-power laser facilities.

  13. Laser Radar Receiver Performance Improvement by Inter Symbol Interference

    Science.gov (United States)

    Mao, Xuesong; Inoue, Daisuke; Matsubara, Hiroyuki; Kagami, Manabu

    The power of laser radar received echoes varies over a large range due to many factors such as target distance, size, reflection ratio, etc, which leads to the difficulty of decoding codes from the received noise buried signals for spectrum code modulated laser radar. Firstly, a pseudo-random noise (PN) code modulated laser radar model is given, and the problem to be addressed is discussed. Then, a novel method based on Inter Symbol Interference (ISI) is proposed for resolving the problem, providing that only Additive White Gaussian Noise (AWGN) exists. The ISI effect is introduced by using a high pass filter (HPF). The results show that ISI improves laser radar receiver decoding ratio, thus the peak of the correlation function of decoded codes and modulation codes. Finally, the effect of proposed method is verified by a simple experiment.

  14. Study on improvement in distance accuracy of the chaos laser radar

    OpenAIRE

    2007-01-01

    As one of the in-car radar, a laser radar is widely studied. Since the laser radar has a characteristic that the received signal becomes to be buried in noise with increasing distance, it needs high power laser.Then, a new type oof the chao laser radar has been stuied.Using chaos signal for the transmitted signal,this laser radar is relatively resistant to noise and can simply process because of using only additional process However, a distance resolution of the chaos laser radar is limited ...

  15. Laser radar technology and applications; Proceedings of the Meeting, Quebec, Canada, June 3-5, 1986

    Science.gov (United States)

    Cruickshank, James M.; Harney, Robert C.

    1986-01-01

    Various papers on laser radar technology and applications are presented. The topics considered include: eye-safe solid lasers for lidar applications, practical DF laser for ranging applications, ultrafast surface barrier photodetectors, performance analyses for peak-detecting laser radars, multiple scattering for laser beams propagating in a layered atmosphere, laser radar cross section of objects immersed in the earth's atmosphere, measurements of pulse coherence in mode-locked TEA-CO2 lasers, and single longitudinal mode operation of a continuously tunable high pressure TE-CO2. Also discussed are: amplitude-modulated laser system for distance and displacement measurement, minilaser rangefinder, laser docking system radar flight experiment, improved optical resonator for laser radars, design of frequency-stable TEA-CO2 lasers, HgCdTe photodiodes for heterodyne applications, acoustooptic spectrum analyzer for laser radar applications, laser cloud mapper and its applications, scanning lidar bathymeter for water depth measurement, and fluorescence lidar for land and sea remote sensing.

  16. Coherent laser radar at 3.6 microm.

    Science.gov (United States)

    Hanson, Frank; Lasher, Mark

    2002-12-20

    Coherent laser radar systems in the mid-IR wavelength region can have advantages in low-altitude environment because they are less sensitive to scattering, turbulence, and humidity, which can affect shorter- or longer-wavelength system. We describe a coherent laser radar at 3.6 microm based on a single-frequency optical parametric oscillator and demonstrate the system over short ranges outdoors. The system was used to make micro-Doppler measurements from idling trucks that were processed to give surface vibration spectra.

  17. A Cramer Rao analysis on receiver placement in a FM band commensal radar system based on doppler only measurements

    CSIR Research Space (South Africa)

    Maasdorp, FDV

    2014-10-01

    Full Text Available This paper investigates the theoretical placement of receivers in an Commensal Radar (CR), Doppler only tracking system with a single transmitter multiple receiver configuration. Theory, based on the Fisher Information matrix (FIM), is developed...

  18. Application of laser radar to autonomous spacecraft landing

    Science.gov (United States)

    Gleichman, Kurt; Tchoryk, Peter, Jr.; Sampson, Robert E.

    1991-01-01

    This paper discusses the scenario of an autonomous landing like that required for the Mars Rover Sample Return Mission. An application of laser radar for conducting autonomous hazard detection and avoidance is discussed. A trade-study is performed to identify operational and implementation constraints as well as the state of the art in component technology.

  19. Clutter discrimination algorithm simulation in pulse laser radar imaging

    Science.gov (United States)

    Zhang, Yan-mei; Li, Huan; Guo, Hai-chao; Su, Xuan; Zhu, Fule

    2015-10-01

    Pulse laser radar imaging performance is greatly influenced by different kinds of clutter. Various algorithms are developed to mitigate clutter. However, estimating performance of a new algorithm is difficult. Here, a simulation model for estimating clutter discrimination algorithms is presented. This model consists of laser pulse emission, clutter jamming, laser pulse reception and target image producing. Additionally, a hardware platform is set up gathering clutter data reflected by ground and trees. The data logging is as clutter jamming input in the simulation model. The hardware platform includes a laser diode, a laser detector and a high sample rate data logging circuit. The laser diode transmits short laser pulses (40ns FWHM) at 12.5 kilohertz pulse rate and at 905nm wavelength. An analog-to-digital converter chip integrated in the sample circuit works at 250 mega samples per second. The simulation model and the hardware platform contribute to a clutter discrimination algorithm simulation system. Using this system, after analyzing clutter data logging, a new compound pulse detection algorithm is developed. This new algorithm combines matched filter algorithm and constant fraction discrimination (CFD) algorithm. Firstly, laser echo pulse signal is processed by matched filter algorithm. After the first step, CFD algorithm comes next. Finally, clutter jamming from ground and trees is discriminated and target image is produced. Laser radar images are simulated using CFD algorithm, matched filter algorithm and the new algorithm respectively. Simulation result demonstrates that the new algorithm achieves the best target imaging effect of mitigating clutter reflected by ground and trees.

  20. Antenna array characterisation and signal processing for an FM radio-based passive coherent location radar system

    NARCIS (Netherlands)

    Belfiori, F.; Monni, S.; Rossum, W.L. van; Hoogeboom, P.

    2012-01-01

    The design of passive coherent location radar, which exploits broadcasting transmitters of opportunity in the very high frequency (VHF) radio bandwidth, is presented. Here, the authors primarily focus on the system set-up and on the digital pre-processing steps. Emphasis is given to the antenna sect

  1. Three-dimensional environment models from airborne laser radar data

    Science.gov (United States)

    Soderman, Ulf; Ahlberg, Simon; Elmqvist, Magnus; Persson, Asa

    2004-09-01

    Detailed 3D environment models for visualization and computer based analyses are important in many defence and homeland security applications, e.g. crisis management, mission planning and rehearsal, damage assessment, etc. The high resolution data from airborne laser radar systems for 3D sensing provide an excellent source of data for obtaining the information needed for many of these models. To utilise the 3D data provided by the laser radar systems however, efficient methods for data processing and environment model construction needs to be developed. In this paper we will present some results on the development of laser data processing methods, including methods for data classification, bare earth extraction, 3D-reconstruction of buildings, and identification of single trees and estimation of their position, height, canopy size and species. We will also show how the results can be used for the construction of detailed 3D environment models for military modelling and simulation applications. The methods use data from discrete return airborne laser radar systems and digital cameras.

  2. Study on on-line processing of the chaos laser radar using FPGA

    OpenAIRE

    2005-01-01

    Today, a car industry puts effort into making intelligent car to realize a safe and comfortable car society. As one of the sensing technology, laser radar is widely studied as in-car radar. The received signal in the laser radar becomes to be buried in noise with increasing distance. When the long distance is measured, it needs a high power laser, or the repetitive process that uses multiplication and integration. Therefore, a new type of the chaos laser radar has been studied. This laser rad...

  3. Fusing Laser and Radar Data for Enhanced Situation Awareness

    OpenAIRE

    Eliasson, Emanuel

    2010-01-01

    With an increasing traffic intensity the demands on vehicular safety is higher than ever before. Active safety systems that have been developed recent years are a response to that. In this master thesis Sensor Fusion is used to combine information from a laser scanner and a microwave radar in order to get more information about the surroundings in front of a vehicle. The Extended Kalman Filter method has been used to fuse the information from the sensors. The process model consists partly of ...

  4. Ground Object Recognition using Laser Radar Data : Geometric Fitting, Performance Analysis, and Applications

    OpenAIRE

    Grönwall, Christna

    2006-01-01

    This thesis concerns detection and recognition of ground object using data from laser radar systems. Typical ground objects are vehicles and land mines. For these objects, the orientation and articulation are unknown. The objects are placed in natural or urban areas where the background is unstructured and complex. The performance of laser radar systems is analyzed, to achieve models of the uncertainties in laser radar data. A ground object recognition method is presented. It handles general,...

  5. Research and development of laser radar for environmental measurement. 2; Kankyo keisokuyo laser radar no kenkyu kaihatsu. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This project was received by Optoelectronic Industry and Technology Development Association from NEDO, and aims to contribute to the improvement of Indonesia's environmental administration through the development of an air pollution observing laser radar (LR) and of an environmental information network system fit for use in the country in cooperation with Indonesian engineers. LRs will be installed at several sites in an urban area where environmental problems are increasingly serious, and a observation network system will be constructed to link the laser radar sites. The observed data will be collected, analyzed, and processed by an observation data processing center for the investigation of the three-dimensional spatial distribution of air pollution to determine the actual state of air pollution over an urban area. The laser radars and the network will be placed in the city of Djakarta. The Indonesian authority responsible for the project is Indonesian Institute of Sciences. In fiscal 1994, part of the equipment (difference absorbing LR) was designed and manufactured, the design of the environmental information network system was developed, and various researches required in this connection were conducted. (NEDO)

  6. Optical smoothing of laser imprinting in planar-target experiments on OMEGA EP using multi-FM 1-D smoothing by spectral dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Hohenberger, M., E-mail: mhoh@lle.rochester.edu; Shvydky, A.; Marozas, J. A.; Bonino, M. J.; Canning, D.; Collins, T. J. B.; Dorrer, C.; Kessler, T. J.; Kruschwitz, B. E.; McKenty, P. W.; Regan, S. P.; Sangster, T. C.; Zuegel, J. D. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road Rochester, Rochester, New York 14623 (United States); Fiksel, G. [Nuclear Engineering and Radiological Sciences (NERS), University of Michigan, Ann Arbor, Michigan 48109 (United States); Meyerhofer, D. D. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2016-09-15

    Direct-drive ignition on the National Ignition Facility (NIF) requires single-beam smoothing to minimize imprinting of laser nonuniformities that can negatively affect implosion performance. One-dimensional, multi-FM smoothing by spectral dispersion (SSD) has been proposed to provide the required smoothing [Marozas et al., Bull. Am. Phys. Soc. 55, 294 (2010)]. A prototype multi-FM SSD system has been integrated into the NIF-like beamline of the OMEGA EP Laser System. Experiments have been performed to verify the smoothing performance by measuring Rayleigh–Taylor growth rates in planar targets of laser-imprinted and preimposed surface modulations. Multi-FM 1-D SSD has been observed to reduce imprint levels by ∼50% compared to the nominal OMEGA EP SSD system. The experimental results are in agreement with 2-D DRACO simulations using realistic, time-dependent far-field spot-intensity calculations that emulate the effect of SSD.

  7. Optical smoothing of laser imprinting in planar-target experiments on OMEGA EP using multi-FM 1-D smoothing by spectral dispersion

    Science.gov (United States)

    Hohenberger, M.; Shvydky, A.; Marozas, J. A.; Fiksel, G.; Bonino, M. J.; Canning, D.; Collins, T. J. B.; Dorrer, C.; Kessler, T. J.; Kruschwitz, B. E.; McKenty, P. W.; Meyerhofer, D. D.; Regan, S. P.; Sangster, T. C.; Zuegel, J. D.

    2016-09-01

    Direct-drive ignition on the National Ignition Facility (NIF) requires single-beam smoothing to minimize imprinting of laser nonuniformities that can negatively affect implosion performance. One-dimensional, multi-FM smoothing by spectral dispersion (SSD) has been proposed to provide the required smoothing [Marozas et al., Bull. Am. Phys. Soc. 55, 294 (2010)]. A prototype multi-FM SSD system has been integrated into the NIF-like beamline of the OMEGA EP Laser System. Experiments have been performed to verify the smoothing performance by measuring Rayleigh-Taylor growth rates in planar targets of laser-imprinted and preimposed surface modulations. Multi-FM 1-D SSD has been observed to reduce imprint levels by ˜50% compared to the nominal OMEGA EP SSD system. The experimental results are in agreement with 2-D DRACO simulations using realistic, time-dependent far-field spot-intensity calculations that emulate the effect of SSD.

  8. Real-time characterization of FM-AM modulation in a high-power laser facility using an RF-photonics system and a denoising algorithm.

    Science.gov (United States)

    Huang, Canhong; Lu, Xinghua; Jiang, Youen; Wang, Xiaochao; Qiao, Zhi; Fan, Wei

    2017-02-20

    FM-AM modulation of high-power lasers significantly affects laser performance. Therefore, precise measurement of the FM-AM modulation depth is necessary. The subsequent FM-AM modulation generated by group velocity dispersion when the laser pulse propagates through a fiber affects the measurement accuracy. In order to eliminate this effect, a waveform-acquisition module is proposed that converts a broad-spectrum pulse of 1053 nm to a narrow-spectrum pulse of 1550 nm, without affecting the waveform. In addition, a signal-processing algorithm based on the orthogonal matching pursuit method is implemented to remove the sampling noise from the waveform. In this way, the signal-to-noise ratio of the measurement can be readily improved. Both theoretical and experimental results indicate that the proposed FM-AM modulation detection system is effective and economical. It can measure the FM-AM modulation depth precisely, and therefore shows considerable promise for future applications in high-power lasers.

  9. Optical identification of sea-mines - Gated viewing three-dimensional laser radar

    DEFF Research Database (Denmark)

    Busck, Jens

    2005-01-01

    A gated viewing high accuracy mono-static laser radar has been developed for the purpose of improving the optical underwater sea-mine identification handled by the Navy. In the final stage of the sea-mine detection, classification and identification process the Navy applies a remote operated...... vehicle for optical identification of the bottom seamine. The experimental results of the thesis indicate that replacing the conventional optical video and spotlight system applied by the Navy with the gated viewing two- and three-dimensional laser radar can improve the underwater optical sea......-mine identification. The laser radar has also a number of applications on land, for example, face recognition at several hundred meters range. The main components of the laser radar system are a green pulsed laser and a fast gating intensified CCD camera. The laser radar system innovation is a combination...

  10. Coherent Laser Radar Metrology System for Large Scale Optical Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new type of laser radar metrology inspection system is proposed that incorporates a novel, dual laser coherent detection scheme capable of eliminating both...

  11. Coherent Laser Radar Metrology System for Large Scale Optical Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A new type of laser radar metrology inspection system is proposed that incorporates a novel, dual laser coherent detection scheme capable of eliminating both...

  12. FM Interference Suppression for PRC-CW Radar Based on ASTFT and Median Filtering%基于ASTFT和中值滤波的PRC-CW雷达FM干扰抑制方法

    Institute of Scientific and Technical Information of China (English)

    陈文武; 蔡征宇; 陈如山

    2011-01-01

    The influence of frequency modulation (FM) interference on correlation detection performance of the pseudo random code continuous wave( PRC-CW )radar is analyzed. It is found that the correlation output deteriorates greatly when the FM interference power exceeds the antijamming limitation of the radar. According to the fact that the PRC-CW radar return signal is a wideband pseudo random signal occupying the whole time-frequency(TF) plane,whereas the FM interference signal is well concentrated in the TF plane, a new method is proposed based on adaptive short-time Fourier transform (ASTIr) and median filtering for FM interference suppression. This method implements the filtering of the received signal by substituting the median filter output for only a portion of the IF plane corrupted by the interference. The echo signals corrupted by two types of interferences including linear FM ( LFM ) and sinusoidal FM ( SFM ) forms under different signal-tojamming ratio(SJR) situations are simulated. It is shown that the method can effectively suppress the FM interference and improve the performance of target detection significantly.%通过分析调频(FM)干扰对伪码调相连续波雷达相关检测性能的影响,发现当FM干扰超出伪码调相雷达自身抗干扰容限时,相关输出严重恶化.针对该问题,考虑到伪码在时频平面上是近似均匀和平坦的,而FM干扰则具有较好的时频聚集性,该文提出了基于自适应短时傅里叶变换(ASTFT)和中值滤波的FM干扰抑制方法.该方法通过对时频平面上被干扰污染的部分进行中值滤波,实现了对FM干扰的抑制.对不同信干比情况下线性调频和正弦调频干扰抑制前后的相关输出进行了仿真分析.结果表明,该方法能够有效抑制干扰,使相关输出得到显著改善.

  13. Modulated laser radar decoding by inter symbol interference

    Science.gov (United States)

    Mao, Xuesong; Inoue, Daisuke; Matsubara, Hiroyuki; Kagami, Manabu

    2011-03-01

    Pseudo Random Noise (PN) coded laser radar can improve the target detection ability without the demand on high power laser. However, the reflected echoes are generally so weak that they are buried in the thermal noise of the receiver, which raises the problem of choosing an optimal threshold for correctly decoding them since the power of echoes varies from time to time, and the voltage of light generated electrical signal by photo diode (PD) is always positive. In this work, we firstly show the problem we are going to discuss. Then, a novel method basing on Inter Symbol Interference (ISI) is proposed for solving the problem. Next, numerical simulations and experiments are performed to validate the method. Finally, we discuss the obtained results theoretically.

  14. Agile beam laser radar using computational imaging for robotic perception

    Science.gov (United States)

    Powers, Michael A.; Stann, Barry L.; Giza, Mark M.

    2015-05-01

    This paper introduces a new concept that applies computational imaging techniques to laser radar for robotic perception. We observe that nearly all contemporary laser radars for robotic (i.e., autonomous) applications use pixel basis scanning where there is a one-to-one correspondence between world coordinates and the measurements directly produced by the instrument. In such systems this is accomplished through beam scanning and/or the imaging properties of focal-plane optics. While these pixel-basis measurements yield point clouds suitable for straightforward human interpretation, the purpose of robotic perception is the extraction of meaningful features from a scene, making human interpretability and its attendant constraints mostly unnecessary. The imposing size, weight, power and cost of contemporary systems is problematic, and relief from factors that increase these metrics is important to the practicality of robotic systems. We present a system concept free from pixel basis sampling constraints that promotes efficient and adaptable sensing modes. The cornerstone of our approach is agile and arbitrary beam formation that, when combined with a generalized mathematical framework for imaging, is suited to the particular challenges and opportunities of robotic perception systems. Our hardware concept looks toward future systems with optical device technology closely resembling modern electronically-scanned-array radar that may be years away from practicality. We present the design concept and results from a prototype system constructed and tested in a laboratory environment using a combination of developed hardware and surrogate devices for beam formation. The technological status and prognosis for key components in the system is discussed.

  15. Laser induced x-ray `RADAR' particle physics model

    Science.gov (United States)

    Lockley, D.; Deas, R.; Moss, R.; Wilson, L. A.; Rusby, D.; Neely, D.

    2016-05-01

    The technique of high-power laser-induced plasma acceleration can be used to generate a variety of diverse effects including the emission of X-rays, electrons, neutrons, protons and radio-frequency radiation. A compact variable source of this nature could support a wide range of potential applications including single-sided through-barrier imaging, cargo and vehicle screening, infrastructure inspection, oncology and structural failure analysis. This paper presents a verified particle physics simulation which replicates recent results from experiments conducted at the Central Laser Facility at Rutherford Appleton Laboratory (RAL), Didcot, UK. The RAL experiment demonstrated the generation of backscattered X-rays from test objects via the bremsstrahlung of an incident electron beam, the electron beam itself being produced by Laser Wakefield Acceleration. A key initial objective of the computer simulation was to inform the experimental planning phase on the predicted magnitude of the backscattered X-rays likely from the test objects. This objective was achieved and the computer simulation was used to show the viability of the proposed concept (Laser-induced X-ray `RADAR'). At the more advanced stages of the experimental planning phase, the simulation was used to gain critical knowledge of where it would be technically feasible to locate key diagnostic equipment within the experiment. The experiment successfully demonstrated the concept of X-ray `RADAR' imaging, achieved by using the accurate timing information of the backscattered X-rays relative to the ultra-short laser pulse used to generate the electron beam. By using fast response X-ray detectors it was possible to derive range information for the test objects being scanned. An X-ray radar `image' (equivalent to a RADAR B-scan slice) was produced by combining individual X-ray temporal profiles collected at different points along a horizontal distance line scan. The same image formation process was used to generate

  16. Accurate extraction method for the FM response of tunable diode lasers based on wavelength modulation spectroscopy

    Science.gov (United States)

    Chen, J.; Hangauer, A.; Strzoda, R.; Amann, M.-C.

    2008-02-01

    An accurate wavelength modulation spectroscopy based method to measure the dynamics of the wavelength modulation behavior of tunable diode lasers is introduced in this paper. This method requires only standard equipment and a simple mechanical setup. Under the condition of a constant laser modulation current, the wavelength modulation amplitude can be determined by analysis of the distance between the two zero crossings of the measured second harmonic spectrum of gas absorption. When measuring at different modulation frequencies, the frequency response of the current-to-wavelength tuning coefficient can be obtained. The use of a frequency analyzer instead of a lock-in amplifier to obtain the second harmonic spectrum has two advantages: it provides a higher bandwidth and allows for very precise detection of the zero crossings because of the logarithmic output. The results exhibit very good agreement with a reference measurement performed with a fast FTIR Spectrometer.

  17. Bistatic (Multistatic) Radar Using Television or FM Broadcast%基于电视或调频广播的非合作式双(多)基地雷达及关键技术

    Institute of Scientific and Technical Information of China (English)

    曲长文; 何友

    2001-01-01

    基于电视或调频广播的非合作式双(多)基地雷达是以电视或调频广播的发射机作为非合作式双(多)基地雷达的辐射源,具有反侦察、抗干扰、反隐身、抗反辐射导弹的潜在优势,有良好的发展前景。介绍了基于电视或调频广播的非合作式双(多)基地雷达的发展历史和现状,分析了其基本原理及基本测量参量,探讨了一些实现基于电视或调频广播的非合作式双(多)基地雷达的关键技术。%Bistatic (multistatic) radar using television or FM broadcast is a kind of radar which employs a television or FM broadcast transmitter as the illuminator. Some advantages are obtained from this radar, such as anti-elint, electronic counter-countermeasure, detection of stealth targets and counter anti-radiation missile. This radar will be used in military area. The developing hisory and present situation of bistatic (multistatic) radar using television or FM broadcast is introduced in this paper. The principle of this radar is analysed and a receiver system block diagram is given. Basic measured parameters are time difference of arrival between the signal of a target and the signal from a transmitter, direction of arrival and Doppler frequency of a target. In addition, some key technologies for this radar are discussed. The synchronisation between transmitter and receiver in respect of antenna beams and time, the direction of arrival of a target, the signal processing in the receiver and the locating and tracking method for targets are included in the discussion.

  18. Radar and Laser Sensors for High Frequency Ocean Wave Measurement.

    Science.gov (United States)

    Kennedy, C. R.

    2016-02-01

    Experimental measurement of air-sea fluxes invariably take place using shipbourne instrumentation and simultaneous measurement of wave height and direction is desired. A number of researchers have shown that range measuring sensors combined with inertial motion compensation can be successful on board stationary or very slowly moving ships. In order to measure wave characteristics from ships moving at moderate to full speed the sensors are required to operate at higher frequency so as to overcome the Doppler shift caused by ship motion. This work presents results from some preliminary testing of laser, radar and ultrasonic range sensors in the laboratory and on board ship. The characteristics of the individual sensors are discussed and comparison of the wave spectra produced by each is presented.

  19. High Accuracy and Real-Time Gated Viewing Laser Radar

    Institute of Scientific and Technical Information of China (English)

    Dong Li; Hua-Jun Yang; Shan-Pei Zhou

    2011-01-01

    A gated viewing laser radar has an excellent performance in underwater low light level imaging,and it also provides a viable solution to inhibit backscattering.In this paper,a gated viewing imaging system according to the demand for real-time imaging is presented,and then the simulation is used to analyze the performance of the real-time gated viewing system.The range accuracy performance is limited by the slice number,the width of gate,the delay time step,the initial delay time,as well as the system noise and atmospheric turbulence.The simulation results indicate that the highest range accuracy can be achieved when the system works with the optimal parameters.Finally,how to choose the optimal parameters has been researched.

  20. Development of Coherent Laser Radar for Space Situational Awareness Applications

    Science.gov (United States)

    Prasad, N.; DiMarcantonio, A.

    2013-09-01

    NASA Langley Research Center (LaRC) is working on an innovative and high performance mobile coherent laser radar (ladar) system known as ExoSPEAR for space situational awareness applications in LEO and beyond. Based on continuously agile pulse doublet technology, the 100 W, nanosecond class, near-IR laser based coherent ladar is being developed for short dwell time measurements of resident space objects (RSOs). ExoSPEAR system is designed to provide rapid and precision tracking of RSOs over very long ranges. The goal is to demonstrate mm-class range resolution, mm/s class velocity resolution and microrad angular resolution with significantly reduced error-covariance in track accuracy. Precise orbit determination would help in advancing functionality of early warning systems for tracking uncooperative targets for planetary protection applications. Furthermore, improvements in resolution of micromotion measurements would enhance our understanding of astrodymanical properties of resident space objects. In this paper, salient features of the evolution and current experimental status of ExoSPEAR ladar architecture will be discussed. Performance simulations illustrating the dependence of range and velocity precision in LEO orbits on ladar power aperture product will be presented. Estimated limits on detectable optical cross sections of RSOs in LEO orbits will be analyzed.

  1. Spectral analysis, digital integration, and measurement of low backscatter in coherent laser radar

    Science.gov (United States)

    Vaughan, J. M.; Callan, R. D.; Bowdle, D. A.; Rothermel, J.

    1989-01-01

    A method of surface acoustic wave (SAW) spectral analysis and digital integration that has been used previously in coherent CW laser work with CO2 lasers at 10.6 microns is described. Expressions are derived for the signal to noise ratio in the measured voltage spectrum with an approximation for the general case and rigorous treatment for the low signal case. The atmospheric backscatter data accumulated by the airborne LATAS (laser true airspeed) coherent laser radar system are analyzed.

  2. Research and development cooperation project on environmental measurement using laser radar in fiscal 1994; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The paper outlined activities in fiscal 1994 in the R and D cooperation project on a laser radar for environmental measurement. In the activities in fiscal 1994 of `the ODA laser radar development committee,` the committee held four meetings, two field surveys were carried out, and two researchers were invited from Indonesia. In the field survey, the environment in Jakarta city was investigated in terms of changes in population and number of the cars registered. Further, from data collected during 1994-1998 in the central Jakarta city, the following were made clear: the trend of a decrease in SO2, the trend of a rapid increase and an excess of NO2 content over the environmental standard, the status of pollution of which the level is close to the upper limit of the environmental standard of dust, etc. In the meeting of the policy study for the field survey at LIPI headquarters, Japan proposed a system which is constituted of a difference absorption laser radar, two Mie scattering laser radars, and a central processing unit. The sites proposed were studied in cooperation with Indonesia. 40 refs., 65 figs., 9 tabs.

  3. Research cooperation of the development of laser radar for environmental measurements; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Research and development of the laser radar for measuring the air pollution in urban areas and the environmental information network have been conducted through the cooperation with Indonesian researchers. A measurement system suitable to actual situation of Indonesia has been constructed. In FY 1996, some works have been conducted as in the final fiscal year. To set the laser radar for environmental measurements and to make a plan of measurement research, conditions of air pollution in Indonesia and setting places of systems have been investigated. Opinions for the cooperation research have been exchanged with Indonesian researchers. Actual trends of the environmental measurements technology using laser radar have been surveyed. Indonesian researchers have been invited to learn operation and data processing of the system. One unit of MIE diffusion laser radar system has been designed and fabricated, and an additional data processing program has been made. The system has been delivered to Jakarta and installed. After the adjustment, performance tests have been conducted to complete the construction of the system. 3 refs., 72 figs., 10 tabs.

  4. The use of phase modulation optimization for power lasers. Minimizing the FM-AM conversion while preserving spectral broadening functionalities required for fusion; Optimisation de la modulation de phase utilisee pour les lasers de puissance. Minimisation de la conversion FM-AM tout en conservant les fonctionnalites d'elargissement spectral necessaires a la fusion

    Energy Technology Data Exchange (ETDEWEB)

    Hocquet, St

    2009-11-15

    This research thesis deals with the problem of phase modulations in power lasers (such as the MegaJoule laser which is developed in France) and their impact of different physical phenomena like the suppression of the stimulated Brillouin scattering (which is necessary to avoid optics damage) and the optical smoothing which allows a spatial homogenisation of focal stains. The author deeply discusses the phase modulation counterparts, and more particularly the FM-AM conversion which is the source of unwanted intensity modulation and of energy loss. He reports the development of a comprehensive modelling of phenomena generating FM-AM conversion on a power laser chain. He theoretically and experimentally studies two methods allowing the FM-AM conversion to be reduced to a given spectral distortion: the compensation of transfer functions and the modification of the phase modulation signal to make it less sensitive to spectral distortion effects. For this last method, he determines the ideal spectrum shape for the phase modulation, and proposes a method to approach it. He shows the feasibility of such a method and reports experiments showing to which extent these solutions may improve performance of power lasers. Finally, he proposed optimised solutions for the MegaJoule Laser.

  5. Integrating radar and laser-based remote sensing techniques for monitoring structural deformation of archaeological monuments

    OpenAIRE

    Tapete D.; Casagli N.; Luzi G.; Fanti R.; Gigli G.; Leva D.

    2013-01-01

    Ground-Based Synthetic Aperture Radar Interferometry (GBInSAR) and Terrestrial Laser Scanning (TLS) were purposely integrated to obtain 3D interferometric radar point clouds to facilitate the spatial interpretation of displacements affecting archaeological monuments. The paper describes the procedure to implement this integrated approach in the real-world situations of surveillance of archaeological and built heritage. Targeted tests were carried out on the case study of the Domus Tiberiana s...

  6. Terahertz inverse synthetic aperture radar imaging using self-mixing interferometry with a quantum cascade laser.

    Science.gov (United States)

    Lui, H S; Taimre, T; Bertling, K; Lim, Y L; Dean, P; Khanna, S P; Lachab, M; Valavanis, A; Indjin, D; Linfield, E H; Davies, A G; Rakić, A D

    2014-05-01

    We propose a terahertz (THz)-frequency synthetic aperture radar imaging technique based on self-mixing (SM) interferometry, using a quantum cascade laser. A signal processing method is employed which extracts and exploits the radar-related information contained in the SM signals, enabling the creation of THz images with improved spatial resolution. We demonstrate this by imaging a standard resolution test target, achieving resolution beyond the diffraction limit.

  7. High-frequency scannerless imaging laser radar for industrial inspection and measurement applications

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, R.L.; Williams, R.J.; Matthews, J.D.

    1996-11-01

    This report describes the development and testing of a high-frequency scannerless imaging laser radar system to evaluate its viability as an industrial inspection and measurement sensor. We modified an existing 5.5-Mhz scannerless laser radar to operate at 150 Mhz, and measured its performance including its spatial resolution and range resolution. We also developed new algorithms that allow rapid data reduction with improved range resolution. The resulting 150-Mhz ladar system demonstrated a range resolution of better than 3 mm, which represents nearly a factor-of-100 improvement in range resolution over the existing scannerless laser radar system. Based on this work, we believe that a scannerless range imager with 1- to 2-mm range resolution is feasible. This work was performed as part of a small-business CRADA between Sandia National Laboratories and Perceptron, Inc.

  8. Research cooperation in the development of laser radar for environmental measurements. Environmental network; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku. Kankyo network

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Among the research cooperation in the development of laser radar for environmental measurements with Indonesia between FY 1993 and FY 1996, results of the research and development of the environmental network are summarized. For the environmental information network, the Tokyo NOC is linked as an Internet connection point in Japan with the Jakarta NOC using an international dedicated line with a capacity of 64 Kbps. The Tokyo NOC is linked with domestic environmental information researchers using Internet. Thus, data stored in the data processing system of laser radar can be exchanged, information in both countries can be exchanged using E-mail, and data can be accumulated. For the research cooperation with Indonesia, research of path control and information relay server, research of effective transmission of data on the network, and research of multimedia communication have been conducted. The multimedia communication, distributed processing, and extension of dedicated line network using PPTP have been also conducted. 39 figs., 4 tabs.

  9. Active laser radar (lidar) for measurement of corresponding height and reflectance images

    Science.gov (United States)

    Froehlich, Christoph; Mettenleiter, M.; Haertl, F.

    1997-08-01

    For the survey and inspection of environmental objects, a non-tactile, robust and precise imaging of height and depth is the basis sensor technology. For visual inspection,surface classification, and documentation purposes, however, additional information concerning reflectance of measured objects is necessary. High-speed acquisition of both geometric and visual information is achieved by means of an active laser radar, supporting consistent 3D height and 2D reflectance images. The laser radar is an optical-wavelength system, and is comparable to devices built by ERIM, Odetics, and Perceptron, measuring the range between sensor and target surfaces as well as the reflectance of the target surface, which corresponds to the magnitude of the back scattered laser energy. In contrast to these range sensing devices, the laser radar under consideration is designed for high speed and precise operation in both indoor and outdoor environments, emitting a minimum of near-IR laser energy. It integrates a laser range measurement system and a mechanical deflection system for 3D environmental measurements. This paper reports on design details of the laser radar for surface inspection tasks. It outlines the performance requirements and introduces the measurement principle. The hardware design, including the main modules, such as the laser head, the high frequency unit, the laser beam deflection system, and the digital signal processing unit are discussed.the signal processing unit consists of dedicated signal processors for real-time sensor data preprocessing as well as a sensor computer for high-level image analysis and feature extraction. The paper focuses on performance data of the system, including noise, drift over time, precision, and accuracy with measurements. It discuses the influences of ambient light, surface material of the target, and ambient temperature for range accuracy and range precision. Furthermore, experimental results from inspection of buildings, monuments

  10. Gated viewing and high-accuracy three-dimensional laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a fast and high-accuracy three-dimensional (3-D) imaging laser radar that can achieve better than 1 mm range accuracy for half a million pixels in less than 1 s. Our technique is based on range-gating segmentation. We combine the advantages of gated viewing with our new fast...

  11. Gated viewing and high-accuracy three-dimensional laser radar

    DEFF Research Database (Denmark)

    Busck, Jens; Heiselberg, Henning

    2004-01-01

    We have developed a fast and high-accuracy three-dimensional (3-D) imaging laser radar that can achieve better than 1 mm range accuracy for half a million pixels in less than 1 s. Our technique is based on range-gating segmentation. We combine the advantages of gated viewing with our new fast...

  12. Time analysis and processing of FM-CW signals

    NARCIS (Netherlands)

    Meta, A.; Hoogeboom, P.

    2003-01-01

    Combining frequency modulated continuous wave (FM-CW) teehnology with synthetic aperture radar (SAR) methods leads to a cost-effective, high resolution imaging radar for smallscale applications. There is a growing interest in miniaturized versions of such sysfems. The radar delivers its output in th

  13. Airborne FM-CW SAR and Integrated Navigation System Data Fusion

    NARCIS (Netherlands)

    Lorga, J.F.M.; Meta, A.; Wit, J.J.M. de; Mulder, J.A.

    2005-01-01

    The combination of compact FM-CW radar technology and high resolution SAR pro- cessing techniques should pave the way for the development of a small and cost e®ective imaging radar with high resolution. However, airborne SAR is a very novel application for FM-CW radars. In order to investigate the p

  14. Investigation of laser radar systems based on mid-infrared semiconductor lasers

    Science.gov (United States)

    Rybaltowski, Adam

    This dissertation deals with the possibility of utilizing mid-infrared semiconductor lasers in systems of optical remote sensing with range resolution, called laser radar or lidar. The main subject investigated in this dissertation is two-fold: firstly, an analysis of the signal-to-noise ratio (SNR) and related maximum sensing range calculations in this type of lidar based on available system components, and---secondly---improvements in the Random-Modulation Continuous-Wave (RM-CW) lidar technique to better utilize available mid-infrared semiconductor lasers. As far as the SNR analysis is concerned, an appropriate framework has been constructed to analyze post-demodulation noise in mid-infrared direct-detection RM-CW lidar. It is based on a generalization of the Wiener-Khintchine theorem; noise is assumed to be additive, stationary, and have an arbitrary power spectrum. This is in contrast to the SNR analysis in the literature on this subject, which is inadequate for mid-infrared RM-CW lidar as it only considers Poissonian fluctuations of the number of detected photons. In addition to regular SNR analysis, the framework derived in this dissertation allows treatment of singularities such as demodulation with an unbalanced sequence in 1/f noise. To calculate maximum lidar sensing range, the following detection limits have been considered: signal shot noise, background blackbody radiation shot noise based on the Background-Limited Photodetection (BLIP) detectivity limit, and minimum-size detector noise given by diffraction-limited focusing. The latter is found to be of greatest practical interest. Furthermore, a lidar figure of merit has been introduced, and all quantities related to lidar performance and its detection limits have been presented graphically. Since pseudo-random sequences discussed in the literature have been found highly non-optimal for most applications of RM-CW lidar, a framework for the construction of new pseudo-random sequences of desired

  15. Synthetic-aperture imaging laser radar: laboratory demonstration and signal processing.

    Science.gov (United States)

    Beck, Steven M; Buck, Joseph R; Buell, Walter F; Dickinson, Richard P; Kozlowski, David A; Marechal, Nicholas J; Wright, Timothy J

    2005-12-10

    The spatial resolution of a conventional imaging laser radar system is constrained by the diffraction limit of the telescope's aperture. We investigate a technique known as synthetic-aperture imaging laser radar (SAIL), which employs aperture synthesis with coherent laser radar to overcome the diffraction limit and achieve fine-resolution, long-range, two-dimensional imaging with modest aperture diameters. We detail our laboratory-scale SAIL testbed, digital signal-processing techniques, and image results. In particular, we report what we believe to be the first optical synthetic-aperture image of a fixed, diffusely scattering target with a moving aperture. A number of fine-resolution, well-focused SAIL images are shown, including both retroreflecting and diffuse scattering targets, with a comparison of resolution between real-aperture imaging and synthetic-aperture imaging. A general digital signal-processing solution to the laser waveform instability problem is described and demonstrated, involving both new algorithms and hardware elements. These algorithms are primarily data driven, without a priori knowledge of waveform and sensor position, representing a crucial step in developing a robust imaging system.

  16. Noise Temperature Characteristics and Gain-control of Avalanche Photodiodes for Laser Radar

    Institute of Scientific and Technical Information of China (English)

    CAI Xi-ping; SHANG Hong-Bo; BAI Ji-yuan; YANG Shuang; WANG Li-na

    2008-01-01

    Avalanche photodiodes(APDs) are promising light sensors with high quantum efficiency and low noise. It has been extensively used in radiation detection, laser radar and other weak signal detection fields. Unlike other photodiodes, APD is a very sensitive light detector with very high internal gain. The basic theory shows that the gain of APD is related to the temperature. The internal gain fluctuates with the variation of temperature. Investigated was the influence of the variation of the gain induced by the fluctuation of temperature on the output from APD for a very weak laser pulse input in laser radar. An active reverse-biased voltage compensation method is used to stabilize the gain of APD. An APD model is setup to simulate the detection of light pulse signal. The avalanche process, various noises and temperature's effect are all included in the model. Our results show that for the detection of weak light signal such as in laser radar, even a very small fluctuation of temperature could cause a great effect on APD's gain. The results show that the signal-to-noise ratio of the APD's output could be improved effectively with the active gain-control system.

  17. A high detection probability method for Gm-APD photon counting laser radar

    Science.gov (United States)

    Zhang, Zi-jing; Zhao, Yuan; Zhang, Yong; Wu, Long; Su, Jian-zhong

    2013-08-01

    Since Geiger mode Avalanche Photodiode (GmAPD) device was applied in laser radar system, the performance of system has been enhanced due to the ultra-high sensitivity of GmAPD, even responding a single photon. However, the background noise makes ultra-high sensitive GmAPD produce false alarms, which severely impacts on the detection of laser radar system based on Gm-APD and becomes an urgent problem which needs to be solved. To address this problem, a few times accumulated two-GmAPDs strategy is proposed in this paper. Finally, an experimental measurement is made under the background noise in sunny day. The results show a few times accumulated two- GmAPDs strategy can improve the detection probability and reduce the false alarm probability, and obtain a clear 3D image of target.

  18. Advanced system model for 1574-nm imaging, scannerless, eye-safe laser radar

    Science.gov (United States)

    Schael, Ulrich; Rothe, Hendrik

    2002-10-01

    Laser radar based on gated viewing uses narrow laser pulses to illuminate a whole scene for direct (incoherent) detection. Due to the time of flight principle and a very fast shutter with precisely controlled delay time, only light reflected in the range R (range slice ΔR) is detected by a camera. Scattered light which reaches the shutter outside a given exposure time (gate) is suppressed. Hence, it is possible to "look" along the optical axis through changing atmospheric transmissions (rain, haze, fog, snow). For each laser pulse, the grey value image ES(x,y) of the camera is captured by a framegrabber for subsequent evaluation. Image sequences from these laser radar systems are ideally suited to recognize objects, because of the automatic contrast generation of the technology. Difficult object recognition problems, detection, target tracking, or obstacle avoidance at bad weather conditions are favorite applications. In this paper we discuss improvements in the system modelling and simulation of our laser radar system. Formerly the system performance was calculated for the whole system using the signal-to-noise ratio (SNR), leading to a general estimation of the maximum range of target detection. Changing to a pixel oriented approach, we are now able to study the system response for targets with arbitrary two and even three dimensional form. We take into account different kinds of target reflectivity and the Gaussian nature of the illuminating laser spot. Hence it is possible to simulate gray value images (range slices) and calculate range images. This will lead to a modulation transfer function for the system in future. Finally, the theoretical considerations are compared with experimental results from indoor measurements.

  19. Research and development cooperation project on environmental measurement using laser radar in fiscal 1993; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    As one of the international research cooperation projects, the research cooperation in developing laser radar for environment measurement started between Japan and Indonesia. The project is scheduled to be carried out in a 4-year plan starting fiscal 1993. In fiscal 1993, conducted were negotiations with Indonesia on its implementation and a field survey. Between January 6 and 15, 1994, the first field survey was made in terms of topography, climate, road network and traffic situation of Jakarta city, and the proposed sites for installation were reported. The paper also introduced the reception system on the Indonesian side and a request for technical learning through stay in Japan. The second field survey was conducted between February 27 and March 6, 1994. Indonesia requested that they want to make laser radar observation not only for the local area, but the one that covers industrial areas, central urban areas and residential areas. Incidentally, there was an opinion that it is important to elucidate the pollution mechanism. 19 refs., 43 figs., 6 tabs.

  20. Maximum detection range limitation of pulse laser radar with Geiger-mode avalanche photodiode array

    Science.gov (United States)

    Luo, Hanjun; Xu, Benlian; Xu, Huigang; Chen, Jingbo; Fu, Yadan

    2015-05-01

    When designing and evaluating the performance of laser radar system, maximum detection range achievable is an essential parameter. The purpose of this paper is to propose a theoretical model of maximum detection range for simulating the Geiger-mode laser radar's ranging performance. Based on the laser radar equation and the requirement of the minimum acceptable detection probability, and assuming the primary electrons triggered by the echo photons obey Poisson statistics, the maximum range theoretical model is established. By using the system design parameters, the influence of five main factors, namely emitted pulse energy, noise, echo position, atmospheric attenuation coefficient, and target reflectivity on the maximum detection range are investigated. The results show that stronger emitted pulse energy, lower noise level, more front echo position in the range gate, higher atmospheric attenuation coefficient, and higher target reflectivity can result in greater maximum detection range. It is also shown that it's important to select the minimum acceptable detection probability, which is equivalent to the system signal-to-noise ratio for producing greater maximum detection range and lower false-alarm probability.

  1. Detection probabilities for photon-counting avalanche photodiodes applied to a laser radar system.

    Science.gov (United States)

    Henriksson, Markus

    2005-08-20

    Arrays of photon-counting avalanche photodiodes with time-resolved readout can improve the performance of three-dimensional laser radars. A comparison of the detection and false-alarm probabilities for detectors in linear mode and in Geiger mode is shown. With low background radiation their performance is comparable. It is shown that in both cases it will be necessary to process several laser shots of the same scene to improve detection and reduce the false-alarm rate. Additional calculations show that the linear mode detector is much better at detecting targets behind semitransparent obscurations such as vegetation and camouflage nets.

  2. Study of imaging radar using ultra-wideband microwave-modulated infrared laser

    Science.gov (United States)

    Mase, Atsushi; Kogi, Yuichiro; Ikezi, Hiroyuki; Inutake, Masaaki; Wang, Xiaolong

    2016-09-01

    In this paper, we present an ultra-wideband microwave-modulated laser radar which is designed and fabricated for improvement of the spatial resolution both in the range direction and the azimuth direction. The amplitude modulation in a range of 0.01-18 GHz is applied to an infrared laser source of 1550 nm wavelength. The frequency and the bandwidth are assigned by the Administration of Radio under the Ministry of Internal Affairs and Communications in Japan. However, there is no bandwidth limitation in the infrared region. Considering the influence of radiation pattern for microwave antennas case, there is no side lobe in laser beam transmission. Ambiguous signal and interferences which are returned from the ground can be suppressed. A prototype of laser-radar system with a fiber collimator for both transmitting and receiving optics has been fabricated. A vector network analyzer is used to obtain S21 signal between the microwave modulation input and that of received signal. The system is, at first, applied to the measurement of the distance (position) of an object. It is proved that the spatial resolution is less than 1 cm during 5-10 m. As an initial experiment, we have succeeded to obtain 3D image of object by scanning a laser beam in two dimensions.

  3. Pseudo-random noise-continuous-wave laser radar for surface and cloud measurements

    Science.gov (United States)

    Matthey, Renaud; Mitev, Valentin

    2005-03-01

    Laser radar (lidar) application may require an instrument with compact size, long life of the components, low consumption and eye-safety. One possibility to achieve these features is to use a continuous-wave (cw) diode laser as lidar transmitter. A practical way to perform range-resolved measurements with a cw laser diode is the pseudo-random noise (PRN) modulation. This paper presents a compact PRN-cw lidar, using a 370-mW cw diode laser and an APD as detector. Daytime measurements of cloud base and topographic surface are demonstrated with the PRN-cw lidar technique, where the range detection exceeds 2 km. The detection of the topographic surface is performed with integration time of some tens of milliseconds during daytime and some tens of microseconds during night-time.

  4. Comparing helicopter-borne profiling radar with airborne laser scanner data for forest structure estimation.

    Science.gov (United States)

    Piermattei, Livia; Hollaus, Markus; Pfeifer, Norbert; Chen, Yuwei; Karjalainen, Mika; Hakala, Teemu; Hyyppä, Juha; Wagner, Wolfgang

    2017-04-01

    Forests are complex ecosystems that show substantial variation with respect to climate, management regime, stand history, disturbance, and needs of local communities. The dynamic processes of growth and disturbance are reflected in the structural components of forests that include the canopy vertical structure and geometry (e.g. size, height, and form), tree position and species diversity. Current remote-sensing systems to measure forest structural attributes include passive optical sensors and active sensors. The technological capabilities of active remote sensing like the ability to penetrate the vegetation and provide information about its vertical structure has promoted an extensive use of LiDAR (Light Detection And Ranging) and radar (RAdio Detection And Ranging) system over the last 20 years. LiDAR measurements from aircraft (airborne laser scanning, ALS) currently represents the primary data source for three-dimensional information on forest vertical structure. Contrary, despite the potential of radar remote sensing, their use is not yet established in forest monitoring. In order to better understand the interaction of pulsed radar with the forest canopy, and to increase the feasibility of this system, the Finnish Geospatial Research Institute has developed a helicopter-borne profiling radar system, called TomoRadar. TomoRadar is capable of recording a canopy-penetrating profile of forests. To georeference the radar measurements the system was equipped with a global navigation satellite system and an inertial measurement unit with a centimeter level accuracy of the flight trajectory. The TomoRadar operates at Ku-band, (wave lengths λ 1.5cm) with two separated parabolic antennas providing co- and cross-polarization modes. The purpose of this work is to investigate the capability of the TomoRadar system, for estimating the forest vertical profile, terrain topography and tree height. We analysed 600 m TomoRadar crosspolarized (i.e. horizontal - vertical

  5. Application of phase retrieval algorithm in reflective tomography laser radar imaging

    Institute of Scientific and Technical Information of China (English)

    Xiaofeng Jin; Jianfeng Sun; Yi Yan; Yu Zhou; Liren Liu

    2011-01-01

    @@ We apply phase retrieval method to align projection data for tomographic reconstruction in reflective tomography laser radar imaging. In our experiment, the target is placed on a spin table with an unknown,but fixed, axis. The oscillatory motion of the target in the incident direction of the laser pulse is added at each view to simulate the real satellites random motion. The experimental simulation results demonstrate the effectiveness of this method to improve image reconstruction quality. Future research also includes the development of projection registration based on phase retrieval for targets with more complicated structure.%We apply phase retrieval method to align projection data for tomographic reconstruction in reflective tomography laser radar imaging. In our experiment, the target is placed on a spin table with an unknown,but fixed, axis. The oscillatory motion of the target in the incident direction of the laser pulse is added at each view to simulate the real satellites random motion. The experimental simulation results demonstrate the effectiveness of this method to improve image reconstruction quality. Future research also includes the development of projection registration based on phase retrieval for targets with more complicated structure.

  6. Classification of Ground Objects Using Laser Radar Data

    OpenAIRE

    Brandin, Martin; Hamrén, Roger

    2003-01-01

    Accurate 3D models of natural environments are important for many modelling and simulation applications, for both civilian and military purposes. When building 3D models from high resolution data acquired by an airborne laser scanner it is de-sirable to separate and classify the data to be able to process it further. For example, to build a polygon model of a building the samples belonging to the building must be found. In this thesis we have developed, implemented (in IDL and ENVI), and eval...

  7. Design and Tests of A Cable Detection Laser Imaging Radar System

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-ran; YUAN Jin

    2005-01-01

    Rotorcraft in low-level flight is endangered by power lines or telephone wires. The development of automation tools that can detect obstacles in the flight path and warn the crew would significantly reduce pilot workload and increase safety. Therefore, a cable detection radar system is developed. The real-time dynamic imaging synchronizing with radar space scanning has been implemented in developed ladar system. The requirements of the flight mission to prevent "wire strike"are analyzed and estimated, the advantages and disadvantages of the millimeter wave system with the laser system are weighted. The result shows that Laser system is the best suited for helicopter avoidance obstacle. In addition, several design gist of detecting wire radar that was used in the developed ladar system is proposed and the developed zero backlash imaging technology and several advanced warning function are described. The detailed results of system ground tests and the performances description are presented. The ground test of the developed ladar system has demonstrated that the developed imaging ladar system performance can achieve and satisfy the requirements of the mission to prevent "wire strike".

  8. TDLAS中激光器IM/FM相位延迟实时测量方法研究%IM/FM Phase Delay Time Measurement Method of Laser for TDLAS

    Institute of Scientific and Technical Information of China (English)

    张超; 马维光

    2014-01-01

    The present paper presents an method of using fiber Michelson interferometer to measure the Intensity-frequency (IM/FM ) phase delay change of the laser ,it could realize the phase delay time measurement ,while modulating the laser .Experimen-tal results show that the laser output signal intensity-frequency (IM/FM ) phase delay of the laser has some differences from the theoretical value .The proposed method can be used to compensate for real-time signal strength-frequency (IM/FM ) phase delay effect on the gas concentration measurement results .%在基于谐波检测法的TDLAS(可调谐二极管激光吸收光谱)系统中,在通过改变激光器注入电流实现激光频率扫描和调制的同时引起激光强度的变化,激光器输出信号的强度-频率(IM/FM )相位延迟φm 的变化将直接导致谐波系数波动,带来系统误差。提出一种利用光纤迈克尔逊干涉仪实现激光器输出信号强度-频率(IM/FM )相位延迟φm 的测量方法,能在激光器调制测量的同时实时测量相位延迟φm 。实验结果表明,激光器输出信号强度-频率(IM/FM )相位延迟φm 与理论值π有一定差异。研究提出的方法可以用来实时补偿信号强度-频率(IM/FM )相位延迟φm 对气体浓度测量结果的影响。

  9. An operational theory of laser-radar selenodesy

    Science.gov (United States)

    Wildey, R.L.; Schlier, R.E.; Hull, J.A.; Larson, G.

    1967-01-01

    A theory of the utilization of laser techniques for ranging from the Earth to the Moon for the purpose of providing control points on the lunar surface at which the figure of the Moon is measured to an accuracy at least an order of magnitude better than that of the present astrometric measurements is presented. This, in turn, increases the accuracy of the horizontal selenocentric coordinates of topographical features measured by present astrometric methods. The improvement in the vertical and horizontal coordinates of control points in the Apollo landing zone will aid in the analysis of Unmanned Lunar Orbiter photographs for the selection of Apollo landing sites. The present discussion proposes the means of obtaining the ground control upon which the Orbiter photogrammetry is to be fastened. In addition, a technique of combining Goldstone tracking data to show where the resulting lunar figure is positioned relative to the Moon's center of mass is presented. If corner reflectors are placed on the lunar surface, as suggested by many members of the scientific community, or on a lunar orbiting vehicle, one or more Earth-based laser ranging systems are essential. These reflectors will give enough enhancement in return signal to allow for an additional increase in range accuracy of one to two orders of magnitude. In addition to the primary data on the figure of the Moon, a number of other measurements of scientific importance are then readily obtainable. As far as the measurement of control points is concerned, however, the use of corner reflectors is not essential for the success of this project. Questions regarding the influence on the present shape of the Moon of the frozen tide, isostasy, and past impacts of large asteroids appear in large part answerable through the data which are indicated to be obtainable under the present theory. ?? 1967.

  10. Multihit mode direct-detection laser radar system using a Geiger-mode avalanche photodiode.

    Science.gov (United States)

    Oh, Min Seok; Kong, Hong Jin; Kim, Tae Hoon; Hong, Keun Ho; Kim, Byung Wook; Park, Dong Jo

    2010-03-01

    In this paper, a direct-detection laser radar system that uses a Geiger-mode avalanche photodiode (GAPD) of relatively short dead time (45 ns) is described. A passively Q-switched microchip laser is used as a laser source and a compact peripheral component interconnect system, which includes a time-to-digital converter (TDC), is set up for fast signal processing. With both the GAPD and the TDC functioning multistop acquisition, the system operates in a multihit mode. The software for the three-dimensional visualization and an algorithm for the removal of noise are developed. It is shown that the single-shot precision of the system is approximately 10 cm (sigma) and the precision is improved by increasing the number of laser pulses to be averaged so that the precision of approximately 1 cm (sigma) was acquired with more than 150 laser pulses scattered from the target. The accuracy of the system is measured to be 12 cm when the energy of the emitted laser pulse varies with a factor of 7.

  11. Intelligent multisensor concept for image-guided 3D object measurement with scanning laser radar

    Science.gov (United States)

    Weber, Juergen

    1995-08-01

    This paper presents an intelligent multisensor concept for measuring 3D objects using an image guided laser radar scanner. The field of application are all kinds of industrial inspection and surveillance tasks where it is necessary to detect, measure and recognize 3D objects in distances up to 10 m with high flexibility. Such applications might be the surveillance of security areas or container storages as well as navigation and collision avoidance of autonomous guided vehicles. The multisensor system consists of a standard CCD matrix camera and a 1D laser radar ranger which is mounted to a 2D mirror scanner. With this sensor combination it is possible to acquire gray scale intensity data as well as absolute 3D information. To improve the system performance and flexibility, the intensity data of the scene captured by the camera can be used to focus the measurement of the 3D sensor to relevant areas. The camera guidance of the laser scanner is useful because the acquisition of spatial information is relatively slow compared to the image sensor's ability to snap an image frame in 40 ms. Relevant areas in a scene are located by detecting edges of objects utilizing various image processing algorithms. The complete sensor system is controlled by three microprocessors carrying out the 3D data acquisition, the image processing tasks and the multisensor integration. The paper deals with the details of the multisensor concept. It describes the process of sensor guidance and 3D measurement and presents some practical results of our research.

  12. Single-frequency mid-infrared optical parametric oscillator source for coherent laser radar.

    Science.gov (United States)

    Hanson, F; Poirier, P; Arbore, M A

    2001-11-15

    We report on the design and characterization of a highly coherent mid-IR source at 3.57mum based on a single-frequency optical parametric oscillator. Detailed frequency and amplitude noise spectra have been measured. The rms intensity noise from 1.2 to 1000 Hz was 0.03%, and a rms frequency drift of 8 kHz in 1 ms was observed. We have also demonstrated the utility of this source for coherent laser radar applications by measuring micro-Doppler spectra from vibrating targets.

  13. Two Decades of Elevation Changes of the Greenland Ice Sheet from Radar and Laser Altimetry.

    Science.gov (United States)

    Sandberg Sorensen, L.; Forsberg, R.; Khvorostovsky, K.; Meister, R.; Simonsen, S. B.

    2015-12-01

    The Greenland Ice Sheet has been mapped by radar altimetry since the launch of ERS-1 in 1991, which was followed by ERS-2, Envisat and currently CryoSat-2. For the period 2003-2009 the ice sheet topography was also mapped by laser altimetry by the ICESat mission. Here, we apply suitable elevation change algorithms to radar data from ERS-1, ERS-2, Envisat, and CryoSat-2 data, with the goal to derive continuous, ice sheet-wide elevation changes for the period 1992 to 2015. This analysis has been made possible through the recent release of data from the REAPER project, in which ERS-1 and ERS-2 radar have been reprocessed in a consistent way to that used for Envisat data. Over this 23-year period, the pattern of elevation changes varies significantly. Whilst thickening and thinning can both be observed during different periods, the overall trend of the elevation of the ice sheet is negative, i.e. an overall lowering can be seen during the two decades studied. This work is part of the ESA Greenland Ice Sheet CCI project. We compare elevation changes derived from radar and laser altimetry (2003-09) and find a complex pattern of difference between the two sensor types, and we explain how some of this pattern can be explained by changes in firn compaction and accumulation rates, obtained from a regional climate model and an offline firn model. Also we show how this pattern changes if using differently retracked Envisat data. A special focus will be on results obtained from the CryoSat-2 measurements that provide radar heights of unprecedented coverage and resolution. Here we present the results of a validation exercise carried out as part of the ESA-funded CryoVAL-LI project in which the accuracy of the CryoSat-2 measurements of land ice is assessed. The results presented here signify an important milestone in measuring the surface elevation of the ice sheet: providing us with an insight into past as well as recent changes, providing up-to-date information on the behaviour

  14. The accuracy of satellite radar altimeter data over the Greenland ice sheet determined from airborne laser data

    DEFF Research Database (Denmark)

    Bamber, J.L.; Ekholm, Simon; Krabill, W.

    1998-01-01

    The 336 days of the geodetic phase of ERS-1 provides dense coverage, by satellite radar altimetry, of the whole of the Greenland ice sheet. These data have been used to produce a digital elevation model of the ice sheet. The errors present in the altimeter data were investigated via a comparison...... with airborne laser altimeter data an absolute accuracy typically in the range 2-10 cm +/- 10 cm. Comparison of differences between the radar and laser derived elevations, showed a correlation with surface slope. The difference between the two data sets ranged from 84 cm +/- 79 cm for slopes below 0.1 degrees...

  15. Integrated multi-channel receiver for a pulsed time-of-flight laser radar

    Science.gov (United States)

    Jiang, Yan; Liu, Ruqing; Zhu, Jingguo

    2015-04-01

    An integrated multi-channel receiver for a pulsed time-of-flight (TOF) laser rangefinder has been designed in this paper. The receiver chip as an important component of the laser radar device has been implemented in a 0.18um CMOS process. It consists of sixteen channels and every channel includes preamplifier, amplifier stages, high-pass filter and a timing discriminator which contains a timing comparator and a noise comparator. Each signal paths is independent of other channels. Based on the simulations, the bandwidth and transimpedance of the amplifier channel are 652MHz, 99dBΩ. Under the simulation condition of TT corner and 27°C, the propagation delay of the discriminator is 2.15ns and the propagation delay dispersion is 223ps. The power consumption during continuous measurement is 810mW, and the operating temperature range of the device is -10~60°C.

  16. Analysis of influential factors on a space target's laser radar cross-section

    Science.gov (United States)

    Han, Yi; Sun, Huayan; Guo, Huichao

    2014-03-01

    This paper utilises the idea of theoretical analysis to introduce a fast and visual laser radar cross-section (LRCS) calculation method for space targets that is implemented with OpenGL. We chose the cube, cylinder and cone as targets based on the general characteristics of satellite shapes. The four-parameter mono-station BRDF is used, and we assume the surface materials are either purely diffuse, purely specular or mixed. The degree of influence on a target's total LRCS of the target's shape and size and the surface materials' BRDF are described. We describe the general laws governing influential factors by comparing simulated results. These conclusions can provide a reference for new research directions and methods to determine a target's laser scattering characteristics.

  17. Research and development cooperation project on environmental measurement using laser radar in fiscal 1995 (environmental network); Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku (kankyo network)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    As a part of the cooperative work with Indonesia of R and D of a laser radar for environmental measurement, the paper described the development of an environmental network. The field survey was conducted in April, July and December 1995 and in March 1996. For the investigational research, five meetings of the committee and four times of group work were held. The Asian environmental network was studied in terms of its arrangement, operation and management, and the overall network/path control design were being prepared. To make the persons concerned abroad and in Japan understood the APEC Osaka Conference held in November 1995, a homepage APEC `95 Kansai was opened using WWW (World Wide Web, a decentralized hyper media system which can dispatch information to the whole world by network using hyper text). Moreover, in connection with this, a homepage was opened of CICC (Center of the International Cooperation for Computerization, a center controlling the whole Asian environmental information network system where E-mail and data are exchangeable with Indonesia via Tokyo NOC (Network Operation Center)). 49 figs., 8 tabs.

  18. Research and development cooperation project on environmental measurement using laser radar (environmental network) in fiscal 1993; Kankyo keisokuyo laser radar no kaihatsu ni kansuru kenkyu kyoryoku (kankyo network)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-03-01

    For the purpose of contributing to the research cooperation project on the development of a laser radar for environmental measurement, the paper surveyed the present and future trend of the environment related information network in Indonesia. The survey was conducted in terms of a name of the network, the main administration body, the number of users, the utilization status, the use protocol, details of service, domestic mode installation sites and the main administration body, accounting system, types of the network used, reliability and stability of network, limitations on the use and details of the limitation, etc. The plan for expanding telecommunication equipment is being advanced in a very quick tempo. However, there are many problems in digitalization, and it is feared that the plan will be delayed. As to telecommunication quality and connection quality, the telecommunication completion rate, SCR, is very low, approximately 24% on average, which is equal to that around 1990 in Japan. The business service for users is all bureaucratic since they have a lot of applications for the installation piling up with no exception to the rule of developing countries. 23 figs., 10 tabs.

  19. Comparison of space borne radar altimetry and airborne laser altimetry over sea ice in the Fram Strait

    DEFF Research Database (Denmark)

    Giles, K.A.; Hvidegaard, Sine Munk

    2006-01-01

    This paper describes the first comparison of satellite radar and airborne laser altimetry over sea ice. In order to investigate the differences between measurements from the two different instruments we explore the statistical properties of the data and determine reasonable scales in space and ti...

  20. Comparison of Surface Elevation Changes of the Greenland and Antarctic Ice Sheets from Radar and Laser Altimetry

    Science.gov (United States)

    Zwally, H. Jay; Brenner, Anita C.; Barbieri, Kristine; DiMarzio, John P.; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui

    2012-01-01

    A primary purpose of satellite altimeter measurements is determination of the mass balances of the Greenland and Antarctic ice sheets and changes with time by measurement of changes in the surface elevations. Since the early 1990's, important measurements for this purpose have been made by radar altimeters on ERS-l and 2, Envisat, and CryoSat and a laser altimeter on ICESat. One principal factor limiting direct comparisons between radar and laser measurements is the variable penetration depth of the radar signal and the corresponding location of the effective depth of the radar-measured elevation beneath the surface, in contrast to the laser-measured surface elevation. Although the radar penetration depth varies significantly both spatially and temporally, empirical corrections have been developed to account for this effect. Another limiting factor in direct comparisons is caused by differences in the size of the laser and radar footprints and their respective horizontal locations on the surface. Nevertheless, derived changes in elevation, dHldt, and time-series of elevation, H(t), have been shown to be comparable. For comparisons at different times, corrections for elevation changes caused by variations in the rate offrrn compaction have also been developed. Comparisons between the H(t) and the average dH/dt at some specific locations, such as the Vostok region of East Antarctic, show good agreement among results from ERS-l and 2, Envisat, and ICESat. However, Greenland maps of dHidt from Envisat and ICESat for the same time periods (2003-2008) show some areas of significant differences as well as areas of good agreement. Possible causes of residual differences are investigated and described.

  1. SAR processing with non-linear FM chirp waveforms.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2006-12-01

    Nonlinear FM (NLFM) waveforms offer a radar matched filter output with inherently low range sidelobes. This yields a 1-2 dB advantage in Signal-to-Noise Ratio over the output of a Linear FM (LFM) waveform with equivalent sidelobe filtering. This report presents details of processing NLFM waveforms in both range and Doppler dimensions, with special emphasis on compensating intra-pulse Doppler, often cited as a weakness of NLFM waveforms.

  2. High-power pulsed diode laser for automotive scanning radar sensor

    Science.gov (United States)

    Kimura, Yuji; Matsushita, Noriyuki; Kato, Hisaya; Abe, Katsunori; Atsumi, Kinya

    2000-02-01

    High performance pulsed AlGaAs/GaAs wide stripe diode laser has been developed for the automotive distance-measuring scanning radar sensor. The laser diode is required high output power of 15 W and a long time reliability in spite of being used in a harsh environment such as wide temperature range, mechanical vibrations at the front bumper and so on. The device is designed by employing a multiple quantum well structure as an active layer for high output power with low drive current and high temperature operations. Moreover we reduce catastrophic optical damage power level and control the beam divergence angle by introducing optimized optical waveguide layers. In the chips bonding part, we developed a new thin film Au-Sn-Ni solder system. The bonding temperature can be lowered by using this system, whereby the thermal damage to the laser diode can be reduced. Furthermore, highly stable bonding is carried out by improving wetting ability in this system. We have achieved more than 22 W light output power at 20A pulse current under room temperature and more than 16 W light output power under 90 degrees Celsius. High reliability over 10,000 hours is performed for automotive use under pulsed operation at 90 degrees Celsius, 50 ns pulse width, 8 kHz frequency and 15 W light output power.

  3. Feasibility study of synthetic aperture infrared laser radar techniques for imaging of static and moving objects.

    Science.gov (United States)

    Yoshikado, S; Aruga, T

    1998-08-20

    Techniques for two types of 10-mum band synthetic aperture infrared laser radar using a hypothetical reference point target (RPT) are presented. One is for imaging static objects with a single two-dimensional scanning aperture. Through the simple manipulation of a reference wave phase, a desired image can be obtained merely by the two-dimensional Fourier transformation of the correlator output between the intermediate frequency signals of the reference and object waves. The other, with a one-dimensional aperture array, is for moving objects that pass across the array direction without attitude change. We performed imaging by using a two-dimensional RPT correlation method. We demonstrate the capability of these methods for imaging and evaluate the necessary conditions for signal-to-noise ratio and random phase errors in signal reception through numerical simulations in terms of feasibility.

  4. A high sensitive 66 dB linear dynamic range receiver for 3-D laser radar

    Science.gov (United States)

    Ma, Rui; Zheng, Hao; Zhu, Zhangming

    2017-08-01

    This study presents a CMOS receiver chip realized in 0.18 μm standard CMOS technology and intended for high precision 3-D laser radar. The chip includes an adjustable gain transimpedance pre-amplifier, a post-amplifier and two timing comparators. An additional feedback is employed in the regulated cascode transimpedance amplifier to decrease the input impedance, and a variable gain transimpedance amplifier controlled by digital switches and analog multiplexer is utilized to realize four gain modes, extending the input dynamic range. The measurement shows that the highest transimpedance of the channel is 50 k {{Ω }}, the uncompensated walk error is 1.44 ns in a wide linear dynamic range of 66 dB (1:2000), and the input referred noise current is 2.3 pA/\\sqrt{{Hz}} (rms), resulting in a very low detectable input current of 1 μA with SNR = 5.

  5. FY05 FM Dial Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Harper, Warren W.; Strasburg, Jana D.; Golovich, Elizabeth C.; Thompson, Jason S.; Stewart, Timothy L.; Batdorf, Michael T.

    2005-12-01

    Pacific Northwest National Laboratory's Infrared Sensors team is focused on developing methods for standoff detection of nuclear proliferation. In FY05, PNNL continued the development of the FM DIAL (frequency-modulated differential absorption LIDAR) experiment. Additional improvements to the FM DIAL trailer provided greater stability during field campaigns which made it easier to explore new locations for field campaigns. In addition to the Hanford Townsite, successful experiments were conducted at the Marine Science Laboratory in Sequim, WA and the Nevada Test Site located outside Las Vegas, NV. The range of chemicals that can be detected by FM DIAL has also increased. Prior to FY05, distributed feedback quantum cascade lasers (DFB-QCL) were used in the FM DIAL experiments. With these lasers, only simple chemicals with narrow (1-2 cm-1) absorption spectra, such as CO2 and N2O, could be detected. Fabry-Perot (FP) QC lasers have much broader spectra (20-40 cm-1) which allows for the detection of larger chemicals and a wider array of chemicals that can be detected. A FP-QCL has been characterized and used during initial studies detecting DMMP (dimethyl methylphosphonate).

  6. Laser-radar-based three-dimensional sensor for teaching robot paths

    Science.gov (United States)

    Maekynen, Anssi J.; Kostamovaara, Juha T.; Myllyla, Risto A.

    1995-09-01

    Implementation and test results of a 3D sensor based on time-of-flight (TOF) laser radar are presented. A sensor capable of measuring 3D positions and orientations in a large working space is used for interactive teaching of robot paths and environments. It consists of a pointing device, a laser rangefinder, and a video tracker. The 3D position and orientation of the pointer are obtained by measuring the distance from two separate points on the pointer arm to a tracing receiver and by using the tracking-camera image for detecting the angle of the pointer on the plane that is perpendicular to the optical axis of the tracking system. The rangefinder uses a new active target operating principle, including fiber-coupled transmitters attached to the pointer arm. The distance and angle measurement accuracies were measured to be better than +/- 5 mm and +/- 5 deg in the ranges of 2.3 to 4.7 m and +/- 40 deg, respectively, using ordinary technology. The operating range is likely to be increased and the accuracy enhanced by using the latest state-of-the-art TOF rangefinding technique.

  7. Error Ellipsoid Analysis for the Diameter Measurement of Cylindroid Components Using a Laser Radar Measurement System.

    Science.gov (United States)

    Du, Zhengchun; Wu, Zhaoyong; Yang, Jianguo

    2016-05-19

    The use of three-dimensional (3D) data in the industrial measurement field is becoming increasingly popular because of the rapid development of laser scanning techniques based on the time-of-flight principle. However, the accuracy and uncertainty of these types of measurement methods are seldom investigated. In this study, a mathematical uncertainty evaluation model for the diameter measurement of standard cylindroid components has been proposed and applied to a 3D laser radar measurement system (LRMS). First, a single-point error ellipsoid analysis for the LRMS was established. An error ellipsoid model and algorithm for diameter measurement of cylindroid components was then proposed based on the single-point error ellipsoid. Finally, four experiments were conducted using the LRMS to measure the diameter of a standard cylinder in the laboratory. The experimental results of the uncertainty evaluation consistently matched well with the predictions. The proposed uncertainty evaluation model for cylindrical diameters can provide a reliable method for actual measurements and support further accuracy improvement of the LRMS.

  8. Simulation of a laser radar to improve visiblity measurements in dense fog

    Science.gov (United States)

    Streicher, Juergen

    1992-12-01

    Lidar is the short form of light detection and ranging. The first application of a lidar system was, as in the radar technique, the determination of the distance to large-sized particles (target recognition). Nowadays, it is of more interest to measure the structure of the atmosphere in far distances (remote sensing) to get, for example, information about the mass concentration of the industrial pollution or the visibility conditions in dense fog. In this case the action and reaction of the laser light with the particles is made by very small and different scatterers (molecules, atoms, or aerosols) and, therefore, extremely complex. A simulation program that helps to determine the visibility with a lidar has been developed to present the effects of the components of the system (laser, transmitter, receiver) as well as the parameters of the atmosphere (inhomogeneities, fog, clouds) in a convenient way. A change in any parameter is taken into account instantaneously, so this program can be called an almost real time simulator. A computer with a graphic user interface was chosen to realize this as simply as possible: The Commodore Amiga. The simulation is written in `C' to get the best performance for the calculations.

  9. Multi-channel photon counting three-dimensional imaging laser radar system using fiber array coupled Geiger-mode avalanche photodiode

    Science.gov (United States)

    Shu, Rong; Huang, Genghua; Hou, Libing; He, Zhiping; Hu, Yihua

    2012-09-01

    Photon counting laser radar is the most sensitive and efficiency detection method of direct-detection laser radar. With the use of Geiger-mode avalanche photodiode (APD) or other single photon detectors, every laser photon could be sufficiently used for ranging and three-dimensional imaging. The average energy of received laser signal could be as low as a single photon, or even less than one. This feature of photon counting laser radar enables ranging under conditions of long range, low laser pulse energy, and multi-pixel detection, while receiver size, mass, power, and complexity of laser radar are reduced. In this paper, a latest multi-channel photon counting 3D imaging laser radar system using fiber array coupled Geiger-mode avalanche photodiode (APD) is introduced. Detection model based on Poisson statistics of a photon counting laser radar is discussed. A laser radar system, working under daylight condition with ultra-low signal level (less than single photon per pulse), has been designed and analyzed with the detection model and photon counting three-dimensional imaging theory. A passively Q-switched microchip laser is used to transmit short sub-nanosecond laser pulses at 532nm. The output laser is divided into 1×8 laser spots, which correspond to 8 Geiger-mode avalanche photodiodes coupled by a 1×8-pixel fiber array. A FPGA based time-to-digital converter (TDC), which is designed by delay line interpolation technology, is used for multi-hit signal acquisition. The algorithm of photon counting three-dimensional imaging is developed for signal photon events extraction and noise filter. Three-dimensional images under daylight conditions were acquired and analyzed. The results show that system could operate at strong solar background. The ranging accuracy of the system is 6.3cm (σ) while received laser pulse signal level is only 0.04 photoelectrons on average. The advantages and feasibility of photon counting laser radar working at daylight have been

  10. High-resolution laser radar for 3D imaging in artwork cataloging, reproduction, and restoration

    Science.gov (United States)

    Ricci, Roberto; Fantoni, Roberta; Ferri de Collibus, Mario; Fornetti, Giorgio G.; Guarneri, Massimiliano; Poggi, Claudio

    2003-10-01

    A high resolution Amplitude Modulated Laser Radar (AM-LR) sensor has recently been developed, aimed at accurately reconstructing 3D digital models of real targets, either single objects or complex scenes. The sensor sounding beam can be swept linearly across the object or circularly around it, by placing the object on a controlled rotating platform, enabling to obtain respectively linear and cylindrical range maps. Both amplitude and phase shift of the modulating wave of back-scattered light are collected and processed, providing respectively a shade-free, high resolution, photographic-like picture and accurate range data in the form of a range image. The resolution of range measurements depends mainly on the laser modulation frequency, provided that the power of the backscattered light reaching the detector is at least a few nW (current best performances are ~100 μm). The complete object surface can be reconstructed from the sampled points by using specifically developed software tools. The system has been successfully applied to scan different types of real surfaces (stone, wood, alloys, bones), with relevant applications in different fields, ranging from industrial machining to medical diagnostics, to vision in hostile environments. Examples of artwork reconstructed models (pottery, marble statues) are presented and the relevance of this technology for reverse engineering applied to cultural heritage conservation and restoration are discussed. Final 3D models can be passed to numeric control machines for rapid-prototyping, exported in standard formats for CAD/CAM purposes and made available on the Internet by adopting a virtual museum paradigm, thus possibly enabling specialists to perform remote inspections on high resolution digital reproductions of hardly accessible masterpieces.

  11. Full Waveform Analysis for Long-Range 3D Imaging Laser Radar

    Directory of Open Access Journals (Sweden)

    Wallace AndrewM

    2010-01-01

    Full Text Available The new generation of 3D imaging systems based on laser radar (ladar offers significant advantages in defense and security applications. In particular, it is possible to retrieve 3D shape information directly from the scene and separate a target from background or foreground clutter by extracting a narrow depth range from the field of view by range gating, either in the sensor or by postprocessing. We discuss and demonstrate the applicability of full-waveform ladar to produce multilayer 3D imagery, in which each pixel produces a complex temporal response that describes the scene structure. Such complexity caused by multiple and distributed reflection arises in many relevant scenarios, for example in viewing partially occluded targets, through semitransparent materials (e.g., windows and through distributed reflective media such as foliage. We demonstrate our methodology on 3D image data acquired by a scanning time-of-flight system, developed in our own laboratories, which uses the time-correlated single-photon counting technique.

  12. Novel eye-safe line scanning 3D laser-radar

    Science.gov (United States)

    Eberle, B.; Kern, Tobias; Hammer, Marcus; Schwanke, Ullrich; Nowak, Heinrich

    2014-10-01

    Today, the civil market provides quite a number of different 3D-Sensors covering ranges up to 1 km. Typically these sensors are based on single element detectors which suffer from the drawback of spatial resolution at larger distances. Tasks demanding reliable object classification at long ranges can be fulfilled only by sensors consisting of detector arrays. They ensure sufficient frame rates and high spatial resolution. Worldwide there are many efforts in developing 3D-detectors, based on two-dimensional arrays. This paper presents first results on the performance of a recently developed 3D imaging laser radar sensor, working in the short wave infrared (SWIR) at 1.5 μm. It consists of a novel Cadmium Mercury Telluride (CMT) linear array APD detector with 384x1 elements at a pitch of 25 μm, developed by AIM Infrarot Module GmbH. The APD elements are designed to work in the linear (non-Geiger) mode. Each pixel will provide the time of flight measurement, and, due to the linear detection mode, allowing the detection of three successive echoes. The resolution in depth is 15 cm, the maximum repetition rate is 4 kHz. We discuss various sensor concepts regarding possible applications and their dependence on system parameters like field of view, frame rate, spatial resolution and range of operation.

  13. Using a neural networks algorithm for high-resolution imaging in pulsed laser radar

    Science.gov (United States)

    Joodaki, Mojtaba; Kompa, Guenter; Golam Arshad, Seyed M.; Ahmadi, Vahid; Moravvej-Farshi, Mohammed K.

    2001-11-01

    A new imaging method which can obtain the gray levels directly from the output waveform of Pulsed Laser Radar (PLR) is developed. A simple digital signal processing technique and multi layer perceptrons (MLP) type neural network (NN) have been used to obtain the gray level information from the pulse shapes. The method has been implemented in a real PLR to improve contrast and speed of 2D imaging in PLR. To compare the method with the standard method, a picture consists of 16 gray levels (from 0 for black to 1 for white) with both method has been scanned. Because of the ability of NNs in extracting the information from nonlinear and noisy data and preprocessing of the noisy input pulse shapes to the NN, the average and maximum of errors in the gray levels in comparison with standard method more than 88.5% and 72.6% improved, respectively. Because in this method the effect of the noise is decreased, it is possible to make the imaging with the same resolution as in standard method but with a lower averaging in sampling unit and this dramatically increases speed of the measurements.

  14. Verification measurements of the Karoo Array timing system: a laser radar based time transfer system

    Science.gov (United States)

    Siebrits, R.; Bauermeister, E.; Gamatham, R.; Adams, G.; Malan, J. A.; Burger, J. P.; Kapp, F.; Gibbon, T.; Kriel, H.; Abbott, T.

    2016-02-01

    An optical fiber based laser radar time transfer system has been developed for the 64-dish MeerKAT radiointerferometer telescope project to provide accurate atomic time to the receivers of the telescope system. This time transfer system is called the Karoo Array Timing System (KATS). Calibration of the time transfer system is essential to ensure that time is accurately transferred to the digitisers that form part of the receivers. Frequency domain reflectometry via vector network analysers is also used to verify measurements taken using time interval counters. This paper details the progress that is made in the verification measurements of the system in order to ensure that time, accurate to within a few nanoseconds of the Universal Coordinated Time (UTC, is available at the point where radio signals from astronomical sources are received. This capability enables world class transient and timing studies with a compact radio interferometer, which has inherent advantages over large single dish radio-telescopes, in observing the transient sky.

  15. Digital Elevation Models of Greenland based on combined radar and laser altimetry as well as high-resolution stereoscopic imagery

    Science.gov (United States)

    Levinsen, J. F.; Smith, B. E.; Sandberg Sorensen, L.; Khvorostovsky, K.; Simonsen, S. B.; Forsberg, R.

    2015-12-01

    A number of Digital Elevation Models (DEMs) of Greenland exist, each of which are applicable for different purposes. This study presents two such DEMs: One developed by merging contemporary radar and laser altimeter data, and one derived from high-resolution stereoscopic imagery. All products are made freely available. The former DEM covers the entire Greenland. It is specific to the year 2010, providing it with an advantage over previous models suffering from either a reduced spatial/ temporal data coverage or errors from surface elevation changes (SEC) occurring during data acquisition. Radar data are acquired with Envisat and CryoSat-2, and laser data with the Ice, Cloud, and land Elevation Satellite, the Land, Vegetation, and Ice Sensor, and the Airborne Topographic Mapper. Correcting radar data for errors from slope effects and surface penetration of the echoes, and merging these with laser data, yields a DEM capable of resolving both surface depressions as well as topographic features at higher altitudes. The spatial resolution is 2 x 2 km, making the DEM ideal for application in surface mass balance studies, SEC detection from radar altimetry, or for correcting such data for slope-induced errors. The other DEM is developed in a pilot study building the expertise to map all ice-free parts of Greenland. The work combines WorldView-2 and -3 as well as GeoEye1 imagery from 2014 and 2015 over the Disko, Narsaq, Tassilaq, and Zackenberg regions. The novelty of the work is the determination of the product specifications after elaborate discussions with interested parties from government institutions, the tourist industry, etc. Thus, a 10 m DEM, 1.5 m orthophotos, and vector maps are produced. This opens to the possibility of using orthophotos with up-to-date contour lines or for deriving updated coastlines to aid, e.g., emergency management. This allows for a product development directly in line with the needs of parties with specific interests in Greenland.

  16. Frequency-modulated continuous-wave laser radar using dual vertical-cavity surface-emitting laser diodes for real-time measurements of distance and radial velocity

    Science.gov (United States)

    Kakuma, Seiichi

    2017-02-01

    A frequency-modulated continuous-wave (FMCW) laser radar capable of real-time displaying the distance to a target object and its radial velocity as their corresponding frequency spectra is developed. The system employs a pair of oppositely frequency-swept vertical-cavity surface-emitting laser diodes (VCSELs). This makes possible simultaneous detection of beat signals induced by the increment (up-ramp) and decrement (down-ramp) in laser frequencies. By mixing these two beat signals, their sum and difference frequencies are directly obtained without arithmetic processing such as averaging and subtraction. Results of the test experiments adopting axially moving block gauges as target objects show that both the distance and given velocities are accurately determined from the spectrum of the frequency mixer.

  17. The irradiating field of view of imaging laser radar under fog conditions in a controlled laboratory environment

    Science.gov (United States)

    Song, Wen-Hua; Ghassemlooy, Zabih; Lai, Jian-Cheng; Yan, Wei; Wang, Chun-Yong; Li, Zhen-Hua

    2017-04-01

    This paper theoretically and experimentally investigates the performance of the imaging laser radar (ILR) system under the fog condition. Fog is generated and controlled homogeneously within a dedicated indoor atmospheric chamber. A physical model of the reflected laser pulses due to fog and a standard Lambertian target are developed to determine the width of each echo pulse for different fog concentrations. We show that there is a good agreement between the predicted and measured results for the width of backscattered return pulses. Based on experimental results an empirical model of the horizontal and vertical irradiating field of views (FOVs) of ILR under different visibilities is also developed. Consequently, a new model is proposed to predict the horizontal and vertical irradiating FOVs of ILR by using the width of the backscattered return pulse under different fog conditions. The reported results can be used to dynamically adjust the scanning interval based on the variation of the irradiating FOVs of laser radar and improve the precision of target ranging and imaging.

  18. FM consolidation plan

    CERN Document Server

    Nonis, M; CERN. Geneva. TS Department

    2008-01-01

    The average life duration of infrastructure being 30 years, preventive or corrective maintenance is not enough to guarantee the perpetuity of the operation of equipment and installation in order to assure the maintain of the patrimony in a functional state. At CERN, such is the age of the civil engineering infrastructure and the relative technical equipment that urgent and appropriate consolidation programs shall be established. The big number of aged buildings and equipment entails that priorities are defined. This paper realizes a portrait of the actual situation and related problems, based on data extracted from D7i and inventories carried out by TS/FM group; at the same time it defines an interventions planning which optimizes safety aspects and maintenance costs. The timing of these interventions depends on the availability of specific resources.

  19. Airborne laser scan data: a valuable tool with which to infer weather radar partial beam blockage in urban environments

    Science.gov (United States)

    Cremonini, Roberto; Moisseev, Dmitri; Chandrasekar, Venkatachalam

    2016-10-01

    High-spatial-resolution weather radar observations are of primary relevance for hydrological applications in urban areas. However, when weather radars are located within metropolitan areas, partial beam blockages and clutter by buildings can seriously affect the observations. Standard simulations with simple beam propagation models and digital elevation models (DEMs) are usually not able to evaluate buildings' contribution to partial beam blockages. In recent years airborne laser scanners (ALSs) have evolved to the state-of-the-art technique for topographic data acquisition. Providing small footprint diameters (10-30 cm), ALS data allow accurate reconstruction of buildings and forest canopy heights. Analyzing the three weather C-band radars located in the metropolitan area of Helsinki, Finland, the present study investigates the benefits of using ALS data for quantitative estimations of partial beam blockages. The results obtained applying beam standard propagation models are compared with stratiform 24 h rainfall accumulation to evaluate the effects of partial beam blockages due to constructions and trees. To provide a physical interpretation of the results, the detailed analysis of beam occultations is achieved by open spatial data sets and open-source geographic information systems.

  20. The Precision Expandable Radar Calibration Sphere (PERCS) With Applications for Laser Imaging and Ranging

    Science.gov (United States)

    2008-09-01

    HF facilities such as HAARP in Alaska, EISCAT in Norway, and Arecibo in Puerto Rico; (3) the chain of high latitude SuperDARN radars used for auroral...DF arrays, ground HF transmitters such as the Navy relocatable over the horizon radar (ROTHR) and the Air Force/Navy HAARP system would be employed...United States and Australia; (2) high power HF facilities such as HAARP in Alaska, EISCAT in Norway, and Arecibo in Puerto Rico; (3) the chain of high

  1. Improved PLL For FM Demodulator

    Science.gov (United States)

    Kirkham, Harold; Jackson, Shannon P.

    1992-01-01

    Phase-locked loop (PLL) for frequency demodulator contains improved frequency-to-voltage converter producing less ripple than conventional phase detector. In improved PLL, phase detector replaced by state estimator, implemented by ramp/sample-and-hold circuit. Intended to reduce noise in receiver of frequency-modulated (FM) telemetry link without sacrificing bandwidth. Also applicable to processing received FM signals.

  2. Laser radar studies: A study of the feasibility of remote measurement of atmospheric density and turbidity by means of rotational Raman scattering of laser light

    Science.gov (United States)

    Reiss, N.; Schotland, R. M.

    1973-01-01

    A remote sensing technique is described which utilizes elastic scattering and rotational Raman scattering of laser light in the atmosphere to obtain soundings of turbidity, transmissivity and density. A scheme is devised whereby, through selective weighting of the rotational Raman lines, the effect of atmospheric temperature structure may be eliminated. The close spectral proximity of the elastic and Raman-scattered signals, combined with the fact that the Raman scattering is quite weak, produces special requirements for the spectroscopic and light-gathering components of a rotational Raman laser radar system. These requirements are investigated. A computation of typical signal-to-noise ratios is made. It is shown that daytime signal-to-noise ratios greater than 10 db are to be expected for observation heights of 5 km and below. For nighttime work, 10 db signal-to-noise ratios are achievable to altitudes as high as 15 km.

  3. ESA CryoVEx 2014 - Airborne ASIRAS radar and laser scanner measurements during 2014 CryoVEx campaign in the Arctic

    DEFF Research Database (Denmark)

    Hvidegaard, S. M.; Nielsen, J. E.; Sørensen, L. Sandberg;

    This report outlines the airborne field operations with the ESA airborne Ku‐band interferometric radar (ASIRAS), coincident airborne laser scanner (ALS) and vertical photography to acquire data over sea‐ and land ice along validation sites and CryoSat‐2 ground tracks. The airborne campaign was co...

  4. Nonlinear automatic landing control of unmanned aerial vehicles on moving platforms via a 3D laser radar

    Science.gov (United States)

    Hervas, Jaime Rubio; Reyhanoglu, Mahmut; Tang, Hui

    2014-12-01

    This paper presents a motion tracking and control system for automatically landing Unmanned Aerial Vehicles (UAVs) on an oscillating platform using Laser Radar (LADAR) observations. The system itself is assumed to be mounted on a ship deck. A full nonlinear mathematical model is first introduced for the UAV. The ship motion is characterized by a Fourier transform based method which includes a realistic characterization of the sea waves. LADAR observation models are introduced and an algorithm to process those observations for yielding the relative state between the vessel and the UAV is presented, from which the UAV's state relative to an inertial frame can be obtained and used for feedback purposes. A sliding mode control algorithm is derived for tracking a landing trajectory defined by a set of desired waypoints. An extended Kalman filter (EKF) is proposed to account for process and observation noises in the design of a state estimator. The effectiveness of the control algorithm is illustrated through a simulation example.

  5. Design of indoor laser radar navigation system%室内激光雷达导航系统设计

    Institute of Scientific and Technical Information of China (English)

    史风栋; 刘文皓; 汪鑫; 丁娟; 史屹君; 修春波

    2015-01-01

    With the rapid development of micro aerial vehicle technology and mobile robots technology, the requirements for indoor navigation technology are becoming higher and higher, but navigation presence is low and equipment is relatively complex in indoor navigation system. To address this problem, an indoor active navigation method that combines laser radar positioning and geomagnetic sensors measurement was proposed. First, laser radar was used to scan the indoor environment, the map be constructed by collected data, the route be planed based on the destination information and the indoor environment information; and then the data which was obtained by laser radar continuously scanning environment was compared with the map data when the vehicle was traveling, the location was determined, direction of travel was obtained by geomagnetic sensor, whether the vehicle was on the right road was determined by the combination of position and direction of travel, the deviation will be corrected in time; last, whether arriving at designated location was determined by searching RFID landmarks. Simulation and experimental results show that the indoor laser radar navigation system is simple and the reliability is high, which meet the requirements of indoor navigation.%小型无人机和移动机器人技术迅速发展,对室内导航技术的要求越来越高,针对当前室内导航精度不高、导航设备比较复杂的问题,提出一种采用激光雷达定位和地磁传感器检测相结合的室内主动导航方法.该方法首先使用激光雷达扫描室内环境,用采集到的数据拟合出室内地图,根据目的地信息和室内的环境信息来规划行进的路线;然后在行进中使用激光雷达连续地扫描得到数据与地图数据进行比较,来确定所处的位置,同时使用地磁传感器取得行驶的方向,二者相结合判断是否在规划的路线上行驶,及时地对出现的偏差进行纠正;最后通过搜索RFID地标确定

  6. The use of airborne laser data to calibrate satellite radar altimetry data over ice sheets

    DEFF Research Database (Denmark)

    Ekholm, Simon; Bamber, J.L.; Krabill, W.B.

    2002-01-01

    -correlated noise can be effectively removed by the so-called relocation error correction method. The adjustment, however, produces a different spatial sampling of the data, which introduces a non-negligible slope related bias to the computation of digital elevation models. In this paper we incorporate high......Satellite radar altimetry is the most important data source for ice sheet elevation modeling but it is well established that the accuracy of such data from satellite borne radar altimeters degrade seriously with increasing surface slope and level of roughness. A significant fraction of the slope...... as a linear function of surface slope. This linear correspondence is in turn tested as a model for adjusting the satellite altimetry data for the observed slope correlated bias. The adjustment is shown to have a significant effect in terms of reducing the bias, thus improving the modeling accuracy of the data....

  7. ESA's Ice Sheets CCI: validation and inter-comparison of surface elevation changes derived from laser and radar altimetry over Jakobshavn Isbræ, Greenland – Round Robin results

    DEFF Research Database (Denmark)

    Fredenslund Levinsen, Joanna; Khvorostovsky, K.; Ticconi, F.

    2013-01-01

    GrIS analysis stem from the radar altimeters on-board Envisat, ERS-1 and ERS-2. The accuracy of laser data exceeds that of radar altimetry; the Round Robin analysis has, however, proven the latter equally capable of dealing with surface topography thereby making such data applicable in SEC analyses...

  8. 激光雷达散射截面测量不确定度理论分析%Analysis of measurement uncertainty of laser radar cross section

    Institute of Scientific and Technical Information of China (English)

    周亚凡; 刘颖; 叶宗民

    2013-01-01

    依据辐射传输与测量和标定原理,推导出激光雷达散射截面测量数学模型与不确定度表达式,对影响测量不确定度因素进行了较全面的分析,并提出修正与提高方法.%In this paper,we focus on measurement uncertainty of laser radar cross section.Firstly,based on the principle of radiation measurement and calibration,mathematic model and uncertainty expression of laser radar cross section are derived.Then the factors that affect the uncertainty of measurement are analyzed.Finally,the correction method is proposed.

  9. Terahertz inverse synthetic aperture radar (ISAR) imaging with a quantum cascade laser transmitter.

    Science.gov (United States)

    Danylov, Andriy A; Goyette, Thomas M; Waldman, Jerry; Coulombe, Michael J; Gatesman, Andrew J; Giles, Robert H; Qian, Xifeng; Chandrayan, Neelima; Vangala, Shivashankar; Termkoa, Krongtip; Goodhue, William D; Nixon, William E

    2010-07-19

    A coherent transceiver using a THz quantum cascade (TQCL) laser as the transmitter and an optically pumped molecular laser as the local oscillator has been used, with a pair of Schottky diode mixers in the receiver and reference channels, to acquire high-resolution images of fully illuminated targets, including scale models and concealed objects. Phase stability of the received signal, sufficient to allow coherent image processing of the rotating target (in azimuth and elevation), was obtained by frequency-locking the TQCL to the free-running, highly stable optically pumped molecular laser. While the range to the target was limited by the available TQCL power (several hundred microwatts) and reasonably strong indoor atmospheric attenuation at 2.408 THz, the coherence length of the TQCL transmitter will allow coherent imaging over distances up to several hundred meters. Image data obtained with the system is presented.

  10. Towards Quantitative Optical Cross Sections in Entomological Laser Radar - Potential of Temporal and Spherical Parameterizations for Identifying Atmospheric Fauna.

    Directory of Open Access Journals (Sweden)

    Mikkel Brydegaard

    Full Text Available In recent years, the field of remote sensing of birds and insects in the atmosphere (the aerial fauna has advanced considerably, and modern electro-optic methods now allow the assessment of the abundance and fluxes of pests and beneficials on a landscape scale. These techniques have the potential to significantly increase our understanding of, and ability to quantify and manage, the ecological environment. This paper presents a concept whereby laser radar observations of atmospheric fauna can be parameterized and table values for absolute cross sections can be catalogued to allow for the study of focal species such as disease vectors and pests. Wing-beat oscillations are parameterized with a discrete set of harmonics and the spherical scatter function is parameterized by a reduced set of symmetrical spherical harmonics. A first order spherical model for insect scatter is presented and supported experimentally, showing angular dependence of wing beat harmonic content. The presented method promises to give insights into the flight heading directions of species in the atmosphere and has the potential to shed light onto the km-range spread of pests and disease vectors.

  11. Nonlinear automatic landing control of unmanned aerial vehicles on moving platforms via a 3D laser radar

    Energy Technology Data Exchange (ETDEWEB)

    Hervas, Jaime Rubio; Tang, Hui [School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798 (Singapore); Reyhanoglu, Mahmut [Physical Sciences Department, Embry-Riddle Aeronautical University, Daytona Beach, FL 32114 (United States)

    2014-12-10

    This paper presents a motion tracking and control system for automatically landing Unmanned Aerial Vehicles (UAVs) on an oscillating platform using Laser Radar (LADAR) observations. The system itself is assumed to be mounted on a ship deck. A full nonlinear mathematical model is first introduced for the UAV. The ship motion is characterized by a Fourier transform based method which includes a realistic characterization of the sea waves. LADAR observation models are introduced and an algorithm to process those observations for yielding the relative state between the vessel and the UAV is presented, from which the UAV's state relative to an inertial frame can be obtained and used for feedback purposes. A sliding mode control algorithm is derived for tracking a landing trajectory defined by a set of desired waypoints. An extended Kalman filter (EKF) is proposed to account for process and observation noises in the design of a state estimator. The effectiveness of the control algorithm is illustrated through a simulation example.

  12. FM Innovation in Science and Practice

    DEFF Research Database (Denmark)

    Mobach, Mark P.; Nardelli, Giulia; Konkol, Jennifer;

    2015-01-01

    Purpose : To report in FM Innovation. Theory : Innovation theory, service management, space design. Design/methodology/approach : Case studies, workshop. Findings : Barriers, areas of interest, and best practices in FM Innovation. Originality/value : Presents a first exploration of European case...... practices in FM Innovation....

  13. Improving Weather Radar Precipitation Estimates by Combining two Types of Radars

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ellerbæk; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

    2014-01-01

    the two radar types achieves a radar product with both long range and high temporal resolution. It is validated that the blended radar product performs better than the individual radars based on ground observations from laser disdrometers. However, the data combination is challenged by lower performance...

  14. A composite scanning method and experiment of laser radar%一种激光雷达复合式扫描方法及试验

    Institute of Scientific and Technical Information of China (English)

    马辰昊; 付跃刚; 宫平; 欧阳名钊; 张书瀚

    2015-01-01

    In traditional laser radar system, the imaging is influenced by repetition rate of selected solid-state laser as well as scanning bandwidth and scanning precision in the laser scanning system. In order to improve the scanning bandwidth and precision, DFB high-repetition-rate semiconductor laser which was amplified by EDFA was adopted as the laser source firstly. Secondly, a two-stage composite laser scanning method had been proposed with combination of PZT and galvanometer. PZT got on meticulous scanning in small areas, then galvanometer was used to deflect and finish coarse scanning on the PZT scanning field and receiving the field. The scanning accuracy had been raised and the scanning field of laser radar had been expanded simultaneously. At last, azimuth of composite scanning laser radar is ±99 mrad, pitch angle is ±49.5 mrad. Angular resolution can measure up to 0.1 mrad, and the ranging precision can reach 0.159 m.%传统激光雷达系统中,固态激光光源的重复频率和扫描系统的扫描带宽、精度均制约着系统成像.为提高激光雷达的成像精度,首先,在激光光源上采用经EDFA放大后的DFB高重频激光光源.其次,提出了一种PZT与振镜相结合的两级复合式激光扫描方法,利用PZT对小视场范围进行精细扫描,利用振镜对 PZT 的扫描视场和接收视场进行偏转完成粗扫描,在提高激光雷达扫描精度的同时拥有较大的扫描视场.最后,经试验所设计的复合式扫描激光雷达的方位角为±99 mrad,俯仰角为±49.5 mrad,角分辨率达到0.1 mrad,测距精度达到0.159 m.

  15. Doublet Pulse Coherent Laser Radar for Tracking of Resident Space Objects

    Science.gov (United States)

    Prasad, Narasimha S.; Rudd, Van; Shald, Scott; Sandford, Stephen; Dimarcantonio, Albert

    2014-01-01

    In this paper, the development of a long range ladar system known as ExoSPEAR at NASA Langley Research Center for tracking rapidly moving resident space objects is discussed. Based on 100 W, nanosecond class, near-IR laser, this ladar system with coherent detection technique is currently being investigated for short dwell time measurements of resident space objects (RSOs) in LEO and beyond for space surveillance applications. This unique ladar architecture is configured using a continuously agile doublet-pulse waveform scheme coupled to a closed-loop tracking and control loop approach to simultaneously achieve mm class range precision and mm/s velocity precision and hence obtain unprecedented track accuracies. Salient features of the design architecture followed by performance modeling and engagement simulations illustrating the dependence of range and velocity precision in LEO orbits on ladar parameters are presented. Estimated limits on detectable optical cross sections of RSOs in LEO orbits are discussed.

  16. Detection on micro-Doppler effect based on 1550 nm laser coherent radar

    Science.gov (United States)

    Jun, Zhang; Yang, Sun; Zenghui, Cao; Tengfei, Sun; Tiantian, Zheng

    2014-01-01

    A laser coherent detection system of 1550 nm wavelength was presented, and experimental research on detecting micro-Doppler effect in a dynamic target was developed. In this paper, the return signal in the time domain is decomposed into a set of components in different wavelet-scales by multi-resolution analysis, and the components are associated with the vibrational motions in a target. The micro-Doppler signatures are extracted by applying the reconstruction (inverse wavelet transform). During the course of the final data processing frequency analysis and time-frequency analysis are applied to analyze the vibrational signals and estimate the motion parameters successfully. The experimental results indicate that the micro-Doppler information in a moving can be effectively detected, and tiny vibrational signatures also can be acquired effectively by wavelet multi-resolution analysis and time-frequency analysis.

  17. DETECTION ON MICRO-DOPPLER EFFECT BASED ON LASER COHERENT RADAR

    Institute of Scientific and Technical Information of China (English)

    Sun Yang; Zhang Jun

    2012-01-01

    A laser coherent detection system of 1550 nm wavelength was presented,and experimental research on detecting micro-Doppler effect in a dynamic target was developed.In the study,the return signal in the time domain is decomposed into a set of components in different wavelet scales by multi-resolution wavelet analysis,and the components are associated with the vibrational motions in a target.Then micro-Doppler signatures are extracted by applying the reconstruction.During the course of the final data processing frequency analysis and time-frequency analysis are applied to analyze the vibrational signals and estimate the motion parameters successfully.The experimental results indicate that the system can effectively detect micro-Doppler information in a moving target,and the tiny vibrational signatures also can be acquired effectively by wavelet multi-resolution analysis and time-frequency analysis.

  18. Planetary boundary layer (PBL) monitoring by means of two laser radar systems: experimental results and comparison

    Science.gov (United States)

    Bellecci, C.; Gaudio, P.; Gelfusa, M.; Malizia, A.; Richetta, M.; Serafini, C.; Ventura, P.

    2010-10-01

    The PBL is the lower layer of the atmosphere that is sensitive to the effect of the Earths surface, it controls the flow of heat and momentum between the surface and the free atmosphere, thus playing a key role in atmospheric circulation. At University of Rome "Tor Vergata", Quantum Electronic and Plasma Laboratories (EQP), two mobile Light Detection and Ranging (LIDAR) systems have been developed. With these systems the monitoring of the Planetary Boundary Layer (PBL) has been performed. The first mobile Lidar system is based on a pulsed Nd:YAG Q-Switched laser source operating at three wavelengths: 1064 nm, 532 nm and 355 nm. Acquiring the elastic backscattered signals, it has been possible to estimate the aerosolitic backscattering coefficient at the aim to reconstruct the vertical aerosol profiles. The second one is a Differential Absorption Lidar system (DIAL), composed by a CO2 laser, working in the window spectral range between 9 and 11μm. With this system it has been estimated the water vapour concentration in the PBL region using the two wavelengths 10R20 (10.591 μm) and 10R18 (10.571 μm), which represent, respectively, the absorbing wavelength and non-absorbing one of the water molecule. The comparison of the backscattered radiation at these wavelengths yields the trace gas number density as a function of distance along the field-of-view of the receiving telescope. Diurnal and nocturnal measurements have been performed simultaneity using the two Lidar/Dial systems. Vertical profiles of the aerosolitic backscattering coefficient and water vapour concentration profiles have been estimated. The results and their comparison will be present in this work.

  19. Generating Contour Lines Based on Point Cloud Data of Laser Radar%基于激光雷达点云数据生成等高线

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    The paper was introduced process of generating contour line by using laser radar, and verified accuracy of contour line from aspects of coordinate conversion and re-framing of point cloud data.%  从坐标转换、点云数据重新分幅等方面介绍了利用激光雷达点云数据生成等高线的流程,并对等高线生成后的精度进行校验。

  20. Profiling value added position in FM

    DEFF Research Database (Denmark)

    Katchamart, Akarapong

    organizations can best add value. Based on comprehensive literature studies and 7 case studies of private and public organisations from Denmark, Holland, Hong Kong and Thailand, the dissertation analyses, how FM organizations can best create added value. From the analyses the following four value added...... - FM organizations influence the business productivities and outcome Each type of value added requires specific conditions and contingencies involved. This research thus offers a visual aid tool, “FM product-process matrix”, to assist practitioners to indicate their existing circumstances and contexts...... the unarticulated notions of added value from FM organization and activities. It will broaden the managerial perception and discussion on FM provision ´s abilities and capabilities. The results are besides the field of FM also of relevance for management of other service industries and functions....

  1. KARAKTERISTIK BAHASA PENYIAR RADIO JPI FM SOLO

    Directory of Open Access Journals (Sweden)

    Muhammad Rohmadi

    2004-06-01

    Full Text Available Bahasa adalah alat komunikasi yang digunakan penyiar Radio JPI FM Solo untuk berkomunikasi dengan para pendengarnya. Bahasa penyiar radio memiliki berbagai variasi dan karakter tersendiri dibandingkan bahasa-bahasa yang digunakan dalam ranah pendidikan, pemerintahan, dan keluarga. Karakteristik ragam bahasa penyiar Radio JPI FM Solo diwarnal campur kode, alih kode, dan nuansa humor dalam siarannya. Tujuan utama penyiar Radio JPI FM Solo adalah untuk menarik simpati pendengar dan berinteraksi dengan para pendengar Radio JPI FM Solo secara kreatif. Selain itu, ragam bahasa penyiar Radio JPI FM Solo memanfatkan beberapa fungsi utama ketika berkomunikasi dengan pendengarnya. Fungsi-fungsi tersebut adalah fungsi puitik, fungsi direktif, fungsi fatis, fungsi ekspresif, dan fungsi referensial dalam siaran Radio JPI FM Solo.

  2. The concept of added value of FM

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: This chapter presents research perspectives and theoretical reflections on the concept of added value of FM from a variety of academic fields. Methodology: A literature review of the most influential journals within the academic fields of Facilities Management (FM), Corporate Real Estate...... conceptualization of the concept of added value of FM is of utmost importance for further research into the added value of FM and well-considered, evidence- based Value Adding Management in practice. Research limitations: Due to limited time not all FM-related journals could be included in the literature review...... Management (CREM) and Business to Business Marketing (B2B Marketing). Findings: The research shows different definitions and focus points, dependent on the academic field and the area of application. The different research perspectives explored a holistic view on the added value of FM by the integration...

  3. The making of the FM value map

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: To present the FM Value Map and the background, process and considerations of its development and to reflect on perspectives and limitations. Methodology: The FM Value Map was developed from cases studies as part of the research project Facilities Management Best Practice in the Nordic....... Practical implications: The FM Value Map is a conceptual framework which can help to understand and explain the different ways that FM can create and add value to a core business and possibly to the surroundings. Furthermore, the value map may be used to identify and demonstrate the elements which...

  4. Autofocus technique for three-dimensional imaging, direct-detection laser radar using Geiger-mode avalanche photodiode focal-plane array.

    Science.gov (United States)

    Oh, Min Seok; Kong, Hong Jin; Kim, Tae Hoon; Jo, Sung Eun

    2010-12-15

    An autofocus technique is proposed for a three-dimensional imaging, direct-detection laser radar system that uses a Geiger-mode avalanche photodiode focal plane array (GmAPD-FPA). This technique is implemented by pointing laser pulses on a target of interest and observing its scattered photon distribution on a GmAPD-FPA. Measuring the standard deviation of the photon distribution on a GmAPD-FPA enables the best focus condition to be found. The feasibility of this technique is demonstrated experimentally by employing a 1 × 8 pixel GmAPD-FPA. It is shown that the spatial resolution improves when the GmAPD-FPA is located in the best focus position found by the autofocus technique.

  5. Use of 3D laser radar for navigation of unmanned aerial and ground vehicles in urban and indoor environments

    Science.gov (United States)

    Uijt de Haag, Maarten; Venable, Don; Smearcheck, Mark

    2007-04-01

    This paper discusses the integration of Inertial measurements with measurements from a three-dimensional (3D) imaging sensor for position and attitude determination of unmanned aerial vehicles (UAV) and autonomous ground vehicles (AGV) in urban or indoor environments. To enable operation of UAVs and AGVs at any time in any environment a Precision Navigation, Attitude, and Time (PNAT) capability is required that is robust and not solely dependent on the Global Positioning System (GPS). In urban and indoor environments a GPS position capability may not only be unavailable due to shadowing, significant signal attenuation or multipath, but also due to intentional denial or deception. Although deep integration of GPS and Inertial Measurement Unit (IMU) data may prove to be a viable solution an alternative method is being discussed in this paper. The alternative solution is based on 3D imaging sensor technologies such as Flash Ladar (Laser Radar). Flash Ladar technology consists of a modulated laser emitter coupled with a focal plane array detector and the required optics. Like a conventional camera this sensor creates an "image" of the environment, but producing a 2D image where each pixel has associated intensity vales the flash Ladar generates an image where each pixel has an associated range and intensity value. Integration of flash Ladar with the attitude from the IMU allows creation of a 3-D scene. Current low-cost Flash Ladar technology is capable of greater than 100 x 100 pixel resolution with 5 mm depth resolution at a 30 Hz frame rate. The proposed algorithm first converts the 3D imaging sensor measurements to a point cloud of the 3D, next, significant environmental features such as planar features (walls), line features or point features (corners) are extracted and associated from one 3D imaging sensor frame to the next. Finally, characteristics of these features such as the normal or direction vectors are used to compute the platform position and attitude

  6. The making of the FM value map

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: To present the FM Value Map and the background, process and considerations of its development and to reflect on perspectives and limitations. Methodology: The FM Value Map was developed from cases studies as part of the research project Facilities Management Best Practice in the Nordic...... it take the core business strategy as a starting point, and it is a fairly static framework. In spite of these limitations, the FM Value Map is an important element in the ongoing research and development in this area, but it should perhaps more be seen as a starting point rather than an end result...... in specific cases have a special importance for the value creation of FM. Research limitations: The chapter is a retrospective presentation of a research process. Originality/value: The chapter gives a detailed insight in the development process of the conceptual FM Value Map....

  7. FM research for practice in Denmark

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2012-01-01

    environment. FM started to be developed in practice with a strong focus on benchmarking and IT systems like CAFM. Around year 2000 a number of research and development project on Whole Life Costing was carried out and around 2005 there were some development projects and publications on new offices. Digital......Purpose: The purpose of this paper is to present an overview of research and development in the area of Facilities Management (FM) in Denmark. Background: Research in FM is a fairly new activity in Denmark, but there have during the 1980’s and 1990’s been a number of development activities...... on national level, which have had importance to constitute and form a professional basis for FM. Approach (Theory/Methodology): The paper provides a chronological overview of research and development activities related to FM over the last 30 years in Denmark, including CFM’s ongoing research projects. Results...

  8. FM Research for Practice in Denmark

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    environment. FM started to be developed in practice with a strong focus on benchmarking and IT systems like CAFM. Around year 2000 a number of research and development project on Whole Life Costing was carried out and around 2005 there were some development projects and publications on new offices. Digital......Purpose: The purpose of this paper is to present an overview of research and development in the area of Facilities Management (FM) in Denmark. Background: Research in FM is a fairly new activity in Denmark, but there have during the 1980’s and 1990’s been a number of development activities...... on national level, which have had importance to constitute and form a professional basis for FM. Approach (Theory/Methodology): The paper provides a chronological overview of research and development activities related to FM over the last 30 years in Denmark, including CFM’s ongoing research projects. Results...

  9. Train speed measurement system based on the scanning laser radar%基于扫描激光雷达的列车速度测量系统

    Institute of Scientific and Technical Information of China (English)

    刘常杰; 刘洪伟; 郭寅; 刘邈; 张宾; 叶声华

    2015-01-01

    Concerning the difficulties such as small measuring range and complicated operation in traditional train speed measure device, a new speed measuring system for dynamic clearance limit measurement of high-speed train is designed based on scanning laser radar. The scanning laser radar fixed in the position of 10 meters from the train. According to the principle of pulsed time-of-flight laser ranging, after the train enters the scan range the scanning laser radar scans the train point by point along the direction of train obtains the body contours. Process measurement data of cars with least square method to obtain the track and direction of the train. The travel distance of the train during two adjacent measurement cycle can be measured through piecewise linear interpolation. Complete the train speed measurement through the above work. Field experiments show that the system is easy to operate with capacity of 600 km/h and the system measurement error is less than 1.2% meets the demand of high-speed train velocity measurement.%针对传统列车速度测量装置存在量程小、调试复杂等问题,基于扫描激光雷达技术,设计了一套适用于高速列车动态限界测量的列车速度测量系统。将扫描激光雷达固定在距列车10 m左右的位置上,根据激光脉冲飞行时间测距原理,沿列车行驶方向对进入扫描范围内的列车车身逐点扫描,获得由测量点组成的车身轮廓信息;通过最小二乘拟合车厢测量点,得到列车行驶轨迹,确定列车行驶方向;采用分段线性差值确定相邻两次测量周期内列车行驶的距离,完成列车速度的测量。结果表明:该测速系统操作方便,量程可达600 km/h,测速误差控制在±1.2%以内,可以满足高速列车速度测量需求。

  10. Testing relativity again, laser, laser, laser, laser

    NARCIS (Netherlands)

    Einstein, A.

    2015-01-01

    laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser, laser,

  11. Quantum radar

    CERN Document Server

    Lanzagorta, Marco

    2011-01-01

    This book offers a concise review of quantum radar theory. Our approach is pedagogical, making emphasis on the physics behind the operation of a hypothetical quantum radar. We concentrate our discussion on the two major models proposed to date: interferometric quantum radar and quantum illumination. In addition, this book offers some new results, including an analytical study of quantum interferometry in the X-band radar region with a variety of atmospheric conditions, a derivation of a quantum radar equation, and a discussion of quantum radar jamming.This book assumes the reader is familiar w

  12. Passive Multistatic Detection of Maritime Targets using Opportunistic Radars

    Science.gov (United States)

    2014-03-01

    optimal configuration using MATLAB simulation. The simulation results are obtained using actual system parameters extracted from civil marine radar ...Bistatic Radar . Norwood, MA: Artech House, Technology Service Corporation, p. 1, 1995. [2] D. C. Jenn, Radar and Laser Cross Section Engineering...MULTISTATIC DETECTION OF MARITIME TARGETS USING OPPORTUNISTIC RADARS by Chong Sze Sing March 2014 Thesis Advisor: Herschel H. Loomis Co-Advisor

  13. Radar Chart

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Radar Chart collection is an archived product of summarized radar data. The geographic coverage is the 48 contiguous states of the United States. These hourly...

  14. Comparative research and its significance of deformation measurements by technologies of laser real-time holographic interferometry and radar differential interferometry

    Institute of Scientific and Technical Information of China (English)

    MAO Xian-jin; XU Zhao-yong; QIAN Jia-dong; HU Yi-li; YANG Run-hai; WANG Bin

    2006-01-01

    The principles and applications of laser real-time holographic interferometry (LRTHI) and radar differential interferometry (RDI) technologies are described in this paper, respectively. By using LRTHI, we can observe the deformation of samples under pressure in the lab and study the anomaly characteristics relating to different strain fields in different fracture-developing areas; while by using RDI, we can observe the landform and surface deformation. The results of deformation observed before and after the Ms=7.9 Mani earthquake (Tibet) and Ms=6.2Shangyi-Zhangbei earthquake in China are obtained. It is pointed out that LRTHI and RDI are similar, which study the characteristics of anomalous deformation field by fringe variations for both of them. Therefore, the observation of deformation field in the seismogenic process, especially in the period impending an earthquake by RDI, and the comparative study in the lab by LRTHI are of great significance.

  15. Comparative research and its significance of deformation measurements by technologies of laser real-time holographic interferometry and radar differential interferometry

    Science.gov (United States)

    Mao, Xian-Jin; Xu, Zhao-Young; Qian, Jia-Dong; Hu, Yi-Li; Yang, Run-Hai; Wang, Bin

    2006-05-01

    The principles and applications of laser real-time holographic interferometry (LRTHI) and radar differential interferometry (RDI) technologies are described in this paper, respectively. By using LRTHI, we can observe the deformation of samples under pressure in the lab and study the anomaly characteristics relating to different strain fields in different fracture-developing areas; while by using RDI, we can observe the landform and surface deformation. The results of deformation observed before and after the M S=7.9 Mani earthquake (Tibet) and M S=6.2 Shangyi-Zhangbei earthquake in China are obtained. It is pointed out that LRTHI and RDI are similar, which study the characteristics of anomalous deformation field by fringe variations for both of them. Therefore, the observation of deformation field in the seismogenic process, especially in the period impending an earthquake by RDI, and the comparative study in the lab by LRTHI are of great significance.

  16. Radar Fundamentals, Presentation

    OpenAIRE

    Jenn, David

    2008-01-01

    Topics include: introduction, radar functions, antennas basics, radar range equation, system parameters, electromagnetic waves, scattering mechanisms, radar cross section and stealth, and sample radar systems.

  17. Radar Fundamentals, Presentation

    OpenAIRE

    Jenn, David

    2008-01-01

    Topics include: introduction, radar functions, antennas basics, radar range equation, system parameters, electromagnetic waves, scattering mechanisms, radar cross section and stealth, and sample radar systems.

  18. DARC servis konvencionalne FM radio-difuzije / DARC service conventional FM radio broadcasting

    Directory of Open Access Journals (Sweden)

    Mladen Manjak

    2006-07-01

    Full Text Available Konvencionalna FM radio-difuzija može ponuditi dodatne servise uz pomoć podnosioca smještenih u slobodnom dijelu osnovnog opsega multipleksiranog signala. U radu su prikazane osnovne karakteristike DARC servisa FM radio-difuzije i njegove moguće primjene. / Conventional FM radio broadcasting can offer additional services by means of a subcarrier placed in a clear part of the beseband multiplex signal. This paper contains elementary characteristics of DARC service conventional FM radio broadcasting and possible applications.

  19. Radar equations for modern radar

    CERN Document Server

    Barton, David K

    2012-01-01

    Based on the classic Radar Range-Performance Analysis from 1980, this practical volume extends that work to ensure applicability of radar equations to the design and analysis of modern radars. This unique book helps you identify what information on the radar and its environment is needed to predict detection range. Moreover, it provides equations and data to improve the accuracy of range calculations. You find detailed information on propagation effects, methods of range calculation in environments that include clutter, jamming and thermal noise, as well as loss factors that reduce radar perfo

  20. The Use of Polysymptomatic Distress Categories in the Evaluation of Fibromyalgia (FM) and FM Severity

    Science.gov (United States)

    Wolfe, Frederick; Walitt, Brian T.; Rasker, Johannes J.; Katz, Robert S.; Hauser, Winfried

    2016-01-01

    Objective The polysymptomatic distress (PSD) scale is derived from variables used in the 2010 American College of Rheumatology (ACR) fibromyalgia (FM) criteria modified for survey and clinical research. The scale is useful in measuring the effect of PSD over the full range of pain-related clinical symptoms, not just in those who are FM criteria-positive. However, no PSD scale categories have been defined to distinguish severity of illness in FM or in those who do not satisfy the FM criteria. We analyzed the scale and multiple covariates to develop clinical categories and to further validate the scale. Methods FM was diagnosed according to the research criteria modification of the 2010 ACR FM criteria. We investigated categories in a large database of patients with pain (2732 with rheumatoid arthritis) and developed categories by using germane clinic variables that had been previously studied for severity groupings. By definition, FM cannot be diagnosed unless PSD is at least 12. Results Based on population categories, regression analysis, and inspections of curvilinear relationships, we established PSD severity categories of none (0–3), mild (4–7), moderate (8–11), severe (12–19), and very severe (20–31). Categories were statistically distinct, and a generally linear relationship between PSD categories and covariate severity was noted. Conclusion PSD categories are clinically relevant and demonstrate FM type symptoms over the full range of clinical illness. Although FM criteria can be clinically useful, there is no clear-cut symptom distinction between FM (+) and FM (−), and PSD categories can aid in more effectively classifying patients. PMID:26077414

  1. Synthetic aperture radar capabilities in development

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The Imaging and Detection Program (IDP) within the Laser Program is currently developing an X-band Synthetic Aperture Radar (SAR) to support the Joint US/UK Radar Ocean Imaging Program. The radar system will be mounted in the program`s Airborne Experimental Test-Bed (AETB), where the initial mission is to image ocean surfaces and better understand the physics of low grazing angle backscatter. The Synthetic Aperture Radar presentation will discuss its overall functionality and a brief discussion on the AETB`s capabilities. Vital subsystems including radar, computer, navigation, antenna stabilization, and SAR focusing algorithms will be examined in more detail.

  2. Imaging synthetic aperture radar

    Science.gov (United States)

    Burns, Bryan L.; Cordaro, J. Thomas

    1997-01-01

    A linear-FM SAR imaging radar method and apparatus to produce a real-time image by first arranging the returned signals into a plurality of subaperture arrays, the columns of each subaperture array having samples of dechirped baseband pulses, and further including a processing of each subaperture array to obtain coarse-resolution in azimuth, then fine-resolution in range, and lastly, to combine the processed subapertures to obtain the final fine-resolution in azimuth. Greater efficiency is achieved because both the transmitted signal and a local oscillator signal mixed with the returned signal can be varied on a pulse-to-pulse basis as a function of radar motion. Moreover, a novel circuit can adjust the sampling location and the A/D sample rate of the combined dechirped baseband signal which greatly reduces processing time and hardware. The processing steps include implementing a window function, stabilizing either a central reference point and/or all other points of a subaperture with respect to doppler frequency and/or range as a function of radar motion, sorting and compressing the signals using a standard fourier transforms. The stabilization of each processing part is accomplished with vector multiplication using waveforms generated as a function of radar motion wherein these waveforms may be synthesized in integrated circuits. Stabilization of range migration as a function of doppler frequency by simple vector multiplication is a particularly useful feature of the invention; as is stabilization of azimuth migration by correcting for spatially varying phase errors prior to the application of an autofocus process.

  3. 47 CFR 73.297 - FM stereophonic sound broadcasting.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM stereophonic sound broadcasting. 73.297... RADIO BROADCAST SERVICES FM Broadcast Stations § 73.297 FM stereophonic sound broadcasting. (a) An FM... broadcasting, equipment performance measurements must be made to ensure that the transmitted signal...

  4. Comparative Study on Cloud Parameter Estimation Among GOSAT/CAI, MODIS, CALIPSO/CALIOP and Landsat-8/OLI with Laser Radar: Lidar as Truth Data

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2016-10-01

    Full Text Available A comparative study on cloud parameter estimation among GOSAT/CAI, MODIS, CALIPSO/CALIOP and Landsat-8/OLI is carried out using Laser Radar: Lidar as a truth data. Optical depth, size distribution, as well as cirrus type of clouds are cloud parameters. In particular, cirrus cloud detection is tough issue. 1.38 µm channel is required for its detection. Although MODIS and Landsat-8/OLI have such channel, the other mission instruments, CAI and CALIPSO/CALIOP do not have such channel. As a truth data of cloud parameter, ground based Lidar is used in this comparative study. From the Lidar, backscattered echo signal and depolarization coefficient are obtained as a function of altitude. Therefore, cloud type, vertical profile can be derived from the Lidar data. CALIPSO/CALIOP is satellite based Lidar which allows observation of clouds from space. Although the directions of laser light emissions between CALIPSO/CALIOP and the ground based Lidar are different, their principles are same. Therefore, it is expected that CALIPSO/CALIOP data derived cloud parameters are similar to the ground based Lidar data derived cloud parameters. The experimental results show the aforementioned facts and are useful for improvement of cloud parameter estimation accuracy with several sensor data combinations.

  5. Planetary Radar

    Science.gov (United States)

    Neish, Catherine D.; Carter, Lynn M.

    2015-01-01

    This chapter describes the principles of planetary radar, and the primary scientific discoveries that have been made using this technique. The chapter starts by describing the different types of radar systems and how they are used to acquire images and accurate topography of planetary surfaces and probe their subsurface structure. It then explains how these products can be used to understand the properties of the target being investigated. Several examples of discoveries made with planetary radar are then summarized, covering solar system objects from Mercury to Saturn. Finally, opportunities for future discoveries in planetary radar are outlined and discussed.

  6. Receptores de radio monochip para FM

    OpenAIRE

    Miguel López, José María

    2005-01-01

    Este libro aborda de forma estructurada tanto los aspectos de diseño como los de realización de receptores de radio para la banda de FM. Tras unos primeros capítulos dedicados al estudio de las propiedades de la modulación de frecuencia y de los circuitos básicos que configuran un receptor de radio, se desarrolla un minucioso análisis de los circuitos integrados TDA7000/10/21. Paso a paso se muestra cómo diseñar con estos circuitos receptores de FM que, al requerir muy pocos ajustes, puede...

  7. Comparing Accuracy of Airborne Laser Scanning and TerraSAR-X Radar Images in the Estimation of Plot-Level Forest Variables

    Directory of Open Access Journals (Sweden)

    Juha Hyyppä

    2010-01-01

    Full Text Available In this study we compared the accuracy of low-pulse airborne laser scanning (ALS data, multi-temporal high-resolution noninterferometric TerraSAR-X radar data and a combined feature set derived from these data in the estimation of forest variables at plot level. The TerraSAR-X data set consisted of seven dual-polarized (HH/HV or VH/VV Stripmap mode images from all seasons of the year. We were especially interested in distinguishing between the tree species. The dependent variables estimated included mean volume, basal area, mean height, mean diameter and tree species-specific mean volumes. Selection of best possible feature set was based on a genetic algorithm (GA. The nonparametric k-nearest neighbour (k-NN algorithm was applied to the estimation. The research material consisted of 124 circular plots measured at tree level and located in the vicinity of Espoo, Finland. There are large variations in the elevation and forest structure in the study area, making it demanding for image interpretation. The best feature set contained 12 features, nine of them originating from the ALS data and three from the TerraSAR-X data. The relative RMSEs for the best performing feature set were 34.7% (mean volume, 28.1% (basal area, 14.3% (mean height, 21.4% (mean diameter, 99.9% (mean volume of Scots pine, 61.6% (mean volume of Norway spruce and 91.6% (mean volume of deciduous tree species. The combined feature set outperformed an ALS-based feature set marginally; in fact, the latter was better in the case of species-specific volumes. Features from TerraSAR-X alone performed poorly. However, due to favorable temporal resolution, satellite-borne radar imaging is a promising data source for updating large-area forest inventories based on low-pulse ALS.

  8. Studies on remote sensing method of particle size and water density distribution in mists and clouds using laser radar techniques

    Science.gov (United States)

    Shimizu, H.; Kobayasi, T.; Inaba, H.

    1979-01-01

    A method of remote measurement of the particle size and density distribution of water droplets was developed. In this method, the size of droplets is measured from the Mie scattering parameter which is defined as the total-to-backscattering ratio of the laser beam. The water density distribution is obtained by a combination of the Mie scattering parameter and the extinction coefficient of the laser beam. This method was examined experimentally for the mist generated by an ultrasonic mist generator and applied to clouds containing rain and snow. Compared with the conventional sampling method, the present method has advantages of remote measurement capability and improvement in accuracy.

  9. Validation of GPM Ka-Radar Algorithm Using a Ground-based Ka-Radar System

    Science.gov (United States)

    Nakamura, Kenji; Kaneko, Yuki; Nakagawa, Katsuhiro; Furukawa, Kinji; Suzuki, Kenji

    2016-04-01

    GPM led by the Japan Aerospace Exploration Agency (JAXA) and the National Aeronautics and Space Administration of US (NASA) aims to observe global precipitation. The core satellite is equipped with a microwave radiometer (GMI) and a dual-frequency radar (DPR) which is the first spaceborne Ku/Ka-band dual-wavelength radar dedicated for precipitation measurement. In the DPR algorithm, measured radar reflectivity is converted to effective radar reflectivity by estimating the rain attenuation. Here, the scattering/attenuation characteristics of Ka-band radiowaves are crucial, particularly for wet snow. A melting layer observation using a dual Ka-band radar system developed by JAXA was conducted along the slope of Mt. Zao in Yamagata Prefecture, Japan. The dual Ka-band radar system consists of two nearly identical Ka-band FM-CW radars, and the precipitation systems between two radars were observed in opposite directions. From this experiment, equivalent radar reflectivity (Ze) and specific attenuation (k) were obtained. The experiments were conducted for two winter seasons. During the data analyses, it was found that k estimate easily fluctuates because the estimate is based on double difference calculation. With much temporal and spatial averaging, k-Ze relationship was obtained for melting layers. One of the results is that the height of the peak of k seems slightly higher than that of Ze. The results are compared with in-situ precipitation particle measurements.

  10. Magnetostatic surface waves in an FM/LH/FM sandwiched structure

    Energy Technology Data Exchange (ETDEWEB)

    Ma Jianing; Li Hua; Zhang Qiang; Yin Yongqi; Wang Xuanzhang, E-mail: limjn@126.co [Provincial Key Laboratory for Advanced Functional Material and Excited States Processes, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025 (China)

    2010-07-15

    Properties of magnetostatic surface waves in a magnetic structure with one left-handed material (LHM) film sandwiched between two ferromagnetic (FM) films are discussed, where FM films are magnetized to be saturated by an external field parallel to the film surfaces and the LHM film has a constant and negative magnetic permeability. Besides the surface magnetostatic wave lying in the same frequency range as that of a single film, two new branches of surface magnetostatic waves with negative group velocity are found in different frequency ranges. The new branches propagate along the inner surface of an FM film, but the other propagates along the outer surface.

  11. All-optical bandwidth-tailorable radar

    CERN Document Server

    Zou, Weiwen; Long, Xin; Zhang, Siteng; Cui, Yuanjun; Chen, Jianping

    2015-01-01

    Radar has been widely used in military, security, and rescue. Metamaterial cloak is employed in stealth targets to evade radar detection. Hence modern radar should be reconfigurable at multi-bands for detecting stealth targets, which might be realized based on microwave photonics. Here, we demonstrate an all-optical bandwidth-tailorable radar architecture. It is a coherent system utilizing one mode-locked laser for both signal generation and reception. Heterodyning of two individually filtered optical pulses that are pre-chirped via wavelength-to-time mapping generates wideband linearly-chirped radar signal. The working bands can be flexibly tailored with desired bandwidth at user-preferred carrier frequency. After modulated onto the pre-chirped optical pulse, radar echoes are time-stretched and frequency-compressed by several times. The digitization becomes much easier without loss of detection ability. We believe that the demonstration can innovate the radar's architecture with ultra-high range resolution.

  12. Radar research at the University of Kansas

    Science.gov (United States)

    Blunt, Shannon D.; Allen, Christopher; Arnold, Emily; Hale, Richard; Hui, Rongqing; Keshmiri, Shahriar; Leuschen, Carlton; Li, Jilu; Paden, John; Rodriguez-Morales, Fernando; Salandrino, Alessandro; Stiles, James

    2017-05-01

    Radar research has been synonymous with the University of Kansas (KU) for over half a century. As part of this special session organized to highlight significant radar programs in academia, this paper surveys recent and ongoing work at KU. This work encompasses a wide breadth of sensing applications including the remote sensing of ice sheets, autonomous navigation methods for unmanned aerial vehicles (UAVs), novel laser radar capabilities, detection of highenergy cosmic rays using bistatic radar, different forms of waveform diversity such as MIMO radar and pulse agility, and various radar-embedded communication methods. The results of these efforts impact our understanding of the changing nature of the environment, address the proliferation of unmanned systems in the US airspace, realize new sensing modalities enabled by the joint consideration of electromagnetics and signal processing, and greater facilitate radar operation in an increasingly congested and contested spectrum.

  13. 激光雷达距离欺骗干扰技术研究%Research on deception jamming technology of laser radar

    Institute of Scientific and Technical Information of China (English)

    王萃; 张会彬

    2015-01-01

    This article mainly introduces the principle of laser ranging radar, the constituent parts of the laser rangefinder and the function of each part, and then this paper introduces a common method – the technology of Digital Radio Frequency Memory, expounding its deception principle of the false target and its working process for simulation. Research shows that using Digital Radio Frequency Memory technology can effectively carry out false targets deception. This technique can not only be used to cover the air defense, but also can be used for interfering with the enemy and decoying attack, exposing the real deployment of troops; therefore has considerable military significance.%文章主要介绍激光雷达测距的原理,激光测距机的组成及各部分的功能,根据其原理,介绍一种常用的距离欺骗的方法-数字储频技术,阐述其距离假目标欺骗的原理,对其工作过程进行仿真。研究表明,采用数字储频技术能够有效的进行欺骗,这种技术既可以用于掩护空防,又可以用于干扰敌方并诱敌开机,暴露其真实的兵力部署,因此具有相当大的军事意义。

  14. Laser doppler and radar interferometer for contactless measurements on unaccessible tie-rods on monumental buildings: Santa Maria della Consolazione Temple in Todi

    Science.gov (United States)

    Gioffré, M.; Cavalagli, N.; Pepi, C.; Trequattrini, M.

    2017-01-01

    Non-contact measurements can be effectively used in civil engineering to assess the variation of structural performance with time. In the last decades this approach has received considerable interests from researchers working in the field of structural health monitoring (SHM). Indeed, non-contact measurements are very attractive because it is possible to perform non intrusive and non destructive investigations even being at a significant distance from the targets. Within this context, contactless measurements of the tie-rod vibrations in the Santa Maria della Consolazione Temple in Todi (Italy) are presented in this paper. In particular, laser vibrometer and radar interferometer measurements are used to estimate natural frequencies and mode shapes. This information is crucial to obtain the tensile axial force in the tie-rods, which can be used as an indicator of structural integrity or possible failure. Furthermore, a novel approach is proposed where drones (Unmanned Aerial Vehicles) can be successfully used to improve the effectiveness and the accuracy of the experimental activities.

  15. An effective coded excitation scheme based on a predistorted FM signal and an optimized digital filter

    DEFF Research Database (Denmark)

    Misaridis, Thanasis; Jensen, Jørgen Arendt

    1999-01-01

    performed with the program Field II. A commercial scanner (B-K Medical 3535) was modified and interfaced to an arbitrary function generator along with an RF power amplifier (Ritec). Hydrophone measurements in water were done to establish excitation voltage and corresponding intensity levels (I-sptp and I......This paper presents a coded excitation imaging system based on a predistorted FM excitation and a digital compression filter designed for medical ultrasonic applications, in order to preserve both axial resolution and contrast. In radars, optimal Chebyshev windows efficiently weight a nearly...

  16. Cancer versus FM radio polarization types.

    Science.gov (United States)

    Hallberg, Örjan

    2016-07-01

    In 2002, a detailed analysis of skin melanoma in 289 Swedish municipalities showed a strong association with the number of horizontally polarized main FM transmitters covering a municipality. Basic antenna theory says that body-resonance and standing waves cannot appear above a metal spring mattress unless the electric field is horizontally polarized. To test the hypothesis that body-resonant radiation can cause increased cancer risk in other European countries, I collected and analysed reported data from 24 countries, among which six were using vertical polarization. The results showed a strong association between cancer risk and the use of horizontally polarized FM broadcasting radiation, whereas vertical polarization seemed to cause no health effects. This information should form the basis for initiating relevant corrective actions by responsible authorities.

  17. FM Radio and Youth: Listeners or Users?

    Directory of Open Access Journals (Sweden)

    Marina Mučalo

    2014-06-01

    Full Text Available A survey conducted in the spring of 2013, says that Zagreb’s high school students are not regular listeners to FM radio programs. The dominant media is the Internet, which is used a few hours a day, mostly for Facebook. Despite the expressed need for music, the linear and passive nature of FM radio, does not correspond to the individual requirements of young and networked users. The Internet is the most popular daily source for music, with ability to download, while smartphones are becoming devices for storage and playback. However, this survey has shown that students are interested in web radio sites. Changes in media preferences and habits caused by the Internet show us the importance of information literacy, as a basic skill for participation in a networked society.

  18. Efficient FM Algorithm for VLSI Circuit Partitioning

    Directory of Open Access Journals (Sweden)

    M.RAJESH

    2013-04-01

    Full Text Available In FM algorithm initial partitioning matrix of the given circuit is assigned randomly, as a result for larger circuit having hundred or more nodes will take long time to arrive at the final partition if theinitial partitioning matrix is close to the final partitioning then the computation time (iteration required is small . Here we have proposed novel approach to arrive at initial partitioning by using spectralfactorization method the results was verified using several circuits.

  19. FM-HD RADIO的应用

    Institute of Scientific and Technical Information of China (English)

    黄文海

    2014-01-01

    结合中央塔FM-HD RADIO发射机,就HD RADIO技术应用于FM频段部分的频谱结构、发射机改造等方面进行阐述,并利用北京地区的测试数据说明现阶段该技术在FM频段的应用.

  20. Wideband FM Demodulation and Multirate Frequency Transformations

    Science.gov (United States)

    2016-12-15

    the center frequency and bandwidth are manually assigned to each formant, which may incur serious distortion to the isolated resonance signal and... problem can be solved via populating the whole time- frequency space to take advantage of the dyadic filter bank behavior of the EMD. Currently, we only...AFRL-RV-PS- AFRL-RV-PS- TR-2016-0123 TR-2016-0123 WIDEBAND FM DEMODULATION AND MULTIRATE FREQUENCY TRANSFORMATIONS Balu Santhanam and Wenjing Liu

  1. 75 FR 19340 - FM TABLE OF ALLOTMENTS, Jewett, Texas

    Science.gov (United States)

    2010-04-14

    ... COMMISSION 47 CFR Part 73 FM TABLE OF ALLOTMENTS, Jewett, Texas AGENCY: Federal Communications Commission..., proposing the allotment of FM Channel 232A at Jewett, Texas, as a first local service. The reference.... Section 73.202(b), the Table of FM Allotments under Texas, is ameded by adding Jewett, Channe 232A...

  2. 47 CFR 73.599 - NCE-FM engineering charts.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false NCE-FM engineering charts. 73.599 Section 73.599 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Noncommercial Educational FM Broadcast Stations § 73.599 NCE-FM engineering charts. This...

  3. Weather Radar Stations

    Data.gov (United States)

    Department of Homeland Security — These data represent Next-Generation Radar (NEXRAD) and Terminal Doppler Weather Radar (TDWR) weather radar stations within the US. The NEXRAD radar stations are...

  4. Techniques for Effective Optical Noise Rejection in Amplitude-Modulated Laser Optical Radars for Underwater Three-Dimensional Imaging

    Directory of Open Access Journals (Sweden)

    Francucci M

    2010-01-01

    Full Text Available Amplitude-modulated (AM laser imaging is a promising technology for the production of accurate three-dimensional (3D images of submerged scenes. The main challenge is that radiation scattered off water gives rise to a disturbing signal (optical noise that degrades more and more the quality of 3D images for increasing turbidity. In this paper, we summarize a series of theoretical findings, that provide valuable hints for the development of experimental methods enabling a partial rejection of optical noise in underwater imaging systems. In order to assess the effectiveness of these methods, which range from modulation/demodulation to polarimetry, we carried out a series of experiments by using the laboratory prototype of an AM 3D imager ( = 405 nm for marine archaeology surveys, in course of realization at the ENEA Artificial Vision Laboratory (Frascati, Rome. The obtained results confirm the validity of the proposed methods for optical noise rejection.

  5. Techniques for Effective Optical Noise Rejection in Amplitude-Modulated Laser Optical Radars for Underwater Three-Dimensional Imaging

    Directory of Open Access Journals (Sweden)

    R. Ricci

    2010-01-01

    Full Text Available Amplitude-modulated (AM laser imaging is a promising technology for the production of accurate three-dimensional (3D images of submerged scenes. The main challenge is that radiation scattered off water gives rise to a disturbing signal (optical noise that degrades more and more the quality of 3D images for increasing turbidity. In this paper, we summarize a series of theoretical findings, that provide valuable hints for the development of experimental methods enabling a partial rejection of optical noise in underwater imaging systems. In order to assess the effectiveness of these methods, which range from modulation/demodulation to polarimetry, we carried out a series of experiments by using the laboratory prototype of an AM 3D imager (λ = 405 nm for marine archaeology surveys, in course of realization at the ENEA Artificial Vision Laboratory (Frascati, Rome. The obtained results confirm the validity of the proposed methods for optical noise rejection.

  6. Radar Range Sidelobe Reduction Using Adaptive Pulse Compression Technique

    Science.gov (United States)

    Li, Lihua; Coon, Michael; McLinden, Matthew

    2013-01-01

    technique could bring significant impact on future radar development. The novel feature of this innovation is the non-linear FM (NLFM) waveform design. The traditional linear FM has the limit (-20 log BT -3 dB) for achieving ultra-low-range sidelobe in pulse compression. For this study, a different combination of 20- or 40-microsecond chirp pulse width and 2- or 4-MHz chirp bandwidth was used. These are typical operational parameters for airborne or spaceborne weather radars. The NLFM waveform design was then implemented on a FPGA board to generate a real chirp signal, which was then sent to the radar transceiver simulator. The final results have shown significant improvement on sidelobe performance compared to that obtained using a traditional linear FM chirp.

  7. Bistatic radar

    CERN Document Server

    Willis, Nick

    2004-01-01

    Annotation his book is a major extension of a chapter on bistatic radar written by the author for the Radar Handbook, 2nd edition, edited by Merrill Skolnik. It provides a history of bistatic systems that points out to potential designers the applications that have worked and the dead-ends not worth pursuing. The text reviews the basic concepts and definitions, and explains the mathematical development of relationships, such as geometry, Ovals of Cassini, dynamic range, isorange and isodoppler contours, target doppler, and clutter doppler spread.Key Features * All development and analysis are

  8. 基于面阵探测器的凝视成像激光雷达%The Staring Imaging Laser Radar Based on Plane Array Detector

    Institute of Scientific and Technical Information of China (English)

    严惠民; 胡剑; 张秀达; 方毅; 王鹏鹏; 冯华君

    2013-01-01

      本文介绍了一种基于面阵探测器的凝视成像激光雷达系统。整个系统分为三部分,第一部分是脉冲激光发射系统,采用中心波长为808 nm 的半导体堆叠激光器作为光源;第二部分是接收系统,由成像物镜,像增强器和面阵探测器组成。第三部分是计算机图像数据采集处理系统。系统使用分时的两次测量法,先后用恒定增益和线性增益两种方式对接收到的光强进行调制,由这两次测量得到的光强信息解调出距离信息。文章分析了系统的噪声特性,对给定的系统参数用仿真软件估计了距离误差。实验表明,系统的实际距离分辨力和仿真分析得到的距离分辨力相符。%In order to quickly obtain the three-dimensional structural information of targets, a staring imaging laser radar system is developed. The system consists of three parts. The first part is that of light emission. The pulsed laser diode stack with center wavelength of 808 nm was used. The second part is the receiver which is made up of objective lens, image intensifier and CCD camera. The third part is that of image capture and processing. Two images with constant gain modulation and linear gain modulation were obtained in two measurements, and the distance information was demodulated. The error based on noise model was analyzed and estimated for given parameters. Some experiments were made and the results were consistent with theoretical analysis.

  9. Two-Dimensional Numerical Evaluation of 1-D Multi-FM SSD Experiments on OMEGA EP

    Science.gov (United States)

    Shvydky, A.; Hohenberger, M.; Marozas, J. A.; Bonino, M. J.; Canning, D.; Collins, T. J. B.; Kessler, T. J.; Kruschwitz, B. E.; McKenty, P. W.; Meyerhofer, D. D.; Sangster, T. C.; Zuegel, J. D.

    2013-10-01

    Adequate single-beam smoothing is crucial for successful direct-drive target implosions. One-dimensional, multi-FM smoothing by spectral dispersion (SSD) has been proposed to provide the required level of smoothing. A prototype multi-FM SSD system has been integrated into one beamline of the OMEGA EP Laser System and has been used in laser-driven planar-foil experiments to study the effectiveness of multi-FM SSD in reducing laser imprint. Recent experiments have achieved significantly improved signal-to-noise by employing a newly-qualified soft x-ray imaging diagnostic. Results of 2-D DRACO simulations will be compared with the available experimental data. The simulations include realistic time-dependent far-field spot intensity calculations that emulate the effect of the SSD and have a sufficiently fine computational mesh to resolve speckles. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  10. Listening to FM and Chasing Meteors

    Science.gov (United States)

    Nedeljkovic, Sasa; Barth Netterfield, C.

    2005-08-01

    This poster will show how a digital radio spectrometer working between 50 and 150 MHz can be used for meteor detection. The spectrometer is connected to a small wide-frequency, wide-beam antenna. With better than 50 kHz spectral resolution, the instrument can resolve individual FM radio and TV stations. Existing commercial transmitters over the horizon will be used as transmitters for the forward scattering method of meteor detection. Given the frequency, directivity, and power of transmitters, and time evolution of the reflection, we can extract dynamical parameters of the meteor using only one receiver.

  11. Radar detection

    CERN Document Server

    DiFranco, Julius

    2004-01-01

    This book presents a comprehensive tutorial exposition of radar detection using the methods and techniques of mathematical statistics. The material presented is as current and useful to today's engineers as when the book was first published by Prentice-Hall in 1968 and then republished by Artech House in 1980. The book is divided into six parts.

  12. Magnetoresistance and Anti-Ferromagnetic Coupling in FM-Graphene-FM Trilayers

    Science.gov (United States)

    Cobas, Enrique D.; van't Erve, Olaf M. J.; Cheng, Shu-Fan; Jonker, Berend T.

    Both high-magnetoresistance(MR) minority spin filtering and anti-ferromagnetic (AFM) coupling have been predicted for FM|Graphene|FM vertical heterostructures. Our previous experiments demonstrated ordinary magnetoresistance in NiFe-Graphene-Co heterostructures and no evident AFM coupling. Here we present experimental results that confirm both MR minority spin filtering and AFM coupling in high-quality FM|Graphene|FM heterostructures. The heterostructures were fabricated by a combination of sputtering, chemical vapor deposition and electron beam evaporation. The stack was patterned into symmetric cross-bar structures using Ar ion milling. Measurements show negative magnetoresistance in excess of 10 percent, confirming spin-filtering, and weak anti-ferromagnetic coupling throughout the temperature range 15K to 300K. The temperature dependence of the MR was studied and found consistent with thermal excitation of spin waves in the ferromagnetic electrodes. Junction resistance-area products are in the range of 10 Ωcm2. These heterostructures provide a fast and low-power magnetic field sensor in the sub-100 Oe range and are a step towards high-MR low RA-product MRAM junctions.

  13. The Use of Polysymptomatic Distress Categories in the Evaluation of Fibromyalgia (FM) and FM Severity

    NARCIS (Netherlands)

    Wolfe, Frederick; Walitt, Brian T.; Rasker, Hans; Katz, Robert S.; Häuser, Winfried

    2015-01-01

    Objective The polysymptomatic distress (PSD) scale is derived from variables used in the 2010 American College of Rheumatology (ACR) fibromyalgia (FM) criteria modified for survey and clinical research. The scale is useful in measuring the effect of PSD over the full range of pain-related clinical s

  14. The Use of Polysymptomatic Distress Categories in the Evaluation of Fibromyalgia (FM) and FM Severity

    NARCIS (Netherlands)

    Wolfe, Frederick; Walitt, Brian T.; Rasker, Hans J.; Katz, Robert S.; Häuser, Winfried

    2015-01-01

    Objective The polysymptomatic distress (PSD) scale is derived from variables used in the 2010 American College of Rheumatology (ACR) fibromyalgia (FM) criteria modified for survey and clinical research. The scale is useful in measuring the effect of PSD over the full range of pain-related clinical

  15. Multiple mechanisms shape FM sweep rate selectivity: complementary or redundant?

    Directory of Open Access Journals (Sweden)

    Zoltan M Fuzessery

    2012-08-01

    Full Text Available Auditory neurons in the inferior colliculus (IC of the pallid bat have strong rate selective responses to downward frequency modulated (FM sweeps attributable to the spectrotemporal pattern of their echolocation call (a brief FM pulse. Several mechanisms are known to shape FM rate selectivity within the pallid bat IC. Here we explore how two mechanisms, stimulus duration and high-frequency inhibition (HFI, can interact to shape FM rate selectivity within the same neuron. Results from extracellular recordings indicated that a derived duration-rate function (based on tonal response was highly predictive of the shape of the FM rate response. Longpass duration selectivity for tones was predictive of slowpass rate selectivity for FM sweeps, both of which required long stimulus durations and remained intact following iontophoretic blockade of inhibitory input. Bandpass duration selectivity for tones, sensitive to only a narrow range of tone durations, was predictive of bandpass rate selectivity for FM sweeps. Conversion of the tone duration response from bandpass to longpass after blocking inhibition was coincident with a change in FM rate selectivity from bandpass to slowpass indicating an active inhibitory component to the formation of bandpass selectivity. Independent of the effect of duration tuning on FM rate selectivity, the presence of HFI acted as a fastpass FM rate filter by suppressing slow FM sweep rates. In cases where both mechanisms were present, both had to be eliminated, by removing inhibition, before bandpass FM rate selectivity was affected. It is unknown why the auditory system utilizes multiple mechanisms capable of shaping identical forms of FM rate selectivity though it may represent distinct but convergent modes of neural signaling directed at shaping response selectivity for important biologically relevant sounds.

  16. Measurements of Partial Reflections at 3.18 Mhz Using the CW Radar Technique

    Science.gov (United States)

    Priese, J.; Singer, W.

    1984-01-01

    An equipment for measuring partial reflections using the FM-CW-radar principle at 3.18 MHz, installed at the Ionospheric Observatory Juliusruh of the CISTP (HHI), is described. The linear FM-chirp of 325 kHz bandwidth is Gaussian-weighted in amplitude and gives a height resolution of 1.5 km (chirp length is 0.6 sec). Preliminary results are presented for the first observation period in winter 1982/83.

  17. Limitations of Radar Coordinates

    OpenAIRE

    Bini, Donato; Lusanna, Luca; Mashhoon, Bahram

    2004-01-01

    The construction of a radar coordinate system about the world line of an observer is discussed. Radar coordinates for a hyperbolic observer as well as a uniformly rotating observer are described in detail. The utility of the notion of radar distance and the admissibility of radar coordinates are investigated. Our results provide a critical assessment of the physical significance of radar coordinates.

  18. Superfluid dynamics of 258Fm fission

    CERN Document Server

    Scamps, Guillaume; Lacroix, Denis

    2015-01-01

    Theoretical description of nuclear fission remains one of the major challenges of quantum many-body dynamics. The slow, mostly adiabatic motion through the fission barrier is followed by a fast, non-adiabatic descent of the potential between the fragments. The latter stage is essentially unexplored. However, it is crucial as it generates most of the excitation energy in the fragments. The superfluid dynamics in the latter stage of fission is obtained with the time-dependent Hartree-Fock theory including BCS dynamical pairing correlations. The fission modes of the 258Fm nucleus are studied. The resulting fission fragment characteristics show a good agreement with experimental data. Quantum shell effects are shown to play a crucial role in the dynamics and formation of the fragments. The importance of quantum fluctuations beyond the independent particle/quasi-particle picture is underlined and qualitatively studied.

  19. Resarch on the Future of FM in the Nordic Countries

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Rasmussen, Birgitte; Andersen, Per Dannemand

    2012-01-01

    that the strategy reflects future needs and expectations among Nordic researchers and practitioners within the FM field. The foresight process included four elements: The first element was a preliminary survey of existing studies and foresight projects on the future for FM. In particular the survey included...... in the FM sector. As a third element the preliminary results of the foresight project were presented and discussed at a Nordic workshop as part of a Nordic FM conference arranged by CFM at DTU in August 2011. The fourth element was a Nordic Delphi-like questionnaire with the aim of identifying and ranking...

  20. Performance analysis for laser radars based on Geiger-mode APD%基于Geiger-mode APD的激光雷达性能分析

    Institute of Scientific and Technical Information of China (English)

    方照勋; 张华; 李海廷; 路英宾; 高剑波; 陈德章; 卿光弼

    2011-01-01

    针对基于盖革模式雪崩光电二极管(Gm-APD)阵列的激光雷达,提出一种分析其探测性能的方法.以分析单个Gm-APD像元产生的初始光电子和暗计数噪声为基础,对Gm-APD像元的探测概率、虚警概率和漏警概率进行研究,并进一步提出一种多脉冲阚值探测法,并对其探测概率、虚警概率进行了研究和仿真.结果表明,对2~10 km外的目标,采用128×128像元面阵探测器,单脉冲能量小于200 mJ时,探测概率随脉冲能量提高而提高;单脉冲能量大干200 mJ时,探测概率保持不变;当采用多脉冲阈值探测、信号较弱时,探测概率总是随脉冲能量提高而提高,虚警概率总是随脉冲能量提高而降低.%This paper introduces a method for analyzing the performance of laser radar based on Geiger-mode avalanche photodiode(APD) array. The detection probability, false-alarm probability and miss alarm probability are researched by analyzing the creation of primary photon electronics and dark count rate noise. Further more,the method of threshold detection with multiple-pulses are proposed, of which the detection probability and false probability are researched and simulated. For a target at a distance of 2 km to 10 km and the 128 x 128 Geiger-mode APD array, the detection probability of the ladar system can be improved as the pulse energy increasing, while the pulse energy should less than 200 mJ. When the pulse energy is above 200 mj,the detection probability is constant. For the threshold detection with multiple-pulses,the detection probability of the ladar system can be improved as the pulse energy increasing, and the false-alarm probability can be reduced as the pulse energy increasing.

  1. Control System of Unstacking Robot by Image-Based Modeling Using Laser Radar%基于激光雷达三维图像建模的机器人拆码垛控制系统

    Institute of Scientific and Technical Information of China (English)

    魏志强; 李兵; 屈玉丰; 沙群

    2013-01-01

    为满足智能化仓储系统对高速自动拆码垛系统的实际需求,给出一种基于激光雷达的机器人拆码垛控制系统,由激光雷达扫描构建周转箱的三维图像,通过建立相应的坐标系统及目标识别算法,计算出周转箱的中心位置坐标和偏转角等信息,并将信息传输给机器人,从而实现机器人拆垛操作.实际应用表明,系统运行稳定可靠,实现了预期的设计目标.%In order to meet the actual requirement for high - speed automatic unstacking and palletizing in intelligent warehouse system, a control system for unstacking robot based on laser radar is given. The three - dimensional image of the containers is established from laser radar scanning data,and the information of center position and the deflection angle of the containers is obtained by target recognition based on the established coordinates. The data information is then sent to the robot , and so the automatic unstacking operation is realized. Actual testing results indicate that the system is stable and reliable. The goal of anticipated design is achieved.

  2. RADAR PPI Scope Overlay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — RADAR PPI Scope Overlays are used to position a RADAR image over a station at the correct resolution. The archive maintains several different RADAR resolution types,...

  3. Advances in bistatic radar

    CERN Document Server

    Willis, Nick

    2007-01-01

    Advances in Bistatic Radar updates and extends bistatic and multistatic radar developments since publication of Willis' Bistatic Radar in 1991. New and recently declassified military applications are documented. Civil applications are detailed including commercial and scientific systems. Leading radar engineers provide expertise to each of these applications. Advances in Bistatic Radar consists of two major sections: Bistatic/Multistatic Radar Systems and Bistatic Clutter and Signal Processing. Starting with a history update, the first section documents the early and now declassified military

  4. Lasers '92; Proceedings of the International Conference on Lasers and Applications, 15th, Houston, TX, Dec. 7-10, 1992

    Science.gov (United States)

    Wang, Charles P. (Editor)

    1993-01-01

    Papers from the conference are presented, and the topics covered include the following: x-ray lasers, excimer lasers, chemical lasers, high power lasers, blue-green lasers, dye lasers, solid state lasers, semiconductor lasers, gas and discharge lasers, carbon dioxide lasers, ultrafast phenomena, nonlinear optics, quantum optics, dynamic gratings and wave mixing, laser radar, lasers in medicine, optical filters and laser communication, optical techniques and instruments, laser material interaction, and industrial and manufacturing applications.

  5. Reflecting on future research concerning the added value of FM

    DEFF Research Database (Denmark)

    Jensen, Per Anker; van der Voordt, Theo; Coenen, Christian

    2014-01-01

    . There is a need for a better understanding of alignment between FM and core business, performance measurement methods and how models such as the FM Value Map can be of value to the involved stakeholders. Corporate social responsibility (CSR), sustainability and branding have great potential to add value...

  6. 75 FR 43897 - FM TABLE OF ALLOTMENTS, GRANTS PASS, OREGON

    Science.gov (United States)

    2010-07-27

    ... COMMISSION 47 CFR Part 73 FM TABLE OF ALLOTMENTS, GRANTS PASS, OREGON AGENCY: Federal Communications... the allotment of FM Channel 257A as the second commercial allotment at Grants Pass, Oregon. The channel can be allotted at Grants Pass in compliance with the Commission's minimum distance...

  7. Preparing Students to Take SOA/CAS Exam FM/2

    Science.gov (United States)

    Marchand, Richard J.

    2014-01-01

    This paper provides suggestions for preparing students to take the actuarial examination on financial mathematics, SOA/CAS Exam FM/2. It is based on current practices employed at Slippery Rock University, a small public liberal arts university. Detailed descriptions of our Theory of Interest course and subsequent Exam FM/2 prep course are provided…

  8. Towards sustainable public FM: collective building of capabilities

    DEFF Research Database (Denmark)

    Ramskov Galamba, Kirsten; Nielsen, Susanne Balslev

    2016-01-01

    Purpose Public facilities management (FM) is in the unique position of aligning building projects and FM with the policies of sustainable development at societal level. However, sustainable facilities management (SFM) is an emergent profession, and there is a need to build a code of conduct for S...

  9. 47 CFR 73.4017 - Application processing: Commercial FM stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Application processing: Commercial FM stations... RADIO SERVICES RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.4017 Application processing: Commercial FM stations. See Report and Order, MM Docket 84-750, FCC 85-125, adopted March 4,...

  10. FM: Clinically Meaningful Rorschach Index with Minority Children?

    Science.gov (United States)

    Scott, Ralph

    1981-01-01

    Uses a case vignette to consider the possibility that the Rorschach FM index may be a forerunner of abstract thinking. Data support the major finding that FM may enable educational diagnosticians to more accurately estimate the intellectual capabilities of some preschool minority and other culturally disadvantaged children. (Author/JAC)

  11. 47 CFR 73.316 - FM antenna systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM antenna systems. 73.316 Section 73.316... Broadcast Stations § 73.316 FM antenna systems. (a) It shall be standard to employ horizontal polarization...) Directional antennas. A directional antenna is an antenna that is designed or altered for the purpose...

  12. 47 CFR 73.597 - FM stereophonic sound broadcasting.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM stereophonic sound broadcasting. 73.597 Section 73.597 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES... broadcasting. A noncommercial educational FM broadcast station may, without specific authority from the...

  13. 一种用于FM-FM遥测系统的测试信号源%A Kind of Testing Signal Generator for FM-FM Telemetry System

    Institute of Scientific and Technical Information of China (English)

    孙进平; 蓝天; 程吉宽

    2000-01-01

    介绍一种满足IRIG标准的FM-FM调频信号源.根据试验结果,证明这种信号源不仅性能稳定,而且具有很好的灵活性.在各类符合IRIG标准FM-FM体制遥测接收机的研制中具有一定的实用价值.

  14. Research of beam conditioning technologies using continuous phase plate, Multi-FM smoothing by spectral dispersion and polarization smoothing

    Science.gov (United States)

    Zhang, Rui; Jia, Huaiting; Tian, Xiaocheng; Yuan, Haoyu; Zhu, Na; Su, Jingqin; Hu, Dongxia; Zhu, Qihua; Zheng, Wanguo

    2016-10-01

    In the research of inertial confinement fusion, laser plasma interaction (LPI) is becoming a key problem that affects ignition. Here, multi-frequency modulation (Multi-FM) smoothing by spectral dispersion (SSD), continuous phase plate (CPP) and polarization smoothing (PS) were experimentally studied and implemented on the SG-III laser facility. After using these techniques, the far field distribution of SG-Ⅲ laser facility can be adjusted, controlled and repeated accurately. The output spectrums of the cascade phase modulators used for Multi-FM SSD were stable and the FM-to-AM effect can be restrained. Experiments on SG-III laser facility indicate that when the number of color cycles adopts 1, imposing SSD with 3.3 times diffraction limit (TDL) did not lead to pinhole closure in the spatial filters of preamplifier and main amplifiers with 30-TDL pinhole size. The nonuniformity of the focal spots using Multi-FM SSD, CPP and PS drops to 0.18, comparing to 0.26 with CPP+SSD, 0.57 with CPP+PS and 0.84 with only CPP and wedged lens. Polarization smoothing using flat birefringent plate in the convergent beam of final optics assembly (FOA) was studied. The PS plates were manufactured and equipped on SG-III laser facility for LPI research. Combined beam smoothing and polarization manipulation were also studied to solve the LPI problem. Results indicate that through adjusting dispersion directions of SSD beams in a quad, two dimensional SSD can be obtained. Using polarization control plate (PCP), polarization on the near field and far field can be manipulated, providing new method to solve LPI problem in indirect drive laser fusion.

  15. Decay study of {sup 246}Fm at SHIP

    Energy Technology Data Exchange (ETDEWEB)

    Venhart, M. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Slovak Academy of Sciences, Institute of Physics, Bratislava (Slovakia); Hessberger, F.P.; Ackermann, D.; Heinz, S.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Antalic, S.; Saro, S. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Gray-Jones, C.; Herzberg, R.D.; Papadakis, P. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Greenlees, P.T.; Ketelhut, S.; Leino, M. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt am Main (Germany); Rostron, D. [Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt am Main (Germany); Rudolph, D. [Lund University, Department of Physics, Lund (Sweden); Sulignano, B. [CEA Saclay, DAPNIA/SPhN, Gif/Yvette Cedex (France)

    2011-02-15

    The decay chain of {sup 246}Fm has been investigated employing the SHIP separator at GSI Darmstadt. The {sup 246}Fm nuclei were produced via the {sup 40}Ar({sup 208}Pb, 2n){sup 246}Fm fusion-evaporation reaction. Improved values of the half-life, T{sub 1/2} = 1.54(4) s, and of the spontaneous fission branching ratio, b{sub SF} = 0.068(6), of {sup 246}Fm were obtained. The {beta}{sup +} /electron capture branching ratio, b{sub EC} = 0.39(3), of {sup 242}Cf was deduced. Possible structures of high-K states in {sup 246}Fm are discussed within the framework of a model calculation based on the Woods-Saxon potential. (orig.)

  16. Note from TS/FM Group

    CERN Multimedia

    2007-01-01

    Renovation work at Restaurant no. 1 Please note that starting from 5 March and for one week, the men's toilets in Bldg. 500 (underground) will be closed because of the renovation work at Restaurant No. 1. The women's toilets in the same place will exceptionally be open to men and women during the same period. We apologize for the inconvenience and we are at your disposal for further information. Shuttle requests Please note that starting from 1 March 2007, shuttle requests: for official visits or bidders' conferences on the CERN site; to/from the airport or the centre of Geneva; for long distances, must be made via Fm.Support@cern.ch or by calling 77777. The radio taxi will still be reachable on 76969. Please note that starting from 1st of March, requests for the transport of PCs from your office to the PC store (Bldg. 513) and vice-versa, must be made the 'transport request' form on EDH under the field 'removals'). Mail distribution Please note that starting from 1 March 2007, mail distrib...

  17. Radar-to-Radar Interference Suppression for Distributed Radar Sensor Networks

    OpenAIRE

    Wen-Qin Wang; Huaizong Shao

    2014-01-01

    Radar sensor networks, including bi- and multi-static radars, provide several operational advantages, like reduced vulnerability, good system flexibility and an increased radar cross-section. However, radar-to-radar interference suppression is a major problem in distributed radar sensor networks. In this paper, we present a cross-matched filtering-based radar-to-radar interference suppression algorithm. This algorithm first uses an iterative filtering algorithm to suppress the radar-to-radar ...

  18. Eastward traverse of equatorial plasma plumes observed with the Equatorial Atmosphere Radar in Indonesia

    OpenAIRE

    S. Fukao; Yokoyama, T.; Tayama, T.; Yamamoto, M.; Maruyama, T.; Saito, S.

    2006-01-01

    The zonal structure of radar backscatter plumes associated with Equatorial Spread F (ESF), probably modulated by atmospheric gravity waves, has been investigated with the Equatorial Atmosphere Radar (EAR) in West Sumatra, Indonesia (0.20° S, 100.32° E; dip latitude 10.1° S) and the FM-CW ionospheric sounders on the same magnetic meridian as the EAR. The occurrence locations and zonal distances of the ESF plumes were determined with multi-beam obs...

  19. How to Create and Manipulate Radar Range-Doppler Plots

    Science.gov (United States)

    2014-12-01

    set of wave fronts with constant wavelength, direction, and relative phase. Electromagnetic waves produced by radar transmitters and lasers are... radars . The Matlab function fft orders its DFT amplitudes in a way that renders negative frequencies positive and greater than the Nyquist frequency. I...UNCLASSIFIED How to Create and Manipulate Radar Range–Doppler Plots Don Koks Cyber & Electronic Warfare Division Defence Science and Technology

  20. Ground penetrating radar and terrestrial laser scanner surveys on deposits of dilute pyroclastic density current deposits: insights for dune bedform genesis

    Science.gov (United States)

    Rémi Dujardin, Jean; Amin Douillet, Guilhem; Abolghasem, Amir; Cordonnier, Benoit; Kueppers, Ulrich; Bano, Maksim; Dingwell, Donald B.

    2014-05-01

    Dune bedforms formed by dilute pyroclastic density currents (PDC) are often described or interpreted as antidunes and chute and pools. However, the interpretation remains essentially speculative and is not well understood. This is largely due to the seeming impossibility of in-situ measurements and experimental scaling, as well as the lack of recent, 3D exposures. Indeed, most dune bedform cross-stratifications from the dilute PDC record outcrop in 2D sections. The 2006 eruption of Tungurahua has produced well-developed bedforms that are well-exposed on the surface of the deposits with easy access. We performed a survey of these deposits combining ground penetrating radar (GPR) profiling with terrestrial laser scanning of the surface. The GPR survey was carried in dense arrays (from 10 to 25 cm spacing between profiles) over ca. 10 m long bedforms. GPR profiles were corrected for topography from photogrammetry data. An in-house software, RadLab (written in matlab), was used for common processing of individual profiles and 2D & 3D topographic migration. Each topography-corrected profile was then loaded into a seismic interpretation software, OpenDtect, for 3D visualization and interpretation. Most bedforms show high lateral stability that is independent of the cross-stratification pattern (that varies between stoss-aggrading bedsets, stoss-erosive bedsets and stoss-depositional lensoidal layers). Anecdotic bedforms have their profiles that evolve laterally (i.e. in a direction perpendicular to the flow direction). Cannibalization of two dune bedforms into a single one on one end of the profile can evolve into growth of a single bedform at the other lateral end. Also, lateral variation in the migration direction occurs, i.e. a single bedform can show upstream aggradation at one lateral end of the bedform, but show downstream migration at the other end. Some bedforms have great variations in their internal structure. Several episodes of growth and erosion can be

  1. Analysis of FM demodulator output noise with applications to FM telemetry

    Directory of Open Access Journals (Sweden)

    Rajendra Kumar

    2006-07-01

    Full Text Available We present an analysis for evaluating the probability density function (pdf of the noise at the output of the frequency demodulator. It is shown that the noise is non-Gaussian and that for low to medium signal-to-noise power ratios, its pdf differs very significantly from the Gaussian pdf commonly assumed in simplified analysis. These results are very important for analyzing the performance of the PCM/FM type of modulation schemes used in telemetry systems as illustrated in the paper.

  2. ANSI / FM Approvals 2510 flood abatement equipment test standard

    Directory of Open Access Journals (Sweden)

    Kravetz Frédéric

    2016-01-01

    Full Text Available Natural hazards, including flooding, continue to be the leading cause of commercial and industrial property damage worldwide. Until recently, there has been a limited amount of readily available guidance on choosing flood abatement protection. FM Approvals, a division of FM Global, one of the world’s largest business property insurers, working together with the Association of State Floodplain Managers and the US Army Corps of Engineers have developed a National Flood Barrier Test Program after recognizing the urgent demand for reliable flood abatement products to mitigate potential losses. This lead to the ANSI/ FM2510 flood abatement equipment standard.

  3. Construct irreducible representations of quantum groups Uq(fm(K))

    Institute of Scientific and Technical Information of China (English)

    Xin TANG

    2008-01-01

    In this paper,we construct families of irreducible representations for a class of quantum groups Uq(fm(K)).First,we give a natural construction of irreducible weight representations for Uq(fm(K)) using methods in spectral theory developed by Rosenberg.Second,we study the Whittaker model for the center of Uq(fm(K)).As a result,the structure of Whittaker representations is determined,and all irreducible Whittaker representations are explicitly constructed.Finally,we prove that the annihilator of a Whittaker representation is centrally generated.

  4. Role of spin polarization in FM/Al/FM trilayer film at low temperature

    Science.gov (United States)

    Lu, Ning; Webb, Richard

    2014-03-01

    Measurements of electronic transport in diffusive FM/normal metal/FM trilayer film are performed at temperature ranging from 2K to 300K to determine the behavior of the spin polarized current in normal metal under the influence of quantum phase coherence and spin-orbital interaction. Ten samples of Hall bar with length of 200 micron and width of 20 micron are fabricated through e-beam lithography followed by e-gun evaporation of Ni0.8Fe0.2, aluminum and Ni0.8Fe0.2 with different thickness (5nm to 45nm) in vacuum. At low temperature of 4.2K, coherent backscattering, Rashba spin-orbital interaction and spin flip scattering of conduction electrons contribute to magnetoresistance at low field. Quantitative analysis of magnetoresistance shows transition between weak localization and weak anti-localization for samples with different thickness ratio, which indicates the spin polarization actually affects the phase coherence length and spin-orbital scattering length. However, at temperature between 50K and 300K, only the spin polarization dominates the magnetoresistance.

  5. Sniper bullet detection by millimeter-wave radar

    Science.gov (United States)

    Bernstein, Uri; Lefevre, Russell J.; Mann, John; Avent, Randy K.; Deo, Naresh

    1999-01-01

    Law enforcement and military operations would clearly benefit from a capability to locate snipers by backtracking the sniper's bullet trajectory. Achieving sufficient backtracking accuracy for bullets is a demanding radar design, requiring good measurement accuracy, high update rate, and detection of very low cross-section objects. In addition, reasonable cost is a driving requirement for law enforcement use. These divergent design requirements are addressed in an experimental millimeter-wave focal plane array radar that uses integrated millimeter-wave receiver technology. The radar is being built for DARPA by Technology Service Corporation, with assistance from M.I.T. Lincoln Laboratory and QuinStar Technology. The key element in the radar is a 35-GHz focal plane array receiver. The receiving antenna lens focuses radar signals from a wide field of view onto an array of receivers, each receiver processing a separate element of the field of view. Receiver detections are then combined in a tracking processor. An FM-CW waveform is used to provide high average power, good range resolution, and stationary clutter rejection. TSC will be testing the sniper detection radar, using radar environment simulator technology developed at Lincoln Laboratory. The simulator will retransmit the received signal with the range delay, Doppler shift, and ERP for various simulated bullet trajectories.

  6. Horizontal Branch stars as AmFm/HgMn stars

    CERN Document Server

    Michaud, G

    2008-01-01

    Recent observations and models for horizontal branch stars are briefly described and compared to models for AmFm stars. The limitations of those models are emphasized by a comparison to observations and models for HgMn stars.

  7. Comparisons between PW Doppler system and enhanced FM Doppler system

    DEFF Research Database (Denmark)

    Wilhjelm, Jens E.; Pedersen, P. C.

    1995-01-01

    This paper presents a new implementation of an echo-ranging FM Doppler system with improved performance, relative to the FM Doppler system reported previously. The use of long sweeps provides a significant reduction in peak to average power ratio compared to pulsed wave (PW) emission. A PW Doppler...... system exploits the direct relationship between arrival time of the received signal and range from the transducer. In the FM Doppler systems, a similar relationship exists in the spectral domain of the demodulated received signals, so that range is represented by frequency. Thus, a shift in location...... of moving scatterers between consecutive emissions corresponds to a frequency shift in the spectral signature. The improvement relative to the earlier version of the FM Doppler system is attained by utilizing cross-correlation of real spectra rather than of magnitude spectra for assessing flow velocity...

  8. Risk Management from Corporate and FM Perspectives: Two case studies

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: To investigate how Risk Management (RM) is perceived and practiced in Facilities Management (FM) and corporate management and to evaluate the potential benefits of an increased application. Theory: RM is a generic management discipline, but apparently it has not achieved the attention...... it deserves in FM. Application of RM in FM could help to increase the strategic importance and awareness of FM among corporate managers. Approach: A preliminary study with expert interviews was initially conducted followed by a main study with an interview survey in two Danish case companies - a real estate...... company and a consulting engineering company. Findings: The research showed that RM was applied in both companies to a higher degree than initially expected, but often using other terminology. The real estate company had a much stronger focus on RM in relation to the technical aspects of real estate...

  9. The new real-time measurement capabilities of the profiling TARA radar

    NARCIS (Netherlands)

    Unal, C.M.H.; Dufournet, Y.; Otto, T.; Russchenberg, H.W.J.

    2012-01-01

    In the past 10 years, the S-band FM-CW TARA (Transportable Atmospheric RAdar), placed at the Cabauw Experimental Site for Atmospheric Research (CESAR), provided in real-time vertical profiles of the Doppler moments. Classical spectral processing was carried out. The polarimetric and multi-beam measu

  10. 激光雷达散射截面的比对测量法及其精度检测%Relative measurement of laser radar cross section and its accuracy test

    Institute of Scientific and Technical Information of China (English)

    曲卫东; 杜自强; 薛建国; 薛挺; 王娟锋

    2011-01-01

    The relative measurement is commonly used in measurement of laser radar cross section (LRCS) of a field target. It is effected by some factors, such as light beam mode of laser in measuring system, stability of laser power, atmospheric absorption, scattering and turbulence, laser reflection of background, circuit noise, etc. Laser beam mode is most important in these factors, causing the accuracy of LRCS measurement hard to test objectively. In order to solve this problem, the relative measurement of LRCS and its test system were introduced firstly. Then the effect of laser beam mode on system accuracy was discussed. Finally, the test method of system accuracy that combined shadowing method by using extinction cloth and laser spot image analyzing method was introduced. In addition, how to reduce the effect of light beam mode on system accuracy was analyzed.%野外目标激光雷达散射截面(LRCS)的测量通常使用比对测量方法.该方法受到测量系统激光光束模式,激光功率稳定性,大气吸收、散射和湍流,背景的激光漫反射回波,系统探测电路噪声等因素的影响.其中,测量系统激光光束模式是最重要的影响因素,造成了比对测量方法中LRCS测量精度难以客观、全面检测的问题.因此,在介绍LRCS的比对测量法及测试系统的基础上,分析了光束模式对系统LRCS测量精度的影响,提出了消光布遮蔽法和光斑分析法相结合的系统LRCS测量精度检测方法.最后,对实际应用中如何减小光斑模式的影响以提高系统LRCS测量精度进行了分析.

  11. Ambiguity Function Analysis and Processing for Passive Radar Based on CDR Digital Audio Broadcasting

    Directory of Open Access Journals (Sweden)

    Zhang Qiang

    2015-01-01

    Full Text Available China Digital Radio (CDR broadcasting is a new standard of digital audio broadcasting of FM frequency (87–108 MHz based on our research and development efforts. It is compatible with the frequency spectrum in analog FM radio and satisfies the requirements for smooth transition from analog to digital signal in FM broadcasting in China. This paper focuses on the signal characteristics and processing methods of radio-based passive radar. The signal characteristics and ambiguity function of a passive radar illumination source are analyzed. The adverse effects on the target detection of the side peaks owing to cyclic prefix, the Doppler ambiguity strips because of signal synchronization, and the range of side peaks resulting from the signal discontinuous spectrum are then studied. Finally, methods for suppressing these side peaks are proposed and their effectiveness is verified by simulations.

  12. Adaptive radar resource management

    CERN Document Server

    Moo, Peter

    2015-01-01

    Radar Resource Management (RRM) is vital for optimizing the performance of modern phased array radars, which are the primary sensor for aircraft, ships, and land platforms. Adaptive Radar Resource Management gives an introduction to radar resource management (RRM), presenting a clear overview of different approaches and techniques, making it very suitable for radar practitioners and researchers in industry and universities. Coverage includes: RRM's role in optimizing the performance of modern phased array radars The advantages of adaptivity in implementing RRMThe role that modelling and

  13. Radar and ARPA manual

    CERN Document Server

    Bole, A G

    2013-01-01

    Radar and ARPA Manual focuses on the theoretical and practical aspects of electronic navigation. The manual first discusses basic radar principles, including principles of range and bearing measurements and picture orientation and presentation. The text then looks at the operational principles of radar systems. Function of units; aerial, receiver, and display principles; transmitter principles; and sitting of units on board ships are discussed. The book also describes target detection, Automatic Radar Plotting Aids (ARPA), and operational controls of radar systems, and then discusses radar plo

  14. Clear-air radar observations of the atmospheric boundary layer

    Science.gov (United States)

    Ince, Turker

    2001-10-01

    This dissertation presents the design and operation of a high-resolution frequency-modulated continuous-wave (FM- CW) radar system to study the structure and dynamics of clear-air turbulence in the atmospheric boundary layer (ABL). This sensitive radar can image the vertical structure of the ABL with both high spatial and temporal resolutions, and provide both qualitative information about the morphology of clear-air structures and quantitative information on the intensity of fluctuations in refractive-index of air. The principles of operation and the hardware and data acquisition characteristics of the radar are described in the dissertation. In October 1999, the radar participated in the Cooperative Atmosphere-Surface Exchange Study (CASES'99) Experiment to characterize the temporal structure and evolution of the boundary-layer features in both convective and stable conditions. The observed structures include clear-air convection, boundary layer evolution, gravity waves, Kelvin-Helmholtz instabilities, stably stratified layers, and clear-air turbulence. Many of the S-band radar images also show high- reflectivity returns from Rayleigh scatterers such as insects. An adaptive median filtering technique based on local statistics has, therefore, been developed to discriminate between Bragg and Rayleigh scattering in clear-air radar observations. The filter is tested on radar observations of clear air convection with comparison to two commonly used image processing techniques. The dissertation also examines the statistical mean of the radar-measured C2n for clear-air convection, and compares it with the theoretical predictions. The study also shows that the inversion height, local thickness of the inversion layer, and the height of the elevated atmospheric layers can be estimated from the radar reflectivity measurements. In addition, comparisons to the radiosonde-based height estimates are made. To examine the temporal and spatial structure of C2n , the dissertation

  15. Amplitude-stabilized frequency-modulated laser diode and its interferometric sensing applications.

    Science.gov (United States)

    Takahashi, Y; Yoshino, T; Ohde, N

    1997-08-20

    A direct frequency-modulated (FM) laser diode light source without light power variation is developed. The amplitude variation of the FM laser diode is compensated by means of a feedback system with use of a superluminescent diode as an external light power controller. Output power greater than 1 mW is obtained at the modulation frequency to 5 kHz with a >10 stabilization factor. By use of the amplitude-stabilized FM laser diode, we measured subfringes with high accuracy in FM continuous wave interferometry, increased the dynamic range of the displacement measurement, and improved the stabilization factor in the laser diode feedback interferometer.

  16. 激光雷达技术在河南栾川县山洪灾害调查中的示范应用%Application of laser radar technique in flash flood disaster investigation in Luanchuan County

    Institute of Scientific and Technical Information of China (English)

    张琦建; 刘昌军; 唐学哲; 孙涛; 郭良

    2015-01-01

    In recent years, the airborne Lidar is widely applied due to its ability to quickly obtain the third degree ground terrain information with efficiency and accuracy. Using UAV laser radar measurement technique, this research acquired flash flood data in two typical smal watersheds of Luanchuan County and introduced the process of the technique. Considering requirements of flash flood disaster evaluations, this paper detailed various methods including classification of laser point cloud data, DEM production, data processing technique of river cross-sections, and key technology of the automatic extraction of houses location and elevation. UAV laser radar technology features rapid data acquisition speed and high precision; it can meet the requirements of flash flood disaster investigations and provides the application demonstration of this technology. Consequently, this technique wil play an important role in investigation of flash flood disasters and have great application prospect.%机载LiDAR技术获取地面三维地物信息快捷、高效,近年来发展迅速,应用广泛。介绍了无人机雷达技术的航测技术流程,结合山洪灾害调查评价的应用需求,论述了激光点云数据的分类方法,数字高程模型(DEM)制作方法,河道断面批处理方法,居民户位置和高程的自动提取方法等应用关键技术,并以栾川县2个山洪灾害典型小流域为例,开展了示范应用。研究表明,无人机激光雷达测量技术获取数据速度快、精度高,能够满足山洪灾害调查的工作要求,为全国无资料地区山洪灾害调查工作提供了新技术的应用示范,将在全国山洪灾害调查工作中发挥巨大作用,具有较大的应用前景。

  17. Principles of modern radar systems

    CERN Document Server

    Carpentier, Michel H

    1988-01-01

    Introduction to random functions ; signal and noise : the ideal receiver ; performance of radar systems equipped with ideal receivers ; analysis of the operating principles of some types of radar ; behavior of real targets, fluctuation of targets ; angle measurement using radar ; data processing of radar information, radar coverage ; applications to electronic scanning antennas to radar ; introduction to Hilbert spaces.

  18. Passive MIMO Radar Detection

    Science.gov (United States)

    2013-09-01

    cumulative distribution function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 CORA COvert RAdar...PaRaDe), developed by the Insti- tute of Electronic Systems at the Warsaw University of Technology [59, 60]; COvert RAdar ( CORA ), developed by the German

  19. Weather Radar Impact Zones

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent an inventory of the national impacts of wind turbine interference with NEXRAD radar stations. This inventory was developed by the NOAA Radar...

  20. Digital LPI Radar Detector

    OpenAIRE

    Ong, Peng Ghee; Teng, Haw Kiad

    2001-01-01

    Approved for public release; distribution is unlimited The function of a Low Probability ofIntercept (LPI) radar is to prevent its interception by an Electronic Support (ES) receiver. This objective is generally achieved through the use of a radar waveform that is mismatched to those waveforms for which an ES receiver is tuned. This allows the radar to achieve a processing gain, with respect to the ES receiver, that is equal to the time-bandwidth product ofthe radar waveform. This...

  1. Network radar countermeasure systems integrating radar and radar countermeasures

    CERN Document Server

    Jiang, Qiuxi

    2016-01-01

    This is the very first book to present the network radar countermeasure system. It explains in detail the systematic concept of combining radar and radar countermeasures from the perspective of the information acquisition of target location, the optimization of the reconnaissance and detection, the integrated attack of the signals and facilities, and technological and legal developments concerning the networked system. It achieves the integration of the initiative and passivity, detection and jamming. The book explains how the system locates targets, completes target identification, tracks targets and compiles the data.

  2. Deep Stochastic Radar Models

    OpenAIRE

    Wheeler, Tim Allan; Holder, Martin; Winner, Hermann; Kochenderfer, Mykel

    2017-01-01

    Accurate simulation and validation of advanced driver assistance systems requires accurate sensor models. Modeling automotive radar is complicated by effects such as multipath reflections, interference, reflective surfaces, discrete cells, and attenuation. Detailed radar simulations based on physical principles exist but are computationally intractable for realistic automotive scenes. This paper describes a methodology for the construction of stochastic automotive radar models based on deep l...

  3. Radar: Human Safety Net

    Science.gov (United States)

    Ritz, John M.

    2016-01-01

    Radar is a technology that can be used to detect distant objects not visible to the human eye. A predecessor of radar, called the telemobiloscope, was first used to detect ships in the fog in 1904 off the German coast. Many scientists have worked on the development and refinement of radar (Hertz with electromagnetic waves; Popov with determining…

  4. Analysis of Coexistence of DRM Plus and FM Broadcasting Systems

    Directory of Open Access Journals (Sweden)

    K. Ulovec

    2015-12-01

    Full Text Available This paper deals with DRM (Digital Radio Mondiale Plus and FM (Frequency Modulation radio broadcasting systems coexistence. It brings results based on measurement of mutual interferences of each to other. Minimal necessary value of the signal to interference power ratio is measured under the given reception criteria. Results are useful for broadcasting networks planning. Different DRM Plus modes (i.e. combinations of various protection levels and data carriers modulations are assumed in the case of DRM Plus reception interfered with by FM broadcasting. The differences for various modes are crucial for coverage design of DRM Plus system, while protection ratios have been recommended for only two of eight modes until now. Corrections of protection ratios for other modes are proposed in this paper. Different waveforms types of modulating signal for interfering FM signal are tested. The both mono and stereo FM mode and various sound quality criteria are considered in the case of FM broadcasting reception interfered with by DRM Plus. The influence of peak to average power ratio reduction of interfering DRM Plus signal is observed.

  5. Radar and wind turbines; Radar en windturbines

    Energy Technology Data Exchange (ETDEWEB)

    Van Doorn, H.

    2010-03-15

    In the last years the developments of wind parks were hampered because of their possible effect on the radar for observation of air traffic. Work is currently being done on a new assessment model for wind turbines under the auspices of the steering group National Security for the military radar systems. Air traffic control Netherlands (LVNL) will look at the options for civil radars to join in. [Dutch] In de afgelopen jaren zijn windparkontwikkelingen onder meer belemmerd vanwege mogelijke effecten op radar voor de waarneming van luchtverkeer. Onder auspicien van de stuurgroep Nationale Veiligheid voor de militaire radarsystemen op land wordt gewerkt aan een nieuw beoordelingsmodel voor windturbines. De Luchtverkeersleiding Nederland (LVNL) zal bezien in hoeverre de civiele radars hierbij kunnen aansluiten.

  6. Analysis of intra-pulse frequency-modulated, low probability of interception, radar signals

    Indian Academy of Sciences (India)

    A R SACHIN; SOORAJ K AMBAT; K V S HARI

    2017-07-01

    In this paper, we investigate the problem of analysis of low probability of interception (LPI) radar signals with intra-pulse frequency modulation (FM) under low signal-to-noise ratio conditions from the perspective of an airborne electronic warfare (EW) digital receiver. EW receivers are designed to intercept andanalyse threat radar signals of different classes, received over large dynamic range and operating independently over large geographical spread to advice host aircraft to undertake specified actions. For an EW receiver, primary challenges in interception and analysis of LPI radar signals are low received power, intra-pulse modulations,multi-octave frequency range, wide signal bandwidth, long pulse width, vast and multi-parametric search space, etc. In the present work, a method based on match filterbank localization and Taylor’s seriesapproximation for analysing the entire family of intra-pulse FM radar signals is proposed. The method involves progressive, joint time–frequency (TF) localization of the signal of interest (SOI), under piecewise linearity andcontinuity assumptions on instantaneous frequency, to effectively capture local TF signatures. Detection is by information-theoretic criterion based hypotheses testing, while estimation and classification are based on polynomial approximation. Fine signal analysis is followed by synthetic reconstruction of the received signal slope. Detection, estimation and classification performances for the prominent FM radar signal classes are quantified based on simulation study statistics. Stagewise implementation of analysis and FM slope reconstruction,in realistic radar threat scenarios, is demonstrated for the potential SOIs. Subject discussion is organized from the perspective of practical EW system design and presented within the realm of signal processing architecture of concurrent EW digital receivers.Keywords. Digital receiver (DRx); electronic warfare (

  7. FM-CW Based Miniature SAR System for Small UAVs

    NARCIS (Netherlands)

    Hoogeboom, P.; Wit, J.J.M. de; Meta, A.; Figueras, J.

    2005-01-01

    In some earth observation applications there is a requirement for low cost, high performance imaging radar systems small enough to be operated from small, even unmanned, aircraft. The existing pulse radars are non-cost effective complex systems. Therefore they are not suited for these applications.

  8. Pulse Doppler radar

    CERN Document Server

    Alabaster, Clive

    2012-01-01

    This book is a practitioner's guide to all aspects of pulse Doppler radar. It concentrates on airborne military radar systems since they are the most used, most complex, and most interesting of the pulse Doppler radars; however, ground-based and non-military systems are also included. It covers the fundamental science, signal processing, hardware issues, systems design and case studies of typical systems. It will be a useful resource for engineers of all types (hardware, software and systems), academics, post-graduate students, scientists in radar and radar electronic warfare sectors and milit

  9. Understanding radar systems

    CERN Document Server

    Kingsley, Simon

    1999-01-01

    What is radar? What systems are currently in use? How do they work? This book provides engineers and scientists with answers to these critical questions, focusing on actual radar systems in use today. It is a perfect resource for those just entering the field, or as a quick refresher for experienced practitioners. The book leads readers through the specialized language and calculations that comprise the complex world of radar engineering as seen in dozens of state-of-the-art radar systems. An easy to read, wide ranging guide to the world of modern radar systems.

  10. Study on Domain Model of AM/FM/GIS%AM/FM/GIS领域模型研究

    Institute of Scientific and Technical Information of China (English)

    张书亮; 石富兰; 闾国年

    2004-01-01

    通过分析当前AM/FM/GIS在国内外日趋广泛的现状,作者指出AM/FM/GIS软件系统建设过程中存在的主要问题--软件可重用性差,指出其存在潜在的规律和本质的特征,通过找到这些规律和特征将能明显改善AM/FM/GIS系统建设的重用性.作者利用FODA的领域分析方法,对AM/FM/GIS系统进行了深入的研究,通过符合标准规范的表示方法,得到了领域特征模型、领域信息模型和领域操作模型,从不同的侧面精确描述了AM/FM/GIS的领域模型.

  11. [Lasers].

    Science.gov (United States)

    Passeron, T

    2012-11-01

    Lasers are a very effective approach for treating many hyperpigmented lesions. They are the gold standard treatment for actinic lentigos and dermal hypermelanocytosis, such as Ota nevus. Becker nevus, hyperpigmented mosaicisms, and lentigines can also be successfully treated with lasers, but they could be less effective and relapses can be observed. However, lasers cannot be proposed for all types of hyperpigmentation. Thus, freckles and café-au-lait macules should not be treated as the relapses are nearly constant. Due to its complex pathophysiology, melasma has a special place in hyperpigmented dermatoses. Q-switched lasers (using standard parameters or low fluency) should not be used because of consistent relapses and the high risk of post-inflammatory hyperpigmentation. Paradoxically, targeting the vascular component of the melasma lesion with lasers could have a beneficial effect. However, these results have yet to be confirmed. In all cases, a precise diagnosis of the type of hyperpigmentation is mandatory before any laser treatment, and the limits and the potential side effects of the treatment must be clearly explained to patients. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  12. Lasers.

    Science.gov (United States)

    Passeron, T

    2012-12-01

    Lasers are a very effective approach for treating many hyperpigmented lesions. They are the gold standard treatment for actinic lentigos and dermal hypermelanocytosis, such as Ota nevus. Becker nevus, hyperpigmented mosaicisms, and lentigines can also be successfully treated with lasers, but they could be less effective and relapses can be observed. However, lasers cannot be proposed for all types of hyperpigmentation. Thus, freckles and café-au-lait macules should not be treated as the relapses are nearly constant. Due to its complex pathophysiology, melasma has a special place in hyperpigmented dermatoses. Q-switched lasers (using standard parameters or low fluency) should not be used because of consistent relapses and the high risk of post-inflammatory hyperpigmentation. Paradoxically, targeting the vascular component of the melasma lesion with lasers could have a beneficial effect. However, these results have yet to be confirmed. In all cases, a precise diagnosis of the type of hyperpigmentation is mandatory before any laser treatment, and the limits and the potential side effects of the treatment must be clearly explained to patients. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  13. Multidimensional radar picture

    Science.gov (United States)

    Waz, Mariusz

    2010-05-01

    In marine navigation systems, the three-dimensional (3D) visualization is often and often used. Echosonders and sonars working in hydroacustic systems can present pictures in three dimensions. Currently, vector maps also offer 3D presentation. This presentation is used in aviation and underwater navigation. In the nearest future three-dimensional presentation may be obligatory presentation in displays of navigation systems. A part of these systems work with radar and communicates with it transmitting data in a digital form. 3D presentation of radar picture require a new technology to develop. In the first step it is necessary to compile digital form of radar signal. The modern navigation radar do not present data in three-dimensional form. Progress in technology of digital signal processing make it possible to create multidimensional radar pictures. For instance, the RSC (Radar Scan Converter) - digital radar picture recording and transforming tool can be used to create new picture online. Using RSC and techniques of modern computer graphics multidimensional radar pictures can be generated. The radar pictures mentioned should be readable for ECDIS. The paper presents a method for generating multidimensional radar picture from original signal coming from radar receiver.

  14. GEOS RR Lyr survey: FM Del is indeed a cepheid

    CERN Document Server

    Borgne, Jean-Francois Le

    2014-01-01

    Though FM Del has been considered as a RR Lyr star by Preston et al. in 1959 (following discovery by Huth, 1957), Huth (1960) eventually changed his mind by showing that it is in fact a cepheid of W Vir type of period of 3.95452 days. Various authors since then have considered it as a cepheid indeed, with the exception of Wils et al. (2006) who list this star in their RR Lyr catalog with a period of 0.79688 days. On this basis, FM Del was added to Tarot RR Lyr program. We present here these observations which confirm the cepheid type.

  15. The Resonance 107.3 FM Radio Art Collection

    DEFF Research Database (Denmark)

    Nielsen, Katrine; Kreutzfeldt, Jacob

    2016-01-01

    This article investigates the collection of Resonance 107.3 FM, which has recently become digitally accessible for research at the British Library Sound Archive. Documenting the full extent of a 28-day event by the London Musicians Collective in 1998 the collection offers unique insight into early...... in metadata as well as in memories and texts. Applying this method of recalling, describing and reflecting to three examples of live-experimentation from the Resonance 107.3 FM collection, this article illustrates that archives of minor media and practises in community and art radio are valuable resources...

  16. Simulation Research on Obstacle Avoidance Planning for Mobile Robot Based on Laser Radar%基于激光雷达的移动机器人避障规划仿真研究

    Institute of Scientific and Technical Information of China (English)

    刘杰; 闫清东; 唐正华

    2015-01-01

    Through improving the traditional Vector Field Histogram ( VFH ) algorithm, a kind of outdoor obstacle avoidance planning algorithm for laser radar is proposed. Based on the laser radar and adaptive threshold, through the planning of the target course,the algorithm gets the real-time obstacle avoidance direction of the robot. When there are obstacles between the robot and the target point,the robot obtains the target heading with the maximum threshold. When between the robot and the target point without obstacles,the minimum threshold is used for robots which do not collide with obstacles. Simulation result shows that, when the robot speed is below 0. 8 m/s, it can be safely and smoothly through the complex obstacle area,gets to the goal;Otherwise,the robot gets to the goal with slight rub.%对传统矢量场直方图算法进行改进,使其成为一种适用于将激光雷达作为探测仪的室外避障规划算法。将激光雷达数据作为依据,以自适应阈值为条件,通过对目标航向进行规划,获得机器人行进方向的实时避障算法。当机器人与目标点之间存在障碍物时,以最大阈值获得机器人的目标航向,而当机器人与目标点之间无障碍物时,以最小阈值确保机器人行进过程不会与障碍物发生碰撞。仿真结果表明,在复杂障碍物环境中,当机器人行进速度低于0.8 m/s时,可安全而平滑地通过障碍区,到达目标点;当机器人的行进速度高于0.8 m/s时,虽速度过快,机器人与平台之间会有轻微的剐蹭,但最终亦能到达目标点。

  17. 基于脑机接口与双激光雷达的移动车导航系统%Vehicle Navigation System Based on BCI and Dual Laser Radar

    Institute of Scientific and Technical Information of China (English)

    孟丽霞; 陶霖密; 孙富春; 刘华平; 褚涛

    2012-01-01

    针对脑机接口信噪比低、准确率差和延时长等问题,提出了基于机器智能辅助的室外移动机器人脑机接口导航方法.设计并实现了一个基于脑机接口与双激光雷达的移动车导航系统.该系统首先采用了基于双激光雷达的改进的角度势场法进行局部路径规划,然后结合脑机接口系统获取的导航意图,经过融合决策给出控制命令,驱动一辆经过机械系统改装的电动汽车.实验表明,该系统能根据环境障碍信息和脑机控制意图实现智能避障与人机协同导航,具有更高的准确性、容错性和鲁棒性.%A machine intelligence assistant BCI (brain-computer interface) navigation method for an outdoor mobile robot is put forward in view of the problem of BCI's low signal-to-noise ratio, bad accuracy and long time delay. A vehicle navigation system based on BCI and dual laser radar is designed and implemented. Firstly, an improved angle potential field method based on dual laser radar is used for local path planning, then with navigation intention from BCI system, control commands are generated by fusion decision and used for driving a electric vehicle with modified mechanical system. Experiments show that the system can realize intelligent obstacle avoidance and human-machine collaborative navigation based on environmental obstacle information and brain-machine interface control intention, and it has higher accuracy, tolerance and robustness.

  18. Radar based autonomous sensor module

    Science.gov (United States)

    Styles, Tim

    2016-10-01

    Most surveillance systems combine camera sensors with other detection sensors that trigger an alert to a human operator when an object is detected. The detection sensors typically require careful installation and configuration for each application and there is a significant burden on the operator to react to each alert by viewing camera video feeds. A demonstration system known as Sensing for Asset Protection with Integrated Electronic Networked Technology (SAPIENT) has been developed to address these issues using Autonomous Sensor Modules (ASM) and a central High Level Decision Making Module (HLDMM) that can fuse the detections from multiple sensors. This paper describes the 24 GHz radar based ASM, which provides an all-weather, low power and license exempt solution to the problem of wide area surveillance. The radar module autonomously configures itself in response to tasks provided by the HLDMM, steering the transmit beam and setting range resolution and power levels for optimum performance. The results show the detection and classification performance for pedestrians and vehicles in an area of interest, which can be modified by the HLDMM without physical adjustment. The module uses range-Doppler processing for reliable detection of moving objects and combines Radar Cross Section and micro-Doppler characteristics for object classification. Objects are classified as pedestrian or vehicle, with vehicle sub classes based on size. Detections are reported only if the object is detected in a task coverage area and it is classified as an object of interest. The system was shown in a perimeter protection scenario using multiple radar ASMs, laser scanners, thermal cameras and visible band cameras. This combination of sensors enabled the HLDMM to generate reliable alerts with improved discrimination of objects and behaviours of interest.

  19. Principles and Limitations of Ultra-Wideband FM Communications Systems

    Directory of Open Access Journals (Sweden)

    Kouwenhoven Michiel HL

    2005-01-01

    Full Text Available This paper presents a novel UWB communications system using double FM: a low-modulation index digital FSK followed by a high-modulation index analog FM to create a constant-envelope UWB signal. FDMA techniques at the subcarrier level are exploited to accommodate multiple users. The system is intended for low (1–10 kbps and medium (100–1000 kbps bit rate, and short-range WPAN systems. A wideband delay-line FM demodulator that is not preceded by any limiting amplifier constitutes the key component of the UWBFM receiver. This unusual approach permits multiple users to share the same RF bandwidth. Multipath, however, may limit the useful subcarrier bandwidth to one octave. This paper addresses the performance with AWGN and multipath, the resistance to narrowband interference, as well as the simultaneous detection of multiple FM signals at the same carrier frequency. SPICE and Matlab simulation results illustrate the principles and limitations of this new technology. A hardware demonstrator has been realized and has allowed the confirmation of theory with practical results.

  20. 47 CFR 73.319 - FM multiplex subcarrier technical standards.

    Science.gov (United States)

    2010-10-01

    ... subcarriers except those used for stereophonic sound broadcasts under the provisions of § 73.322. (b... range of 20 kHz to 99 kHz. (2) During stereophonic sound program transmissions (see § 73.322), multiplex... requiring any mechanical or electrical modifications in the transmitter FM exciter circuits. (f)...

  1. Thermal Properties of Bazhen fm. Sediments from Thermal Core Logging

    Science.gov (United States)

    Spasennykh, Mikhail; Popov, Evgeny; Popov, Yury; Chekhonin, Evgeny; Romushkevich, Raisa; Zagranovskaya, Dzhuliya; Belenkaya, Irina; Zhukov, Vladislav; Karpov, Igor; Saveliev, Egor; Gabova, Anastasia

    2016-04-01

    The Bazhen formation (B. fm.) is the hugest self-contained source-and-reservoir continuous petroleum system covering by more than 1 mln. km2 (West Siberia, Russia). High lithological differentiation in Bazhen deposits dominated by silicic shales and carbonates accompanied by extremely high total organic carbon values (of up to 35%), pyrite content and brittle mineralogical composition deteriorate standard thermal properties assessment for low permeable rocks. Reliable information of unconventional system thermal characteristics is the necessary part of works such as modelling of different processes in reservoir under thermal EOR for accessing their efficiency, developing and optimizing design of the oil recovery methods, interpretation of the well temperature logging data and for the basin petroleum modelling. A unique set of data including thermal conductivity, thermal diffusivity, volumetric heat capacity, thermal anisotropy for the B.fm. rocks was obtained from thermal core logging (high resolution continuous thermal profiling) on more than 4680 core samples (2000 of B.fm. samples are among) along seven wells for four oil fields. Some systematic peculiarities of the relation between thermal properties of the B.fm. rocks and their mineralogical composition, structural and texture properties were obtained. The high-resolution data are processed jointly with the standard petrophysical logging that allowed us to provide better separation of the formation. The research work was done with financial support of the Russian Ministry of Education and Science (unique identification number RFMEFI58114X0008).

  2. FM knowledge – theoretical foundation and application in practice

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2017-01-01

    The idea behind this special issue can be dated back to a whole day workshop that I organised on 7 November 2012 at our Centre for Facilities Management – Realdania Research (CFM), Technical University of Denmark. The title of the workshop was “Added Value and Advancements in FM knowledge...

  3. 75 FR 65521 - FM Approvals; Expansion of Recognition

    Science.gov (United States)

    2010-10-25

    ... convenience, we may use the designation of the standards-developing organization for the standard as opposed... by 29 CFR 1910.7: 1. FM must allow OSHA access to its facilities and records to ascertain continuing... inform OSHA as soon as possible, in writing, of any change of ownership, facilities, or key...

  4. Effects of noise reduction on AM and FM perception.

    Science.gov (United States)

    Ives, D Timothy; Calcus, Axelle; Kalluri, Sridhar; Strelcyk, Olaf; Sheft, Stanley; Lorenzi, Christian

    2013-02-01

    The goal of noise reduction (NR) algorithms in digital hearing aid devices is to reduce background noise whilst preserving as much of the original signal as possible. These algorithms may increase the signal-to-noise ratio (SNR) in an ideal case, but they generally fail to improve speech intelligibility. However, due to the complex nature of speech, it is difficult to disentangle the numerous low- and high-level effects of NR that may underlie the lack of speech perception benefits. The goal of this study was to better understand why NR algorithms do not improve speech intelligibility by investigating the effects of NR on the ability to discriminate two basic acoustic features, namely amplitude modulation (AM) and frequency modulation (FM) cues, known to be crucial for speech identification in quiet and in noise. Here, discrimination of complex, non-linguistic AM and FM patterns was measured for normal hearing listeners using a same/different task. The stimuli were generated by modulating 1-kHz pure tones by either a two-component AM or FM modulator with patterns changed by manipulating component phases. Modulation rates were centered on 3 Hz. Discrimination of AM and FM patterns was measured in quiet and in the presence of a white noise that had been passed through a gammatone filter centered on 1 kHz. The noise was presented at SNRs ranging from -6 to +12 dB. Stimuli were left as such or processed via an NR algorithm based on the spectral subtraction method. NR was found to yield small but systematic improvements in discrimination for the AM conditions at favorable SNRs but had little effect, if any, on FM discrimination. A computational model of early auditory processing was developed to quantify the fidelity of AM and FM transmission. The model captured the improvement in discrimination performance for AM stimuli at high SNRs with NR. However, the model also predicted a relatively small detrimental effect of NR for FM stimuli in contrast with the average

  5. Ku-Band radar penetration into Snow over Arctic Sea Ice

    DEFF Research Database (Denmark)

    Hendricks, Stefan; Stenseng, Lars; Helm, Veit

    Sea ice freeboard measurements are of great interest for basin-scale ice mass balance monitoring. Typically, laser- and radar-altimeters are used for freeboard retrieval in operational systems such as aircrafts and satellites. For laser beams it can be assumed that the dominant reflector......, if radar altimeters are capable of measuring the distance to the snow-ice interface reliably. We present the results of aircraft campaigns in the Arctic with a scanning laser altimeter and the Airborne SAR/Interferometric Radar Altimeter System (ASIRAS) of the European Space Agency. The elevation...... observations are converted into freeboard profiles, taking the different footprints into account when comparing the two systems. Based on the probability distribution of laser and radar freeboard we discuss the specific characteristics of both systems and the apparent radar penetration over sea ice...

  6. Magnetostriction of FM/TbFe (FM=Fe, Py-permalloy, FeCo) coupled bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Li Jianjun, E-mail: ljj8081@tom.com [National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin150080 (China); Laboratoire de Magnetisme de Bretagne-CNRS FRE 3117, Universite de Bretagne Occidentale, 6, Avenue le Gorgeu C.S. 93837, 29238 Brest Cedex 3 (France)

    2012-04-15

    Choosing TbFe as the magnetostrictive layer and using soft ferromagnetic materials (FM=Fe, Py-permalloy, FeCo) as the inductive layer, we report the magnetization and magnetostriction of the S/FM(10 nm)/TbFe(10 nm) coupled bilayer (S-glass substrate). The magnetization of the coupled bilayer is attributed to the soft ferromagnetic layer and there is no contribution from the TbFe layer. Interfacial exchange interaction plays an important role in determining the magnetostriction of the coupled bilayer. The effect coming from the deposition Argon pressure on the magnetostriction of the coupled bilayer was also investigated. - Highlights: Black-Right-Pointing-Pointer Choosing TbFe as magnetostrictive layer and with soft ferromagnetic material (FM=Fe, Py-permalloy, FeCo) as inductive layer. Black-Right-Pointing-Pointer We report the magnetization and magnetostriction of the S/FM(10 nm)/TbFe(10 nm) coupled bilayer (S-glass substrate). Black-Right-Pointing-Pointer The magnetization of coupled bilayer is attributed to soft ferromagnetic layer and there is no contribution from TbFe layer. Black-Right-Pointing-Pointer Interfacial exchange interaction plays an important role in determining the magnetostriction of the coupled bilayer.

  7. Phased-array radar design application of radar fundamentals

    CERN Document Server

    Jeffrey, Thomas

    2009-01-01

    Phased-Array Radar Design is a text-reference designed for electrical engineering graduate students in colleges and universities as well as for corporate in-house training programs for radar design engineers, especially systems engineers and analysts who would like to gain hands-on, practical knowledge and skills in radar design fundamentals, advanced radar concepts, trade-offs for radar design and radar performance analysis.

  8. Radar Signature Calculation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: The calculation, analysis, and visualization of the spatially extended radar signatures of complex objects such as ships in a sea multipath environment and...

  9. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  10. Radar cross section measurements using terahertz waves

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    Radar cross sections at terahertz frequencies are measured on scale models of aircrafts. A time domain broadband THz system generates freely propagating THz pulses measured with sub-picosecond time resolution. The THz radiation is generated using fs laser pulses by optical rectification in a lith......Radar cross sections at terahertz frequencies are measured on scale models of aircrafts. A time domain broadband THz system generates freely propagating THz pulses measured with sub-picosecond time resolution. The THz radiation is generated using fs laser pulses by optical rectification...... in a lithium niobate crystal with application of the tilted wave front method, resulting in high electric field THz pulses with a broad band spectrum from 100 GHz up to 4 THz. The corresponding wave lengths are two orders of magnitude smaller than normal radars and we therefore use scale models of size 5-10 cm...... in order to measure realistic radar cross sections. RCS polar and azimuthal angle plots of F-16 and F-35 are presented....

  11. Combined radar and telemetry system

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbeck, Christopher T.; Young, Derek; Chou, Tina; Hsieh, Lung-Hwa; Conover, Kurt; Heintzleman, Richard

    2017-08-01

    A combined radar and telemetry system is described. The combined radar and telemetry system includes a processing unit that executes instructions, where the instructions define a radar waveform and a telemetry waveform. The processor outputs a digital baseband signal based upon the instructions, where the digital baseband signal is based upon the radar waveform and the telemetry waveform. A radar and telemetry circuit transmits, simultaneously, a radar signal and telemetry signal based upon the digital baseband signal.

  12. Radar Sensing for Intelligent Vehicles in Urban Environments

    Directory of Open Access Journals (Sweden)

    Giulio Reina

    2015-06-01

    Full Text Available Radar overcomes the shortcomings of laser, stereovision, and sonar because it can operate successfully in dusty, foggy, blizzard-blinding, and poorly lit scenarios. This paper presents a novel method for ground and obstacle segmentation based on radar sensing. The algorithm operates directly in the sensor frame, without the need for a separate synchronised navigation source, calibration parameters describing the location of the radar in the vehicle frame, or the geometric restrictions made in the previous main method in the field. Experimental results are presented in various urban scenarios to validate this approach, showing its potential applicability for advanced driving assistance systems and autonomous vehicle operations.

  13. Design and Implementation of FM Wave Generator Base on FPGA%基于FPGA的FM信号发生器设计与实现

    Institute of Scientific and Technical Information of China (English)

    左盼盼; 赛景波

    2016-01-01

    In order to improve the frequency accuracy and stability of the FM signal generator,and make it relevant technical parameters adjustable,a method is designed based on FPGA and Direct Digital Synthesizer(DDS)technol⁃ogy. The system achieves adjustable FM signal modulation parameters by the PC,and through the PCIE interfaceFM signal control word is transferred to the FPGA,FPGA controls the integrated DDS core to achieve the FM signal gen⁃eration. Test results show that the frequency of FM signal has high frequency accuracy and stability,the maximum output of the carrier frequency can reach 40 MHz,and the amplitude accuracy can reach 5 mV. The FM signal gener⁃ator has a broad application space in software radio,radar target feature identification and radar detection distance and other fields.%为提高FM信号发生器的频率准确度和稳定度,并使其相关技术参数可调,设计了一种基于FPGA和直接数字频率合成(DDS)技术的产生方法。系统通过上位机设置FM信号的调制参数,通过PCIE接口将上位机设置的FM信号控制字传给FPGA,FPGA内部通过控制DDS核来实现FM信号的产生。测试结果表明,FM信号的频率精度高且稳定性好,最高输出载波频率达40 MHz,幅度精度能达到5 mV。该FM信号发生器在软件无线电、雷达目标特征识别和雷达距离探测等领域具有广阔的应用空间。

  14. Trending Technologies for Indoor FM: Looking for "Geo" in Information

    Science.gov (United States)

    Gunduz, M.; Isikdag, U.; Basaraner, M.

    2016-10-01

    Today technological developments in the Architecture Engineering and Construction (AEC) industry provides opportunities to build huge and complex buildings and facilities. In order to operate these facilities and to meet the requirements of the occupants and also to manage energy, waste and to keep all facility services operational, several Facility Management (FM) solutions were developed. This paper starts by presenting a state of art review of research related to Indoor Facility Management Systems. Later, a textual analysis focused to identify the research trends in this field is presented in the paper. The result of the literature review and textual analysis indicates that current research in Indoor FM Systems is underestimating the role of Geoinformation, Geoinformation models and systems.

  15. Doppler-radar wind-speed measurements in tornadoes: A comparison of real and simulated spectra

    Energy Technology Data Exchange (ETDEWEB)

    Bluestein, H.B.; LaDue, J.G.; Stein, H.; Speheger, D. (Oklahoma Univ., Norman, OK (United States)); Unruh, W.P. (Los Alamos National Lab., NM (United States))

    1993-01-01

    Bluestein and Unruh have discussed the advantages of using a portable doppler radar to map the wind field in tornadoes. during the spring of 1991 a storm-intercept team from the University of Oklahoma (OU) collected data near five supercell tornadoes in Oklahoma and Kansas. Details about the 1-W, 3-cm, 5-deg half-power beamwidth, CW/FM-CW Doppler radar we used and the methods of data collection and analysis are found in Bluestein and Unruh and Bluestein et al. Using the portable radar, we approximately doubled in only one year the number of tornado spectra that had been collected over a period of almost 20 years by NSSL's fixed-site Doppler radar. In this paper we will compare observed tornado wind spectra with simulated wind spectra (Zmic and Doviak 1975) in order to learn more about tornado structure.

  16. Radar illusion via metamaterials

    Science.gov (United States)

    Jiang, Wei Xiang; Cui, Tie Jun

    2011-02-01

    An optical illusion is an image of a real target perceived by the eye that is deceptive or misleading due to a physiological illusion or a specific visual trick. The recently developed metamaterials provide efficient approaches to generate a perfect optical illusion. However, all existing research on metamaterial illusions has been limited to theory and numerical simulations. Here, we propose the concept of a radar illusion, which can make the electromagnetic (EM) image of a target gathered by radar look like a different target, and we realize a radar illusion device experimentally to change the radar image of a metallic target into a dielectric target with predesigned size and material parameters. It is well known that the radar signatures of metallic and dielectric objects are significantly different. However, when a metallic target is enclosed by the proposed illusion device, its EM scattering characteristics will be identical to that of a predesigned dielectric object under the illumination of radar waves. Such an illusion device will confuse the radar, and hence the real EM properties of the metallic target cannot be perceived. We designed and fabricated the radar illusion device using artificial metamaterials in the microwave frequency, and good illusion performances are observed in the experimental results.

  17. Java Radar Analysis Tool

    Science.gov (United States)

    Zaczek, Mariusz P.

    2005-01-01

    Java Radar Analysis Tool (JRAT) is a computer program for analyzing two-dimensional (2D) scatter plots derived from radar returns showing pieces of the disintegrating Space Shuttle Columbia. JRAT can also be applied to similar plots representing radar returns showing aviation accidents, and to scatter plots in general. The 2D scatter plots include overhead map views and side altitude views. The superposition of points in these views makes searching difficult. JRAT enables three-dimensional (3D) viewing: by use of a mouse and keyboard, the user can rotate to any desired viewing angle. The 3D view can include overlaid trajectories and search footprints to enhance situational awareness in searching for pieces. JRAT also enables playback: time-tagged radar-return data can be displayed in time order and an animated 3D model can be moved through the scene to show the locations of the Columbia (or other vehicle) at the times of the corresponding radar events. The combination of overlays and playback enables the user to correlate a radar return with a position of the vehicle to determine whether the return is valid. JRAT can optionally filter single radar returns, enabling the user to selectively hide or highlight a desired radar return.

  18. Determination of radar MTF

    Energy Technology Data Exchange (ETDEWEB)

    Chambers, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The ultimate goal of the Current Meter Array (CMA) is to be able to compare the current patterns detected with the array with radar images of the water surface. The internal wave current patterns modulate the waves on the water surface giving a detectable modulation of the radar cross-section (RCS). The function relating the RCS modulations to the current patterns is the Modulation Transfer Function (MTF). By comparing radar images directly with co-located CMA measurements the MTF can be determined. In this talk radar images and CMA measurements from a recent experiment at Loch Linnhe, Scotland, will be used to make the first direct determination of MTF for an X and S band radar at low grazing angles. The technical problems associated with comparing radar images to CMA data will be explained and the solution method discussed. The results suggest the both current and strain rate contribute equally to the radar modulation for X band. For S band, the strain rate contributes more than the current. The magnitude of the MTF and the RCS modulations are consistent with previous estimates when the wind is blowing perpendicular to the radar look direction.

  19. Aspects of Radar Polarimetry

    OpenAIRE

    Lüneburg, Ernst

    2002-01-01

    This contribution is a tutorial introduction to the phenomenological theory of radar polarimetry for the coherent scatter case emphasizing monostatic backscattering and forward scattering (transmission). Characteristic similarities and differences between radar polarimetry and optical polarimetry and the role of linear and antilinear operators (time-reversal) are pointed out and typical polarimetric invariants are identified.

  20. The Cloud Radar System

    Science.gov (United States)

    Racette, Paul; Heymsfield, Gerald; Li, Lihua; Tian, Lin; Zenker, Ed

    2003-01-01

    Improvement in our understanding of the radiative impact of clouds on the climate system requires a comprehensive view of clouds including their physical dimensions, dynamical generation processes, and detailed microphysical properties. To this end, millimeter vave radar is a powerful tool by which clouds can be remotely sensed. The NASA Goddard Space Flight Center has developed the Cloud Radar System (CRS). CRS is a highly sensitive 94 GHz (W-band) pulsed-Doppler polarimetric radar that is designed to fly on board the NASA high-altitude ER-2 aircraft. The instrument is currently the only millimeter wave radar capable of cloud and precipitation measurements from above most all clouds. Because it operates from high-altitude, the CRS provides a unique measurement perspective for cirrus cloud studies. The CRS emulates a satellite view of clouds and precipitation systems thus providing valuable measurements for the implementation and algorithm validation for the upcoming NASA CloudSat mission that is designed to measure ice cloud distributions on the global scale using a spaceborne 94 GHz radar. This paper describes the CRS instrument and preliminary data from the recent Cirrus Regional Study of Tropical Anvils and Cirrus Layers - Florida Area Cirrus Experiment (CRYSTAL-FACE). The radar design is discussed. Characteristics of the radar are given. A block diagram illustrating functional components of the radar is shown. The performance of the CRS during the CRYSTAL-FACE campaign is discussed.

  1. Analytical Approaches to Guide SLS Fault Management (FM) Development

    Science.gov (United States)

    Patterson, Jonathan D.

    2012-01-01

    Extensive analysis is needed to determine the right set of FM capabilities to provide the most coverage without significantly increasing the cost, reliability (FP/FN), and complexity of the overall vehicle systems. Strong collaboration with the stakeholders is required to support the determination of the best triggers and response options. The SLS Fault Management process has been documented in the Space Launch System Program (SLSP) Fault Management Plan (SLS-PLAN-085).

  2. Micropower impulse radar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hall, M.S.

    1995-11-01

    From designs developed at the Lawrence Livermore National Laboratory (LLNL) in radar and imaging technologies, there exists the potential for a variety of applications in both public and private sectors. Presently tests are being conducted for the detection of buried mines and the analysis of civil structures. These new systems use a patented ultra-wide band (impulse) radar technology known as Micropower Impulse Radar (GPR) imaging systems. LLNL has also developed signal processing software capable of producing 2-D and 3-D images of objects embedded in materials such as soil, wood and concrete. My assignment while at LLNL has focused on the testing of different radar configurations and applications, as well as assisting in the creation of computer algorithms which enable the radar to scan target areas of different geometeries.

  3. 基于重采样技术的调频连续波激光绝对测距高精度及快速测量方法研究∗%High precision and fast metho d for absolute distance measurement based on resampling technique used in FM continuous wave laser ranging

    Institute of Scientific and Technical Information of China (English)

    孟祥松; 张福民; 曲兴华

    2015-01-01

    Frequency modulated continuous wave (FMCW) laser ranging is one of the most interesting techniques for precision distance metrology. It is a promising candidate for absolute distance measurement at large standoff distances (10 to 100 m) with high precision and accuracy, and no cooperation target is needed during the measuring process. How to improve the measurement resolution in practice has been the research focus of the FMCW laser ranging in recent years. FMCW laser ranging system uses the method which may convert the measurement of flight time to the frequency measurement, while the ranging resolution can be determined by the tuning range of the optical frequency sweep in theory. The main impact-factor that reduces the resolution is the tuning nonlinearity of the laser source, which may cause an amount of error points within the sampling signal. So a dual-interferometric FMCW laser ranging system is adopted in this paper. Compared to the traditional Michelson scheme, an assistant interferometer is added. The assistant interferometer has an all-fiber optical Mach-Zehnder configuration, and the delay distance is at least 2 times longer than OPD (optical path difference) of the main interferometer. Because it provides the reference length, the length of the fiber must remain unchanged. The interference signal is obtained on the photodetector. At the time points of every peak and bottom of the auxiliary interferometer signal, the beating signal from the main interferometer is re-sampled. The original signal is not the equal time intervals, while the re-sampled signal is the equal optical frequency intervals. Based on the property of the re-sampled signal, a method by splicing the re-sampled signal to optimize the signal processing is proposed, by which the tuning range of the laser source limitation can be broken and high precision can be easily obtained. Also, a simple high-speed measuring method is proposed. Based on all the above principles, the two-fiber optical

  4. Principles of modern radar radar applications

    CERN Document Server

    Scheer, James A

    2013-01-01

    Principles of Modern Radar: Radar Applications is the third of the three-volume seriesof what was originally designed to be accomplished in one volume. As the final volumeof the set, it finishes the original vision of a complete yet bounded reference for radartechnology. This volume describes fifteen different system applications or class ofapplications in more detail than can be found in Volumes I or II.As different as the applications described, there is a difference in how these topicsare treated by the authors. Whereas in Volumes I and II there is strict adherence tochapter format and leve

  5. To procure for better buildings - FM and Public Private Partnerships in Denmark

    DEFF Research Database (Denmark)

    Kristiansen, Kristian

    Purpose: The paper is based on a research project investigating whether PPP´s are good for the procurement of FM, i.e. are PPP´s advantageous for the integration of FM considerations into the planning, design and construction of buildings? Background: In Public-Private Partnerships FM services...

  6. E-Learning Readiness in Medicine: Turkish Family Medicine (FM) Physicians Case

    Science.gov (United States)

    Parlakkiliç, Alaattin

    2015-01-01

    This research investigates e-learning readiness level of family medicine physicians (FM) in Turkey. The study measures the level of e-learning readiness of Turkish FM physicians by an online e-learning readiness survey. According to results five areas are ready at Turkish FM physicians but need a few improvements:…

  7. Parametric dependence of ocean wave-radar modulation transfer functions

    Science.gov (United States)

    Plant, W. J.; Keller, W. C.; Cross, A.

    1983-01-01

    Microwave techniques at X and L band were used to determine the dependence of ocean-wave radar modulation transfer functions (MTFs) on various environmental and radar parameters during the Marine Remote Sensing experiment of 1979 (MARSEN 79). These MIF are presented, as are coherence functions between the AM and FM parts of the backscattered microwave signal. It is shown that they both depend on several of these parameters. Besides confirming many of the properties of transfer functions reported by previous authors, indications are found that MTFs decrease with increasing angle between wave propagation and antenna-look directions but are essentially independent of small changes in air-sea temperature difference. However, coherence functions are much smaller when the antennas are pointed perpendicular to long waves. It is found that X band transfer functions measured with horizontally polarized microwave radiation have larger magnitudes than those obtained by using vertical polarization.

  8. 激光雷达窄脉冲回波信号采集系统设计%Design of narrow pulse echo signal acquisition system of laser radar

    Institute of Scientific and Technical Information of China (English)

    杨腾蛟; 史建业; 丁尚; 叶凌云

    2015-01-01

    Laser radar emits narrow pulse signal,which produces echo after exposure to target object,the echo can be converted to electrical pulse signal by avalanche photoelectric sensor. Aiming at nanosecond level electric pulse,propose 8 GSPS high-speed parallel sampling scheme and channel correction solution. Simulation and experimental results show that avalanche photoelectric sensor performs narrow pulse responsiveness very well, channel correction scheme weakens effect of channel mismatch on system. System completes real-time sampling of 4 ns narrow pulse echo signal.%激光雷达发射出窄脉冲激光信号,在照射到目标物体后产生回波,由雪崩型光电传感器将其转换为电脉冲信号。针对该ns级电脉冲,提出8GSPS高速并行采样方案与通道校正方案。仿真与实验结果表明:雪崩型光电传感器具备良好的窄脉冲响应能力,高速并行采样可以实现窄脉冲信号采集重构,通道校正方案减少了通道失配对系统的影响。系统完成对4 ns窄脉冲回波信号的实时采样。

  9. Real-time windowing in imaging radar using FPGA technique

    Science.gov (United States)

    Ponomaryov, Volodymyr I.; Escamilla-Hernandez, Enrique

    2005-02-01

    The imaging radar uses the high frequency electromagnetic waves reflected from different objects for estimating of its parameters. Pulse compression is a standard signal processing technique used to minimize the peak transmission power and to maximize SNR, and to get a better resolution. Usually the pulse compression can be achieved using a matched filter. The level of the side-lobes in the imaging radar can be reduced using the special weighting function processing. There are very known different weighting functions: Hamming, Hanning, Blackman, Chebyshev, Blackman-Harris, Kaiser-Bessel, etc., widely used in the signal processing applications. Field Programmable Gate Arrays (FPGAs) offers great benefits like instantaneous implementation, dynamic reconfiguration, design, and field programmability. This reconfiguration makes FPGAs a better solution over custom-made integrated circuits. This work aims at demonstrating a reasonably flexible implementation of FM-linear signal and pulse compression using Matlab, Simulink, and System Generator. Employing FPGA and mentioned software we have proposed the pulse compression design on FPGA using classical and novel windows technique to reduce the side-lobes level. This permits increasing the detection ability of the small or nearly placed targets in imaging radar. The advantage of FPGA that can do parallelism in real time processing permits to realize the proposed algorithms. The paper also presents the experimental results of proposed windowing procedure in the marine radar with such the parameters: signal is linear FM (Chirp); frequency deviation DF is 9.375MHz; the pulse width T is 3.2μs taps number in the matched filter is 800 taps; sampling frequency 253.125*106 MHz. It has been realized the reducing of side-lobes levels in real time permitting better resolution of the small targets.

  10. Laser Heterodyning

    CERN Document Server

    Protopopov, Vladimir V

    2009-01-01

    Laser heterodyning is now a widespread optical technique, based on interference of two waves with slightly different frequencies within the sensitive area of a photo-detector. Its unique feature – preserving phase information about optical wave in the electrical signal of the photo-detector – finds numerous applications in various domains of applied optics and optoelectronics: in spectroscopy, polarimetry, radiometry, laser radars and Lidars, microscopy and other areas. The reader may be surprised by a variety of disciplines that this book covers and satisfied by detailed explanation of the phenomena. Very well illustrated, this book will be helpful for researches, postgraduates and students, working in applied optics.

  11. Radar cross section

    CERN Document Server

    Knott, Gene; Tuley, Michael

    2004-01-01

    This is the second edition of the first and foremost book on this subject for self-study, training, and course work. Radar cross section (RCS) is a comparison of two radar signal strengths. One is the strength of the radar beam sweeping over a target, the other is the strength of the reflected echo sensed by the receiver. This book shows how the RCS ?gauge? can be predicted for theoretical objects and how it can be measured for real targets. Predicting RCS is not easy, even for simple objects like spheres or cylinders, but this book explains the two ?exact? forms of theory so well that even a

  12. Radar and electronic navigation

    CERN Document Server

    Sonnenberg, G J

    2013-01-01

    Radar and Electronic Navigation, Sixth Edition discusses radar in marine navigation, underwater navigational aids, direction finding, the Decca navigator system, and the Omega system. The book also describes the Loran system for position fixing, the navy navigation satellite system, and the global positioning system (GPS). It reviews the principles, operation, presentations, specifications, and uses of radar. It also describes GPS, a real time position-fixing system in three dimensions (longitude, latitude, altitude), plus velocity information with Universal Time Coordinated (UTC). It is accur

  13. The Normal Color Vision Evaluated With FM 100-hue Test

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    One hundred and twenty normal subjects (240 eyes) agedfrom 10 to 69 were tested with FM 100-hue test.They were divided into6 groups according to their age.It was shown that there were no statisti-cally significant difference in the total error score (TES) between the malesand females or between the right and left eyes,but there existed some rela-tionships between the TES and age.The total error score (TES) was thelowest in the 20-29 age group and increased gradually with aging.Theanalysis of the partial...

  14. Creative MuVo2 FM 5GB

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    可存储多达2500首歌曲Creative MuVo2 FM 5GB设计轻巧简洁;尺寸只有67×665×20mm.内置了完备的FM收音/录音和语音录音功能.并设计了全新的摇杆按键,也是即插即用的大容量U盘,更具有高达98dB的信噪比,可更换式充电锂电池,

  15. Feinika FM 1101 W 机械型量表

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Feinika FM 1101 W 机械型防污量表的防护标准为IP67,此外还具有以下特征:测量头被细致装入测量杆,并具有可靠的径向间隙;刻度盘和表圈可以转动,方便调零;用内公差指示器设置公差范围;可换标准测量头,

  16. Potentials for Radio Frequency Identification in AEC/FM

    Institute of Scientific and Technical Information of China (English)

    Karsten Menzel; CONG Zixiang; Luke Allan

    2008-01-01

    Radio frequency identification (RFID) technology has proved to be very effective in industries as di-verse as aircraft manufacturing to health and care. The construction industry has been slow to take up on RFID and this paper will discuss the merits of the technology in its potential for application within the con-struction sector. The paper reports about the prototypical implementation of RFID-based information man-agement in FM-scenarios. The prototypes were tested at University College Cork (UCC). The general appli-cability of RFID for decentralised information management could be demonstrated.

  17. Spectral Features of FM Spectroscopy of Two-Photon Interactions

    Institute of Scientific and Technical Information of China (English)

    夏慧荣; JohnL.Hall

    1994-01-01

    The spectral features of FM two-photon resonant interaction processes have been calculated for five different frequency modulation versions of counter-propagating incident fields. It is found that the proposed new modulation version (case b in the text) provides novel spectral features for a completely canceled absorption and a sharp dispersion shape at the fundamental beat note. Moreover, its absorption feature appears at the second harmonic of the RF modulation frequency generated by the joint modes via six interaction pathways without mutual phase shift. Such features persist even when the effects of the second-order sidebands of the incident fields are taken into account. Application potentials are emphasized.

  18. Microscopic description of 258Fm fission dynamic with pairing

    Directory of Open Access Journals (Sweden)

    Scamps Guillaume

    2016-01-01

    Full Text Available Fission dynamic remains a challenge for nuclear microscopic theories. In order to understand the dynamic of the last stage of the fission process, the time-dependent Hartree-Fock approach with BCS pairing is applied to the describe the fission of the 258Fm. A good agreement is found for the one-body observables: the total kinetic energy and the average mass asymmetry. The non-physical dependence of two-body observables with the initial shape is discussed.

  19. Wind Profiling Radar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Clutter present in radar return signals as used for wind profiling is substantially removed by carrying out a Daubechies wavelet transformation on a time series of...

  20. Imaging Radar Polarimetry

    Science.gov (United States)

    vanZyl, J. J.; Zebker, H. A.

    1993-01-01

    In this paper, we review the state of the art in imaging radar polarimetry, examine current developments in sensor technology and implementation for recording polarimetric measurements, and describe techniques and areas of application for the new remote sensing data.

  1. Radar Landmass Simulation Computer Programming (Interim Report).

    Science.gov (United States)

    RADAR SCANNING, TERRAIN), (*NAVAL TRAINING, RADAR OPERATORS), (*FLIGHT SIMULATORS, TERRAIN AVOIDANCE), (* COMPUTER PROGRAMMING , INSTRUCTION MANUALS), PLAN POSITION INDICATORS, REAL TIME, DISPLAY SYSTEMS, RADAR IMAGES, SIMULATION

  2. 50 CFR 660.392 - Latitude/longitude coordinates defining the 50 fm (91 m) through 75 fm (137 m) depth contours.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Latitude/longitude coordinates defining.../longitude coordinates defining the 50 fm (91 m) through 75 fm (137 m) depth contours. Boundaries for RCAs are defined by straight lines connecting a series of latitude/longitude coordinates. This...

  3. 50 CFR 660.391 - Latitude/longitude coordinates defining the 10-fm (18-m) through 40-fm (73-m) depth contours.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Latitude/longitude coordinates defining.../longitude coordinates defining the 10-fm (18-m) through 40-fm (73-m) depth contours. Boundaries for RCAs are defined by straight lines connecting a series of latitude/longitude coordinates. This section...

  4. 50 CFR 660.393 - Latitude/longitude coordinates defining the 100 fm (183 m) through 150 fm (274 m) depth contours.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Latitude/longitude coordinates defining... Latitude/longitude coordinates defining the 100 fm (183 m) through 150 fm (274 m) depth contours. Boundaries for RCAs are defined by straight lines connecting a series of latitude/longitude coordinates....

  5. 50 CFR 660.394 - Latitude/longitude coordinates defining the 180 fm (329 m) through 250 fm (457 m) depth contours.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Latitude/longitude coordinates defining... Latitude/longitude coordinates defining the 180 fm (329 m) through 250 fm (457 m) depth contours. Boundaries for RCAs are defined by straight lines connecting a series of latitude/longitude coordinates....

  6. Downhole pulse radar

    Science.gov (United States)

    Chang, Hsi-Tien

    1987-09-28

    A borehole logging tool generates a fast rise-time, short duration, high peak-power radar pulse having broad energy distribution between 30 MHz and 300 MHz through a directional transmitting and receiving antennas having barium titanate in the electromagnetically active region to reduce the wavelength to within an order of magnitude of the diameter of the antenna. Radar returns from geological discontinuities are sampled for transmission uphole. 7 figs.

  7. Monitoring of Refractory wall recession using radar technique

    Energy Technology Data Exchange (ETDEWEB)

    University of missouri

    2003-12-30

    Furnaces are the most crucial components in the glass and metallurgical industry. Like any other components in an industry, furnaces require periodic maintenance and repair. Today, furnaces are being operated at higher temperatures and for longer periods of time thus increasing the rate of wear and tear on the furnace refractory lining. As a result of the competitive market facing these industries, longer furnace lifetime with shorter maintenance downtime are increasingly required. Higher fuel consumption, low production and safety are issues that accompany delayed maintenance. Consequently, there is a need to know the state of a refractory wall to prevent premature or unnecessary maintenance shutdowns. For many years the observation skills of an experienced operator has been the primary source of evaluating the wear associated with a refractory wall. The rate of regression of a refractory lining depends on the type of the refractory lining, the materials Monitoring of Refractory Wall Recession Using Frequency-Modulated Continuous-Wave (FM-CW) Radar Techniques: A Proof-of-Concept Study, Final Report, Submitted to the Department of Energy (DOE), September 2003. being melted, seepage, mechanical stresses, and temperature. Moreover, the regression of a refractory lining is also not uniform throughout a furnace and it is more prominent at the metal line along the sidewalls as this region is exposed to hot gaseous byproducts and flowing molten material. Hence, more accurate measurement techniques are required to determine the local residual thickness of a refractory lining so as to utilize the refractory lining to the maximum extent possible. The use of isotope radiators, thermocouples and endoscopes has also been investigated for monitoring regression. These techniques are capable of providing scanned thermal images showing the profile of the refractory wall. However, these techniques can only provide relative profile information and cannot provide absolute thickness

  8. 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

  9. 9-Fluorenylmethyl (Fm) Disulfides: Biomimetic Precursors for Persulfides

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chung-Min; Johnson, Brett A.; Duan, Jicheng; Park, Jeong-Jin; Day, Jacob J.; Gang, David; Qian, Wei-Jun; Xian, Ming

    2016-03-04

    Protein S-sulfhydration has been recognized as an important post-translational modification that regulates H2S signals. However, the reactivity and biological implications of the products of S-sulfhydration, i.e. persulfides, are still unclear. This is mainly due to the instability of persulfides and difficulty to access these molecules. Under physiological conditions persulfides mainly exist in anionic forms because of their low pKa values. However, current methods do not allow for the direct generation of persulfide anions under biomimetic and non-H2S conditions. Herein we report the development of a functional disulfide, FmSSPy-A (Fm =9-fluorenylmethyl; Py = pyridinyl). This reagent can effectively convert both small molecule and protein thiols (-SH) to form –S-SFm adducts under mild conditions. It allows for a H2S-free and biomimetic protocol to generate highly reactive persulfides (in their anionic forms). We also demonstrated the high nucleophilicity of persulfides toward a number of thiol-blocking reagents. This method holds promise for further understanding the chemical biology of persulfides and S-sulfhydration.

  10. Critical behavior of a triangular lattice Ising AF/FM bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Žukovič, M., E-mail: milan.zukovic@upjs.sk; Bobák, A.

    2016-03-06

    We study a bilayer Ising spin system consisting of antiferromagnetic (AF) and ferromagnetic (FM) triangular planes, coupled by ferromagnetic exchange interaction, by standard Monte Carlo and parallel tempering methods. The AF/FM bilayer is found to display the critical behavior completely different from both the single FM and AF constituents as well as the FM/FM and AF/AF bilayers. Namely, by finite-size scaling (FSS) analysis we identify at the same temperature a standard Ising transition from the paramagnetic to FM state in the FM plane that induces a ferrimagnetic state with a finite net magnetic moment in the AF plane. At lower temperatures there is another phase transition, that takes place only in the AF plane, to different ferrimagnetic state with spins on two sublattices pointing parallel and on one sublattice antiparallel to the spins on the FM plane. FSS indicates that the corresponding critical exponents are close to the two-dimensional three-state ferromagnetic Potts model values. - Highlights: • We study critical behavior of a triangular lattice Ising AF/FM bilayer. • Critical properties are studied by Monte Carlo and parallel tempering methods. • Critical exponents are determined from finite-size scaling analysis. • At higher temperature Ising phase transitions in both FM and AF layers are found. • At lower temperature a three-state Potts phase transition in AF layer is found.

  11. Un imageur radar pour la perception et la caractérisation en milieu naturel

    OpenAIRE

    Rouveure, R.; Faure, P; Monod, M.O.

    2010-01-01

    National audience; Le processus de perception demeure un point critique pour les applications en environnement extérieur. Le radar hyperfréquence offre dans ce contexte un potentiel important car il permet de résoudre certaines limitations des capteurs optiques (laser, vision). Un capteur de ce type, nommé K2Pi, a été conçu pour des applications de cartographie de l'environnement. Le radar est associé à l'algorithme R SLAM, développé pour dessiner les cartes radar. La carte radar globale est ...

  12. 基于三维激光雷达的井下巷道场景漫游系统设计%Underground Tunnel Scene Roaming System Design Based on 3D Laser Radar

    Institute of Scientific and Technical Information of China (English)

    蒋盛锋

    2016-01-01

    In order to achieve the underground tunnel internal roaming function ,the whole path roaming system used for the trajectory of the camera during roaming was designed .This system used the 3D laser radar to obtain three‐dimension‐al point cloud data ,first through point cloud processing ,then by determining the next sampling point in the neighborhood and calculated value ,and established centerline branch and extension and connection ,the neighborhood radius extraction roadway centerline was expanded gradually ,according to the user given initial nodes and target nodes ,A * algorithm was used to search the shortest roaming path ,scene roaming was realized .The results showed that ,based on underground tunnel scene roaming of this system meet the large mining roadway internal three‐dimensional scene fast inspection function .%为了实现井下巷道内部漫游功能,设计一种全路径漫游系统,作为快速漫游时视点运动的路径。此系统采用三维激光雷达获取井下三维点云数据,首先经过点云处理,然后经过确定下采样点邻域及计算 L1中值、中线分支的建立和延展及连接,逐渐扩大邻域半径提取巷道的中心线,根据用户给定的初始结点和目标结点利用 A 倡算法搜索最短漫游路径,实现场景漫游。结果表明,基于此系统的巷道场景漫游功能满足了大型矿山三维场景中巷道内部快速巡检的功能。

  13. Digging Surface Three Dimension Reconstruction Method Based on Laser Scanner Radar%一种基于激光扫描雷达的挖掘面3D重构方法

    Institute of Scientific and Technical Information of China (English)

    王钤; 骆云志

    2014-01-01

    For realizing digging robot automatic trajectory generation and tracking, put forwards digging surface 3D reconstruction method. According to triangle principle of 3D laser scanner radar to acquire coordinates of scan point. Use clustering analysis method on scan point to delete noise point. Use initial triangulation, local optimization, coloration, and rendering to acquire flat bottom hole 3D physical model after initial triangulation. Then use inversion prism to fitting, calculate distance between upper surface and bottom surface of flat bottom hole lumen and the geometry size of bottom surface. The practice result shows that the method realizes measurement for irregular flat bottom hole lumen and make foundation for realizing digging robot automatic trajectory generation and tracking in flat bottom hole.%为了实现挖掘机器人自动轨迹生成和轨迹跟踪,提出一种挖掘机器人的挖掘面3D重构方法。根据3D激光扫描雷达的三角形原理得到扫描点的坐标值,对扫描点进行聚类分析方法滤除噪声点,进行初始三角剖分、局部优化、着色和渲染得到三角剖分后平底坑的3D 物理模型,并采用倒置棱台进行拟合,计算了所挖平底坑内腔的上表面和下表面之间的距离和下表面的几何尺寸。实践结果表明:该方法实现了对不规则平底坑内腔的测量,为挖掘机器人自主挖掘平底坑的自动轨迹生成和跟踪奠定了基础。

  14. The Future of FM in the Nordic Countries and a Possible Common Research Agenda

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Andersen, Per Dannemand; Rasmussen, Birgitte

    2012-01-01

    model of the FM sector was developed as a framework for the study. Approach: The study contained four elements. First a review of literature on the future of FM was carried out. Secondly, four national workshops were held involving FM practitioners and researchers from Denmark, Norway, Sweden...... the four countries. Based on the study a common Nordic research agenda is proposed with two headlines: a) Valuation and professionalization of FM and b) Sustainability in FM services. Emphasis is set on the former. Originality/value: This is the first comprehensive foresight study aimed at developing......Purpose: To identify trends and challenges in relation to the FM profession in the Nordic countries and to identify inputs to a common Nordic research agenda. Theory: The study is based on theory from innovation systems and strategic foresight. Based on a literature review an innovation systems...

  15. Behavioral and Molecular Genetics of Reading-Related AM and FM Detection Thresholds.

    Science.gov (United States)

    Bruni, Matthew; Flax, Judy F; Buyske, Steven; Shindhelm, Amber D; Witton, Caroline; Brzustowicz, Linda M; Bartlett, Christopher W

    2017-03-01

    Auditory detection thresholds for certain frequencies of both amplitude modulated (AM) and frequency modulated (FM) dynamic auditory stimuli are associated with reading in typically developing and dyslexic readers. We present the first behavioral and molecular genetic characterization of these two auditory traits. Two extant extended family datasets were given reading tasks and psychoacoustic tasks to determine FM 2 Hz and AM 20 Hz sensitivity thresholds. Univariate heritabilities were significant for both AM (h (2)  = 0.20) and FM (h (2)  = 0.29). Bayesian posterior probability of linkage (PPL) analysis found loci for AM (12q, PPL = 81 %) and FM (10p, PPL = 32 %; 20q, PPL = 65 %). Bivariate heritability analyses revealed that FM is genetically correlated with reading, while AM was not. Bivariate PPL analysis indicates that FM loci (10p, 20q) are not also associated with reading.

  16. Composite technology in radar equipment. Dopler Meteo radar reflector device

    Directory of Open Access Journals (Sweden)

    A. V. Shumov

    2014-01-01

    Full Text Available The article is devoted features of the application composite materials in radar technology for example adjustment of the development technology of the reflector antenna device DMRL-S - radar for monitoring meteorological conditions.Russian and foreign analogues DMRL-S are made of aluminum, which no longer meets modern requirements for strength and weight. Also aluminum reflectors are not temperature stable. Composite materials are characterized by higher values of specific characteristics: temporary resistance, endurance limit, stiffness, elastic modulus, and less prone to cracking. The use of such materials improves the strength, rigidity and durability.For the manufacture of the DMRL-C reflector used composite materials based on epoxy resins reinforced with fiberglass (both unidirectional and woven. To increase the rigidity and weight reflector is made in the form of three-layer sandwich fiberglass panels with honeycomb core variable height. Design work was carried out in a CAD Siemens NX8.0 / Unigraphics, through which was established mathematical model layered reflector, as well as all accessories used in the manufacture. With the program NX Nastran was held strength calculation and analysis of stiffness on the finite element method.After the manufacture of the product, we measured the standard deviation of the working surface of the reflector from the theoretical surface using a three-dimensional laser scanner. Measurements were made at different angular positions of the reflector, and when loading. It is shown that the maximum strain in the operating modes of operation across the surface of the product does not exceed 4%, which will provide the most accurate operation of the product in any position of the antenna system.As a result of this work reflector design was developed, created and verified by experimental data calculation model. Reflector antenna device of the DMRL-S was manufactured and tested. The reflector was made of reinforced

  17. Micropower impulse radar technology and applications

    Energy Technology Data Exchange (ETDEWEB)

    Mast, J., LLNL

    1998-04-15

    The LLNL-developed Micropower Impulse Radar (MIR) technology has quickly gone from laboratory concept to embedded circuitry in numerous government and commercial systems in the last few years[l]. The main ideas behind MIR, invented by T. McEwan in the Laser Program, are the generation and detection systems for extremely low- power ultra-wideband pulses in the gigaHertz regime using low-cost components. These ideas, coupled with new antenna systems, timing and radio-frequency (RF) circuitry, computer interfaces, and signal processing, have provided the catalyst for a new generation of compact radar systems. Over the past several years we have concentrated on a number of applications of MIR which address a number of remote-sensing applications relevant to emerging programs in defense, transportation, medical, and environmental research. Some of the past commercial successes have been widely publicized [2] and are only now starting to become available for market. Over 30 patents have been filed and over 15 licenses have been signed on various aspects of the MIR technology. In addition, higher performance systems are under development for specific laboratory programs and government reimbursables. The MIR is an ultra- wideband, range-gated radar system that provides the enabling hardware technology used in the research areas mentioned above. It has numerous performance parameters that can be Selected by careful design to fit the requirements. We have improved the baseline, short- range, MIR system to demonstrate its effectiveness. The radar operates over the hand from approximately I to 4 GHz with pulse repetition frequencies up to 10 MHz. It provides a potential range resolution of I cm at ranges of greater than 20 m. We have developed a suite of algorithms for using MIR for image formation. These algorithms currently support Synthetic aperture and multistate array geometries. This baseline MIR radar imaging system has been used for several programmatic applications.

  18. A barrier radar concept

    Science.gov (United States)

    Marshall, J.; Ball, C.; Weissman, I.

    A description is given of a low power, light-weight radar that can be quickly set up and operated on batteries for extended periods of time to detect airborne intruders. With low equipment and operating costs, it becomes practical to employ a multiplicity of such radars to provide an unbroken intrusion fence over the desired perimeter. Each radar establishes a single transmitted fan beam extending vertically from horizon to horizon. The beam is generated by a two-face array antenna built in an A-frame configuration and is shaped, through phasing of the array elements, to concentrate the transmitter power in a manner consistent with the expected operating altitude ceiling of the targets of interest. The angular width of this beam in the dimension transverse to the fan depends on the radar transmission frequency and the antenna aperture dimension, but is typically wide enough so that a target at the maximum altitude or range will require tens of seconds to pass through the beam. A large number of independent samples of radar data will thus be available to provide many opportunities for target detection.

  19. Coherent Laser Instrument Would Measure Range and Velocity

    Science.gov (United States)

    Chang, Daniel; Cardell, Greg; San Martin, Alejandro; Spiers, Gary

    2005-01-01

    A proposed instrument would project a narrow laser beam that would be frequency-modulated with a pseudorandom noise (PN) code for simultaneous measurement of range and velocity along the beam. The instrument performs these functions in a low mass, power, and volume package using a novel combination of established techniques. Originally intended as a low resource- footprint guidance sensor for descent and landing of small spacecraft onto Mars or small bodies (e.g., asteroids), the basic instrument concept also lends itself well to a similar application guiding aircraft (especially, small unmanned aircraft), and to such other applications as ranging of topographical features and measuring velocities of airborne light-scattering particles as wind indicators. Several key features of the instrument s design contribute to its favorable performance and resource-consumption characteristics. A laser beam is intrinsically much narrower (for the same exit aperture telescope or antenna) than a radar beam, eliminating the need to correct for the effect of sloping terrain over the beam width, as is the case with radar. Furthermore, the use of continuous-wave (CW), erbium-doped fiber lasers with excellent spectral purity (narrow line width) permits greater velocity resolution, while reducing the laser s power requirement compared to a more typical pulsed solid-state laser. The use of CW also takes proper advantage of the increased sensitivity of coherent detection, necessary in the first place for direct measurement of velocity using the Doppler effect. However, measuring range with a CW beam requires modulation to "tag" portions of it for time-of-flight determination; typically, the modulation consists of a PN code. A novel element of the instrument s design is the use of frequency modulation (FM) to accomplish both the PN-modulation and the Doppler-bias frequency shift necessary for signed velocity measurements. This permits the use of a single low-power waveguide electrooptic

  20. Airport Surveillance Radar : Model 8 -

    Data.gov (United States)

    Department of Transportation — The Airport Surveillance Radar Model 8 (ASR-8) is a short-range (60 nautical mile (nmi)), analog radar system used to detect and report the presence and location of...

  1. Airport Surveillance Radar : Model 7 -

    Data.gov (United States)

    Department of Transportation — The Airport Surveillance Radar Model 7 (ASR-7) is a short-range (60 nautical miles (nmi)) analog radar system used to detect and report the presence and location of...

  2. Acoustic change detection algorithm using an FM radio

    Science.gov (United States)

    Goldman, Geoffrey H.; Wolfe, Owen

    2012-06-01

    The U.S. Army is interested in developing low-cost, low-power, non-line-of-sight sensors for monitoring human activity. One modality that is often overlooked is active acoustics using sources of opportunity such as speech or music. Active acoustics can be used to detect human activity by generating acoustic images of an area at different times, then testing for changes among the imagery. A change detection algorithm was developed to detect physical changes in a building, such as a door changing positions or a large box being moved using acoustics sources of opportunity. The algorithm is based on cross correlating the acoustic signal measured from two microphones. The performance of the algorithm was shown using data generated with a hand-held FM radio as a sound source and two microphones. The algorithm could detect a door being opened in a hallway.

  3. The start of a Nordic focus on the added value of FM

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Malmstrøm, Ole Emil

    2012-01-01

    Purpose: To contribute to the understanding and demonstration of added value of FM based on the results of a NordicFM workgroup. Methodology: The basic understanding of FM and added value developed by the workgroup is presented together with 13 cases, which are analysed to find new general insigh...... is only to a limited degree based on scientific research and mostly based on the experiences and practical innovations among the workgroup participants. Originality/value: The chapter presents the birth of a joint focus on the added value of FM in the Nordic countries....

  4. Strategic FM Procurement: an issue of aligning services to business needs

    DEFF Research Database (Denmark)

    Katchamart, Akarapong; Shiem-shin, Danny Then

    2014-01-01

    Purpose – To illustrate the interdependence between business need and strategic decision on facilities management (FM) procurement model. This interdependence underpins the reason behind strategic decision on FM procurement. It would assist decision makers on FM services procurement that fulfills...... on a limited number of detailed case studies, further empirical verification of various types of organizations and contexts will be needed. Originality/value Although this proposed approach is formulated within the context of FM procurement, its applications can be applied to other organizational support...

  5. Radar for tracer particles

    CERN Document Server

    Ott, Felix; Huang, Kai

    2016-01-01

    We introduce a radar system capable of tracking a $5$mm spherical target continuously in three dimensions. The $10$GHz (X-band) radar system has a transmission power of $1$W and operates in the near field of the horn antennae. By comparing the phase shift of the electromagnetic wave traveling through the free space with an IQ-Mixer, we obtain the relative movement of the target with respect to the antennae. From the azimuth and inclination angles of the receiving antennae obtained in the calibration, we reconstruct the target trajectory in a three-dimensional Cartesian system. Finally, we test the tracking algorithm with target moving in circular as well as in pendulum motions, and discuss the capability of the radar system.

  6. Localizing Ground-Penetrating Radar

    Science.gov (United States)

    2014-11-01

    ing Ground-Penetrating Radar (LGPR) uses very high frequency (VHF) radar reflections of underground features to generate base- line maps and then...Innovative ground- penetrating radar that maps underground geological features provides autonomous vehicles with real-time localization. Localizing...NOV 2014 2. REPORT TYPE 3. DATES COVERED 00-00-2014 to 00-00-2014 4. TITLE AND SUBTITLE Localizing Ground-Penetrating Radar 5a. CONTRACT NUMBER

  7. Mode S Baseline Radar Tracking.

    Science.gov (United States)

    1982-11-01

    range units and 20 azimuth units) overlaying the position of the beacon reports. In the cases analyzed where beacon reports were not radar reinforced ...82/53 j~ C ~ 7 C _ _ _ _ _ _ 4. Title end Su.btitle 5. Neget at. November 1982 MDDE S BASELINE RADAR TRACKIN4G 6. Poelin Orgeuianti.. Cede ACT-100...Ground Clutter 33 Mode S/ARTS III 100-Scan False Radar Track Summary 74 34 Percent Beacon Radar Reinforcement 77 vii INTRODUCTION PURPOSE. The purpose of

  8. Systems and Methods for Radar Data Communication

    Science.gov (United States)

    Bunch, Brian (Inventor); Szeto, Roland (Inventor); Miller, Brad (Inventor)

    2013-01-01

    A radar information processing system is operable to process high bandwidth radar information received from a radar system into low bandwidth radar information that may be communicated to a low bandwidth connection coupled to an electronic flight bag (EFB). An exemplary embodiment receives radar information from a radar system, the radar information communicated from the radar system at a first bandwidth; processes the received radar information into processed radar information, the processed radar information configured for communication over a connection operable at a second bandwidth, the second bandwidth lower than the first bandwidth; and communicates the radar information from a radar system, the radar information communicated from the radar system at a first bandwidth.

  9. Noise Radar Technology Basics

    Science.gov (United States)

    2006-12-01

    poursuite, estimation Doppler, polarimétrie, interférométrie, sondage du sol ou profilage de la sous- surface , détection, imagerie SAR (radar à synthèse...mesure de distance et d’estimation Doppler. Deux récepteurs de traitement cohérent, soit le récepteur de corrélation et le récep- teur de traitement DSP... traitement spectral double) des échos radar sont décrits et une estimation de leur portée est présentée. Les capacités LPI (faible probabilité

  10. Ground penetrating radar

    CERN Document Server

    Daniels, David J

    2004-01-01

    Ground-penetrating radar has come to public attention in recent criminal investigations, but has actually been a developing and maturing remote sensing field for some time. In the light of recent expansion of the technique to a wide range of applications, the need for an up-to-date reference has become pressing. This fully revised and expanded edition of the best-selling Surface-Penetrating Radar (IEE, 1996) presents, for the non-specialist user or engineer, all the key elements of this technique, which span several disciplines including electromagnetics, geophysics and signal processing. The

  11. Human walking estimation with radar

    NARCIS (Netherlands)

    Dorp, Ph. van; Groen, F.C.A.

    2003-01-01

    Radar can be used to observe humans that are obscured by objects such as walls. These humans cannot be visually observed. The radar measurements are used to animate an obscured human in virtual reality. This requires detailed information about the motion. The radar measurements give detailed informa

  12. Radar Test Range Design Considerations.

    Science.gov (United States)

    1980-04-29

    radar cross section associated with dihedral and trihedral corner reflectors is highly dependent upon the squareness or alignment of the...slightly misaligned. We now show how the radar cross section for dihedral and trihedral corner reflectors depends upon their surface misalignment. All...coefficients, p and q, for the dihedral corner reflector , one must consider the radar cross section

  13. Status Of Imaging Radar Polarimetry

    Science.gov (United States)

    Van Zyl, Jakob J.; Zebker, Howard A.

    1991-01-01

    Report pulls together information on imaging radar polarimetry from a variety of sources. Topics include theory, equipment, and experimental data. Reviews state of the art, examines current applicable developments in radar equipment, describes recording and processing of radar polarimetric measurements, and discusses interpretation and application of resulting polarimetric images.

  14. Human walking estimation with radar

    NARCIS (Netherlands)

    Dorp, Ph. van; Groen, F.C.A.

    2003-01-01

    Radar can be used to observe humans that are obscured by objects such as walls. These humans cannot be visually observed. The radar measurements are used to animate an obscured human in virtual reality. This requires detailed information about the motion. The radar measurements give detailed

  15. Coded continuous wave meteor radar

    OpenAIRE

    2015-01-01

    The concept of coded continuous wave meteor radar is introduced. The radar uses a continuously transmitted pseudo-random waveform, which has several advantages: coding avoids range aliased echoes, which are often seen with commonly used pulsed specular meteor radars (SMRs); continuous transmissions maximize pulse compression gain, allowing operation with significantly lower peak transmit power; the temporal resolution can be changed after ...

  16. Bistatic weak target detection method using non-cooperative air surveillance radar

    Institute of Scientific and Technical Information of China (English)

    Zengping Chen

    2015-01-01

    At present, most of the passive radar system re-searches utilize FM radios, TV broadcasts, navigation satel ites, etc. as il uminators. The transmitted signals are not specifical y de-signed radar waveforms. In this work, the frequency agile, phased array air surveil ance radar (ASR) is used as the il uminator of opportunity to detect the weak target. The phased array tech-nology can help realize beam agility to track targets from diffe-rent aspects simultaneously. The frequency agility technology is widely employed in radar system design to increase the ability of anti-jamming and increase the detection probability. While the fre-quency bandwidth of radar signals is usual y wide and the range resolution is high, the range cel migration effect is obvious during the long time integration of non-cooperative bistatic radar. In this context, coherent integration methods are not applicable. In this work, a parametric non-coherent integration algorithm based on task de-interweaving is proposed. Numerical experiments verify that this is effective in weak target detection.

  17. Exact spectrum of non-linear chirp scaling and its application in geosynchronous synthetic aperture radar imaging

    Directory of Open Access Journals (Sweden)

    Chen Qi

    2013-07-01

    Full Text Available Non-linear chirp scaling (NLCS is a feasible method to deal with time-variant frequency modulation (FM rate problem in synthetic aperture radar (SAR imaging. However, approximations in derivation of NLCS spectrum lead to performance decline in some cases. Presented is the exact spectrum of the NLCS function. Simulation with a geosynchronous synthetic aperture radar (GEO-SAR configuration is implemented. The results show that using the presented spectrum can significantly improve imaging performance, and the NLCS algorithm is suitable for GEO-SAR imaging after modification.

  18. Single Chip Implementation for RF Reception of FM-SCA Radio Paging%FM-SCA无线寻呼射频的单片接收

    Institute of Scientific and Technical Information of China (English)

    吴建辉; 宋慧滨; 时龙兴; 孙大有

    2000-01-01

    首先介绍了FM-SCA无线寻呼的传统接收结构,重点提出超外差与零中频相结合以单片化实现FM-SCA射频接收的拓朴结构,并给出了数学推导,证明了该拓朴结构能有效地恢复出原始信号.

  19. The Newcastle meteor radar

    Science.gov (United States)

    Keay, Colin

    1987-01-01

    A brief history and development of the Newcastle Meteor Radar system is given. Also described are its geographical coordinates and its method of operation. The initial objective when the project was commenced was to develop an entirely digital analyzer capable of recognizing meteor echo signals and recording as many of their parameters as possible. This objective was achieved.

  20. Compressive CFAR radar detection

    NARCIS (Netherlands)

    Anitori, L.; Otten, M.P.G.; Rossum, W.L. van; Maleki, A.; Baraniuk, R.

    2012-01-01

    In this paper we develop the first Compressive Sensing (CS) adaptive radar detector. We propose three novel architectures and demonstrate how a classical Constant False Alarm Rate (CFAR) detector can be combined with ℓ1-norm minimization. Using asymptotic arguments and the Complex Approximate Messag

  1. Compressive CFAR Radar Processing

    NARCIS (Netherlands)

    Anitori, L.; Rossum, W.L. van; Otten, M.P.G.; Maleki, A.; Baraniuk, R.

    2013-01-01

    In this paper we investigate the performance of a combined Compressive Sensing (CS) Constant False Alarm Rate (CFAR) radar processor under different interference scenarios using both the Cell Averaging (CA) and Order Statistic (OS) CFAR detectors. Using the properties of the Complex Approximate Mess

  2. Synthetic Aperture Radar Interferometry

    Science.gov (United States)

    Rosen, P. A.; Hensley, S.; Joughin, I. R.; Li, F.; Madsen, S. N.; Rodriguez, E.; Goldstein, R. M.

    1998-01-01

    Synthetic aperture radar interferometry is an imaging technique for measuring the topography of a surface, its changes over time, and other changes in the detailed characteristics of the surface. This paper reviews the techniques of interferometry, systems and limitations, and applications in a rapidly growing area of science and engineering.

  3. Spaceborne Radar Study

    Science.gov (United States)

    1974-06-28

    via either the oomm beam or the omnichannel . Satellite instrumentation data are sent to the ground station following every radar signal transmission...If comm beam contact is lost, the instrumentation data are sent via the omnichannel transmitter on command of the ground station. There are six ways

  4. Radar Observations of Asteroids

    Science.gov (United States)

    Ostro, S. J.

    2003-05-01

    During the past 25 years, radar investigations have provided otherwise unavailable information about the physical and dynamical properties of more than 200 asteroids. Measurements of the distribution of echo power in time delay and Doppler frequency provide two-dimensional images with spatial resolution as fine as a decameter. Sequences of delay-Doppler images can be used to produce geologically detailed three-dimensional models, to define the rotation state precisely, to constrain the internal density distribution, and to estimate the trajectory of the object's center of mass. Radar wavelengths (4 to 13 cm) and the observer's control of transmitted and received polarizations make the observations sensitive to near-surface bulk density and macroscopic structure. Since delay-Doppler positional measurements are orthogonal to optical angle measurements and typically have much finer fractional precision, they are powerful for refining orbits and prediction ephemerides. Radar astrometry can add decades or centuries to the interval over which an asteroid's close Earth approaches can accurately be predicted and can significantly refine collision probability estimates based on optical astrometry alone. In the highly unlikely case that a small body is on course for an Earth collision in this century, radar reconnaissance would almost immediately distinguish between an impact trajectory and a near miss and would dramatically reduce the difficulty and cost of any effort to prevent the collision. The sizes and rotation periods of radar-detected asteroids span more than four orders of magnitude. These observations have revealed both stony and metallic objects, elongated and nonconvex shapes as well as nearly featureless spheroids, small-scale morphology ranging from smoother than the lunar regolith to rougher than the rockiest terrain on Mars, craters and diverse linear structures, non-principal-axis spin states, contact binaries, and binary systems.

  5. 75 FR 9439 - FM Approvals: Application for Expansion of Recognition; Wyle Laboratories: Voluntary Modification...

    Science.gov (United States)

    2010-03-02

    ... Detectors for Fire Protective Signaling Systems UL 1480 Speakers for Fire Alarm, Emergency, and Commercial... Signaling FM 3210 Heat Detectors for Automatic Fire Alarm Signaling FM 7260 Electrostatic Finishing... Boards UL 917 Clock-Operated Switches UL 1022 Line Isolated Monitors UL 1047 Isolated Power Systems...

  6. Mf 2008, , (SLAM!FM t. Minister van EZ en Radio 538)

    NARCIS (Netherlands)

    W. Hins

    2007-01-01

    Bij de verdeling van FM-radiofrequenties in 1983 heeft SLAM!FM een frequentiepakket verworven voor recente bijzondere muziek. Haar toezegging om slechts een gering percentage hitmuziek uit te zenden was daarbij doorslaggevend. Later ontstaan problemen over de vraag wat ‘hitmuziek’ eigenlijk is. De r

  7. Wideband FM demodulation by injection-locked division of frequency deviation

    NARCIS (Netherlands)

    Visweswaran, A.; Long, J.R.; Staszewski, R.B.

    2014-01-01

    A novel and useful wideband FM demodulator operating across an 8 GHz IF bandwidth for application in low-power, wideband heterodyne receivers. The demodulator includes an n-stage ring oscillator that is injection locked to a wideband input signal. Locking to the input frequency, it divides the FM de

  8. Isolation and identification of Paenibacillus sp. FM-6, involved in the biotransformation of albendazole.

    Science.gov (United States)

    Jin, Lei; Zhang, Xiaojun; Sun, Xiumei; Shi, Hui; Li, Tiejun

    2014-10-01

    A strain, designated as FM-6, was isolated from fish. Based on the results of phenotypic, physiological characteristics, genotypic and phylogenetic analysis, strain FM-6 was finally identified as Paenibacillus sp. When albendazole was provided as the sole carbon source, strain FM-6 could grow and transform albendazole. About 82.7 % albendazole (50 mg/L) was transformed by strain FM-6 after 5 days incubation at 30 °C, 160 rpm. With HPLC-MS method, the transforming product of albendazole was researched. Based on the molecular weight and the retention time, product was identified as albendazole sulfoxide and the transforming pathway of albendazole by strain FM-6 was proposed finally. The optimum temperature and pH for the bacterium growth and albendazole transformation by strain FM-6 were both 30 °C and 7.0. Moreover, the optimum concentration of albendazole for the bacterium growth was 50 mg/L. Coupled with practical production, 50 mg/L was the optimum concentration of albendazole transformation for strain FM-6. This study highlights an important potential use of strain FM-6 for producing albendazole sulfoxide.

  9. 77 FR 18815 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2012-03-28

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: The following applicants filed AM or FM proposals to...

  10. 75 FR 1621 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2010-01-12

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... ELDON, MO, To ST. THOMAS, MO; COX RADIO, INC., Station WALR-FM, Facility ID 48728, BPH-20091124ABA, From... 8438, BMP-20091125ABD, From ASHLAND, VA, To POWHATAN, VA; HAMPTONS COMMUNITY RADIO CORPORATION,...

  11. 76 FR 6788 - Radio Broadcasting Services; AM or FM Proposals To Change The Community of License.

    Science.gov (United States)

    2011-02-08

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change The Community of License. AGENCY... 3338, BPH- 20101222ABD, From MARLOW, OK, To LAWTON, OK; FISHER RADIO REGIONAL GROUP, INC., Station KQDI-FM, Facility ID 32386, BPH-20101222ABO, From GREAT FALLS, MT, To HIGHWOOD, MT; THE MONTANA...

  12. 75 FR 51812 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2010-08-23

    ...] [FR Doc No: 2010-20912] FEDERAL COMMUNICATIONS COMMISSION Radio Broadcasting Services; AM or FM... BROADCASTING CORPORATION, Station KWBC, Facility ID 40912, BP-20100712ABU, From NAVASOTA, TX, To COLLEGE..., OR, To ALOHA, OR; IORIO BROADCASTING, INC., Station WNAE-FM, Facility ID 164188,...

  13. 76 FR 22704 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2011-04-22

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: CEDAR COVE BROADCASTING, INC., Station KAVI, Facility ID 173643, BMPED..., BMPED-20110302ABD, From DANBURY, NC, To MADISON, NC; COX RADIO, INC., Station WHIO-FM, Facility ID...

  14. 77 FR 33217 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2012-06-05

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal Communications Commission. ACTION: Notice. SUMMARY: The following applicants filed AM or FM proposals to...

  15. Case note: CBB (SLAM!FM t. Minister van EZ en Radio 538)

    NARCIS (Netherlands)

    Hins, W.

    2008-01-01

    Bij de verdeling van FM-radiofrequenties in 1983 heeft SLAM!FM een frequentiepakket verworven voor recente bijzondere muziek. Haar toezegging om slechts een gering percentage hitmuziek uit te zenden was daarbij doorslaggevend. Later ontstaan problemen over de vraag wat ‘hitmuziek’ eigenlijk is. De r

  16. 47 CFR 73.1210 - TV/FM dual-language broadcasting in Puerto Rico.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false TV/FM dual-language broadcasting in Puerto Rico...-language broadcasting in Puerto Rico. (a) For the purpose of this section, dual-language broadcasting shall... FM broadcast station may devote more than 15 hours per week to dual-language broadcasting, nor...

  17. 47 CFR 73.1570 - Modulation levels: AM, FM, TV and Class A TV aural.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Modulation levels: AM, FM, TV and Class A TV... levels: AM, FM, TV and Class A TV aural. (a) The percentage of modulation is to be maintained at as high... percent (82.5 kHz peak deviation). (3) TV and Class A TV stations. In no case shall the total...

  18. Laser Scanning in Forests

    OpenAIRE

    Håkan Olsson; Juha Hyyppä; Markus Holopainen

    2012-01-01

    The introduction of Airborne Laser Scanning (ALS) to forests has been revolutionary during the last decade. This development was facilitated by combining earlier ranging lidar discoveries [1–5], with experience obtained from full-waveform ranging radar [6,7] to new airborne laser scanning systems which had components such as a GNSS receiver (Global Navigation Satellite System), IMU (Inertial Measurement Unit) and a scanning mechanism. Since the first commercial ALS in 1994, new ALS-based fore...

  19. UAV-Borne Profiling Radar for Forest Research

    Directory of Open Access Journals (Sweden)

    Yuwei Chen

    2017-01-01

    Full Text Available Microwave Radar is an attractive solution for forest mapping and inventories because microwave signals penetrates into the forest canopy and the backscattering signal can provide information regarding the whole forest structure. Satellite-borne and airborne imaging radars have been used in forest resources mapping for many decades. However, their accuracy with respect to the main forest inventory attributes substantially varies depending on the wavelength and techniques used in the estimation. Systems providing canopy backscatter as a function of canopy height are, practically speaking, missing. Therefore, there is a need for a radar system that would enable the scientific community to better understand the radar backscatter response from the forest canopy. Consequently, we undertook a research study to develop an unmanned aerial vehicle (UAV-borne profiling (i.e., waveform radar that could be used to improve the understanding of the radar backscatter response for forestry mapping and inventories. A frequency modulation continuous waveform (FMCW profiling radar, termed FGI-Tomoradar, was introduced, designed and tested. One goal is the total weight of the whole system is less than 7 kg, including the radar system and georeferencing system, with centimetre-level positioning accuracy. Achieving this weight goal would enable the FGI-Tomoradar system to be installed on the Mini-UAV platform. The prototype system had all four linear polarization measuring capabilities, with bistatic configuration in Ku-band. In system performance tests in this study, FGI-Tomoradar was mounted on a manned helicopter together with a Riegl VQ-480-U laser scanner and tested in several flight campaigns performed at the Evo site, Finland. Airborne laser scanning data was simultaneously collected to investigate the differences and similarities of the outputs for the same target area for better understanding the penetration of the microwave signal into the forest canopy

  20. AM-FM Interference Excision in Spread Spectrum Communications via Projection Filtering

    Directory of Open Access Journals (Sweden)

    Patrick J. Loughlin

    2001-01-01

    Full Text Available Recently, Amin et al. introduced a projection filtering method for excising constant amplitude FM jammers from DSSS communications, with minimal distortion to the PN sequence. In this paper, we show that this approach can be applied to AM-FM jammers as well, with a simple modification. Theoretical performance measures (correlator SNR of the AM-FM projection method are derived, and demonstrate that near ideal performance is achieved for unbiased estimates of the jammer parameters. Results showing the effects of estimation errors in the AM and FM of the jammer on SNR are also provided. In general, FM errors cause greater performance degradation than the same level of error in estimating the AM.

  1. Multiple benefits of personal FM system use by children with auditory processing disorder (APD).

    Science.gov (United States)

    Johnston, Kristin N; John, Andrew B; Kreisman, Nicole V; Hall, James W; Crandell, Carl C

    2009-01-01

    Children with auditory processing disorders (APD) were fitted with Phonak EduLink FM devices for home and classroom use. Baseline measures of the children with APD, prior to FM use, documented significantly lower speech-perception scores, evidence of decreased academic performance, and psychosocial problems in comparison to an age- and gender-matched control group. Repeated measures during the school year demonstrated speech-perception improvement in noisy classroom environments as well as significant academic and psychosocial benefits. Compared with the control group, the children with APD showed greater speech-perception advantage with FM technology. Notably, after prolonged FM use, even unaided (no FM device) speech-perception performance was improved in the children with APD, suggesting the possibility of fundamentally enhanced auditory system function.

  2. Aligning BIM with FM: streamlining the process for future projects

    Directory of Open Access Journals (Sweden)

    Colleen Kasprzak

    2012-12-01

    Full Text Available A study performed by the National Institute of Standards and Technology (NIST, USA in 2004 found that owners account for approximately $10.6 billion of the $15.8 billion total inadequate interoperability costs of U.S. capital facility projects in 2002. Because of these inefficiency costs, it becomes vital that information produced during the design and construction phases of a project be transferred into operations with maximum leverage to the end users. However, very few owners have defined these informational needs or developed an integration strategy into existing maintenance management systems. To increase operational efficiency, an organization must first develop an understanding of their operating systems, as well as identify how Building Information Modeling (BIM will add value to their daily tasks. The Pennsylvania State University (PSU has a unique opportunity to diversely implement BIM processes because not only does the University act as an owner, but also as designer and construction manager on the majority of projects. The struggle that PSU faces is one that is unique only to owners with a large, existing, multifaceted building inventory. This paper outlines the current initiative by the Office of Physical Plant (OPP, the asset manager at PSU, to develop an information exchange framework between BIM and FM applications to be used internally. As a result of this research, PSU has been able to define owner operational requirements for future projects and develop a flexible integration framework to support additional BIM tasks and information exchanges.

  3. Aligning BIM with FM: streamlining the process for future projects

    Directory of Open Access Journals (Sweden)

    Colleen Kasprzak

    2015-10-01

    Full Text Available A study performed by the National Institute of Standards and Technology (NIST, USA in 2004 found that owners account for approximately $10.6 billion of the $15.8 billion total inadequate interoperability costs of U.S. capital facility projects in 2002. Because of these inefficiency costs, it becomes vital that information produced during the design and construction phases of a project be transferred into operations with maximum leverage to the end users. However, very few owners have defined these informational needs or developed an integration strategy into existing maintenance management systems. To increase operational efficiency, an organization must first develop an understanding of their operating systems, as well as identify how Building Information Modeling (BIM will add value to their daily tasks. The Pennsylvania State University (PSU has a unique opportunity to diversely implement BIM processes because not only does the University act as an owner, but also as designer and construction manager on the majority of projects. The struggle that PSU faces is one that is unique only to owners with a large, existing, multifaceted building inventory. This paper outlines the current initiative by the Office of Physical Plant (OPP, the asset manager at PSU, to develop an information exchange framework between BIM and FM applications to be used internally. As a result of this research, PSU has been able to define owner operational requirements for future projects and develop a flexible integration framework to support additional BIM tasks and information exchanges.

  4. An MSK Radar Waveform

    Science.gov (United States)

    Quirk, Kevin J.; Srinivasan, Meera

    2012-01-01

    The minimum-shift-keying (MSK) radar waveform is formed by periodically extending a waveform that separately modulates the in-phase and quadrature- phase components of the carrier with offset pulse-shaped pseudo noise (PN) sequences. To generate this waveform, a pair of periodic PN sequences is each passed through a pulse-shaping filter with a half sinusoid impulse response. These shaped PN waveforms are then offset by half a chip time and are separately modulated on the in-phase and quadrature phase components of an RF carrier. This new radar waveform allows an increase in radar resolution without the need for additional spectrum. In addition, it provides self-interference suppression and configurable peak sidelobes. Compared strictly on the basis of the expressions for delay resolution, main-lobe bandwidth, effective Doppler bandwidth, and peak ambiguity sidelobe, it appears that bi-phase coded (BPC) outperforms the new MSK waveform. However, a radar waveform must meet certain constraints imposed by the transmission and reception of the modulation, as well as criteria dictated by the observation. In particular, the phase discontinuity of the BPC waveform presents a significant impediment to the achievement of finer resolutions in radar measurements a limitation that is overcome by using the continuous phase MSK waveform. The phase continuity, and the lower fractional out-of-band power of MSK, increases the allowable bandwidth compared with BPC, resulting in a factor of two increase in the range resolution of the radar. The MSK waveform also has been demonstrated to have an ambiguity sidelobe structure very similar to BPC, where the sidelobe levels can be decreased by increasing the length of the m-sequence used in its generation. This ability to set the peak sidelobe level is advantageous as it allows the system to be configured to a variety of targets, including those with a larger dynamic range. Other conventionally used waveforms that possess an even greater

  5. Radar cross-sectional study using noise radar

    Science.gov (United States)

    Freundorfer, A. P.; Siddiqui, J. Y.; Antar, Y. M. M.

    2015-05-01

    A noise radar system is proposed with capabilities to measure and acquire the radar cross-section (RCS) of targets. The proposed system can cover a noise bandwidth of near DC to 50 GHz. The noise radar RCS measurements were conducted for selective targets like spheres and carpenter squares with and without dielectric bodies for a noise band of 400MHz-5000MHz. The bandwidth of operation was limited by the multiplier and the antennae used.

  6. Netted LPI RADARs

    Science.gov (United States)

    2011-09-01

    easier and, since they cover most of the space around the antenna, can expose it easily at various bearings ). Typical sidelobe levels for conventional...modern radar systems results in an electro- magnetic environment where the receiver should expect very few pulses. Staggered PRF and frequency agility...detector, a logarithmic amplitude compressor , and a signal encoder. All subunits are digitally controlled by computer as to frequency, sweep rate, and

  7. The Radar Roadmap

    Science.gov (United States)

    2013-01-01

    LIMITATION OF ABSTRACT Same as Report ( SAR ) 18. NUMBER OF PAGES 25 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT unclassified c...ABSTRACT Same as Report ( SAR ) 18. NUMBER OF PAGES 25 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b. ABSTRACT unclassified c. THIS PAGE...object bistatic radars. The former allows high resolution without the use of pulse compression techniques and the latter promises cheaper systems by

  8. Radar Investigations of Asteroids

    Science.gov (United States)

    Ostro, S.

    2004-05-01

    Radar investigations have provided otherwise unavailable information about the physical and dynamical properties of about 230 asteroids. Measurements of the distribution of echo power in time delay (range) and Doppler frequency (line-of-sight velocity) provide two-dimensional images with spatial resolution as fine as a decameter. Sequences of delay-Doppler images can be used to produce geologically detailed three-dimensional models, to define the rotation state precisely, to constrain the internal density distribution, and to estimate the trajectory of the object's center of mass. Radar wavelengths (4 to 13 cm) and the observer's control of transmitted and received polarizations make the observations sensitive to near-surface bulk density and macroscopic structure. Since delay-Doppler measurements are orthogonal to optical angle measurements and typically have much finer fractional precision, they are powerful for refining orbits and prediction ephemerides. Such astrometric measurements can add decades or centuries to the interval over which an asteroid's close Earth approaches can accurately be predicted and can significantly refine collision probability estimates based on optical astrometry alone. In the highly unlikely case that a small body is on course for an Earth collision in this century, radar reconnaissance would almost immediately distinguish between an impact trajectory and a near miss and would dramatically reduce the difficulty and cost of any effort to prevent the collision. The sizes and rotation periods of radar-detected asteroids span more than four orders of magnitude. The observations have revealed both stony and metallic objects, elongated and nonconvex shapes as well as nearly featureless spheroids, small-scale morphology ranging from smoother than the lunar regolith to rougher than the rockiest terrain on Mars, craters and diverse linear structures, non-principal-axis spin states, contact binaries, and binary systems.

  9. A Method Applying Gray Image Superposition to Improve Ranging Accuracy in Planar Array Laser Radar%一种直接应用灰度叠加提高面阵激光雷达测距精度的方法

    Institute of Scientific and Technical Information of China (English)

    方毅; 张秀达; 胡剑; 王鹏鹏; 严惠民

    2013-01-01

    相比传统的点扫描激光雷达,基于距离选通和增益调制测距原理的面阵成像激光雷达,具有测距速度快的优点.但同时会引起单帧图像信噪比降低.根据成像激光雷达的原理,建立了其在散粒噪声影响下的测距精度模型,基于该精度模型和机载面阵激光雷达成像的特点,提出了一种应用灰度图像配准叠加提高测距精度的方法.对飞机姿态、光源均匀性、叠加帧数等因素在采用该方法时是否对测距精度有影响进行了分析.分析结果表明,图像完全匹配后,飞机姿态对测距精度没有影响,光源均匀性优于40%时对测距精度影响可以忽略,一定叠加帧数内时灰度叠加不会影响目标之间的相对距离.进行了地面动态实验和机载航拍实验,并将此方法应用于图像的校正,实验结果验证了该方法的有效性.%Compared with traditional point-scanning laser radar, the imaging laser radar based on range gating and gain-modulation ranging principles has faster ranging speed, but at the same time, signal noise ratio (SNR) of single-frame image is lower. According to principles of imaging laser radar, the ranging accuracy model under the influence of shot noise is built. Based on the model and the characteristics of airborne imaging laser radar, a new method which employs the techniques of gray image registration and superposition to improve ranging accuracy is put forward. Then the factors, such as the flight attitude, light uniformity and superposition frame number that influence the application of gray registration and superposition, are analyzed theoretically. The results show that flight attitude has no effect on the method and the light uniformity's effect is small when the uniformity is better than 40%. There will not be other errors between the targets when superposition frame number is within a certain range. A ground of dynamic experiments and aerial experiment are conducted to verify the

  10. Radar clutter classification

    Science.gov (United States)

    Stehwien, Wolfgang

    1989-11-01

    The problem of classifying radar clutter as found on air traffic control radar systems is studied. An algorithm based on Bayes decision theory and the parametric maximum a posteriori probability classifier is developed to perform this classification automatically. This classifier employs a quadratic discriminant function and is optimum for feature vectors that are distributed according to the multivariate normal density. Separable clutter classes are most likely to arise from the analysis of the Doppler spectrum. Specifically, a feature set based on the complex reflection coefficients of the lattice prediction error filter is proposed. The classifier is tested using data recorded from L-band air traffic control radars. The Doppler spectra of these data are examined; the properties of the feature set computed using these data are studied in terms of both the marginal and multivariate statistics. Several strategies involving different numbers of features, class assignments, and data set pretesting according to Doppler frequency and signal to noise ratio were evaluated before settling on a workable algorithm. Final results are presented in terms of experimental misclassification rates and simulated and classified plane position indicator displays.

  11. Nordic Snow Radar Experiment

    Science.gov (United States)

    Lemmetyinen, Juha; Kontu, Anna; Pulliainen, Jouni; Vehviläinen, Juho; Rautiainen, Kimmo; Wiesmann, Andreas; Mätzler, Christian; Werner, Charles; Rott, Helmut; Nagler, Thomas; Schneebeli, Martin; Proksch, Martin; Schüttemeyer, Dirk; Kern, Michael; Davidson, Malcolm W. J.

    2016-09-01

    The objective of the Nordic Snow Radar Experiment (NoSREx) campaign was to provide a continuous time series of active and passive microwave observations of snow cover at a representative location of the Arctic boreal forest area, covering a whole winter season. The activity was a part of Phase A studies for the ESA Earth Explorer 7 candidate mission CoReH2O (Cold Regions Hydrology High-resolution Observatory). The NoSREx campaign, conducted at the Finnish Meteorological Institute Arctic Research Centre (FMI-ARC) in Sodankylä, Finland, hosted a frequency scanning scatterometer operating at frequencies from X- to Ku-band. The radar observations were complemented by a microwave dual-polarization radiometer system operating from X- to W-bands. In situ measurements consisted of manual snow pit measurements at the main test site as well as extensive automated measurements on snow, ground and meteorological parameters. This study provides a summary of the obtained data, detailing measurement protocols for each microwave instrument and in situ reference data. A first analysis of the microwave signatures against snow parameters is given, also comparing observed radar backscattering and microwave emission to predictions of an active/passive forward model. All data, including the raw data observations, are available for research purposes through the European Space Agency and the Finnish Meteorological Institute. A consolidated dataset of observations, comprising the key microwave and in situ observations, is provided through the ESA campaign data portal to enable easy access to the data.

  12. Detection of Weather Radar Clutter

    DEFF Research Database (Denmark)

    Bøvith, Thomas

    2008-01-01

    Weather radars provide valuable information on precipitation in the atmosphere but due to the way radars work, not only precipitation is observed by the weather radar. Weather radar clutter, echoes from non-precipitating targets, occur frequently in the data, resulting in lowered data quality....... Especially in the application of weather radar data in quantitative precipitation estimation and forecasting a high data quality is important. Clutter detection is one of the key components in achieving this goal. This thesis presents three methods for detection of clutter. The methods use supervised...... and precipitating and non-precipitating clouds. Another method uses the difference in the motion field of clutter and precipitation measured between two radar images. Furthermore, the direction of the wind field extracted from a weather model is used. The third method uses information about the refractive index...

  13. FMWC Radar for Breath Detection

    DEFF Research Database (Denmark)

    Suhr, Lau Frejstrup; Tafur Monroy, Idelfonso; Vegas Olmos, Juan José

    We report on the experimental demonstration of an FMCW radar operating in the 25.7 - 26.6 GHz range with a repetition rate of 500 sweeps per second. The radar is able to track the breathing rate of an adult human from a distance of 1 meter. The experiments have utilized a 50 second recording window...... to accurately track the breathing rate. The radar utilizes a saw tooth modulation format and a low latency receiver. A breath tracking radar is useful both in medical scenarios, diagnosing disorders such as sleep apnea, and for home use where the user can monitor its health. Breathing is a central part of every...... radar chip which, through the use of a simple modulation scheme, is able to measure the breathing rate of an adult human from a distance. A high frequency output makes sure that the radar cannot penetrate solid obstacles which is a wanted feature in private homes where people therefore cannot measure...

  14. Modular design and development methodology for robotic multi-axis F/M sensors

    Science.gov (United States)

    Liang, Qiao-Kang; Zhang, Dan; Coppola, Gianmarc; Wu, Wan-Neng; Zou, Kun-Lin; Wang, Yao-Nan; Sun, Wei; Ge, Yun-Jian; Ge, Yu

    2016-04-01

    Accurate Force/Moment (F/M) measurements are required in many applications, and multi-axis F/M sensors have been utilized a wide variety of robotic systems since 1970s. A multi-axis F/M sensor is capable of measuring multiple components of force terms along x-, y-, z-axis (Fx, Fy, Fz), and the moments terms about x-, y- and z-axis (Mx, My and Mz) simultaneously. In this manuscript, we describe experimental and theoretical approaches for using modular Elastic Elements (EE) to efficiently achieve multi-axis, high-performance F/M sensors. Specifically, the proposed approach employs combinations of simple modular elements (e.g. lamella and diaphragm) in monolithic constructions to develop various multi-axis F/M sensors. Models of multi-axis F/M sensors are established, and the experimental results indicate that the new approach could be widely used for development of multi-axis F/M sensors for many other different applications.

  15. Modular design and development methodology for robotic multi-axis F/M sensors.

    Science.gov (United States)

    Liang, Qiao-Kang; Zhang, Dan; Coppola, Gianmarc; Wu, Wan-Neng; Zou, Kun-Lin; Wang, Yao-Nan; Sun, Wei; Ge, Yun-Jian; Ge, Yu

    2016-04-22

    Accurate Force/Moment (F/M) measurements are required in many applications, and multi-axis F/M sensors have been utilized a wide variety of robotic systems since 1970s. A multi-axis F/M sensor is capable of measuring multiple components of force terms along x-, y-, z-axis (Fx, Fy, Fz), and the moments terms about x-, y- and z-axis (Mx, My and Mz) simultaneously. In this manuscript, we describe experimental and theoretical approaches for using modular Elastic Elements (EE) to efficiently achieve multi-axis, high-performance F/M sensors. Specifically, the proposed approach employs combinations of simple modular elements (e.g. lamella and diaphragm) in monolithic constructions to develop various multi-axis F/M sensors. Models of multi-axis F/M sensors are established, and the experimental results indicate that the new approach could be widely used for development of multi-axis F/M sensors for many other different applications.

  16. Preliminary Evidence of Preattentive Distinctions of Frequency-Modulated (FM tones that Convey Affect

    Directory of Open Access Journals (Sweden)

    David I Leitman

    2011-10-01

    Full Text Available Recognizing emotion is an evolutionary imperative. An early stage of auditory scene analysis involves the perceptual grouping of acoustic features, which can be based on both temporal coincidence and spectral features such as perceived pitch. Perceived pitch, or fundamental frequency (F0, is an especially salient cue for differentiating affective intent through speech intonation (prosody. We hypothesized that: 1 simple frequency modulated (FM tone abstractions, based on the parameters of actual prosodic stimuli, would be reliably classified as representing differing emotional categories; and 2 that such differences would yield significant mismatch negativities (MMNs - an index of preattentive deviance detection within the auditory environment. We constructed a set of FM tones that approximated the F0 mean and variation of reliably-recognized happy and neutral prosodic stimuli. These stimuli were presented to 13 subjects using a passive listening oddball paradigm. We additionally included stimuli with no frequency modulation (FM and FM tones with identical carrier frequencies but differing modulation depths as control conditions. Following electrophysiological recording, subjects were asked to identify the sounds they heard as happy, sad, angry or neutral. We observed that FM tones abstracted from happy and no expression speech stimuli elicited MMNs. Post-hoc behavioral testing revealed that subjects reliably identified the FM tones in a consistent manner. Finally, we also observed that FM tones and no-FM tones elicited equivalent MMNs. MMNs to FM tones that differentiate affect suggests that these abstractions may be sufficient to characterize prosodic distinctions, and that these distinctions can be represented in pre-attentive auditory sensory memory.

  17. Detector level ABI spectral response function: FM4 analysis and comparison for different ABI modules

    Science.gov (United States)

    Efremova, Boryana; Pearlman, Aaron J.; Padula, Frank; Wu, Xiangqian

    2016-09-01

    A new generation of imaging instruments Advanced Baseline Imager (ABI) is to be launched aboard the Geostationary Operational Environmental Satellites - R Series (GOES-R). Four ABI flight modules (FM) are planned to be launched on GOES-R,S,T,U, the first one in the fall of 2016. Pre-launch testing is on-going for FM3 and FM4. ABI has 16 spectral channels, six in the visible/near infrared (VNIR 0.47 - 2.25 μm), and ten in the thermal infrared (TIR 3.9 - 13.3 μm) spectral regions, to be calibrated on-orbit by observing respectively a solar diffuser and a blackbody. Each channel has hundreds of detectors arranged in columns. Operationally one Analytic Generation of Spectral Response (ANGEN) function will be used to represent the spectral response function (SRF) of all detectors in a band. The Vendor conducted prelaunch end-to-end SRF testing to compare to ANGEN; detector specific SRF data was taken for: i) best detector selected (BDS) mode - for FM 2,3, and 4; and ii) all detectors (column mode) - for four spectral bands in FM3 and FM4. The GOES-R calibration working group (CWG) has independently used the SRF test data for FM2 and FM3 to study the potential impact of detector-to-detector SRF differences on the ABI detected Earth view radiances. In this paper we expand the CWG analysis to include the FM4 SRF test data - the results are in agreement with the Vendor analysis, and show excellent instrument performance and compare the detector-to-detector SRF differences and their potential impact on the detected Earth view radiances for all of the tested ABI modules.

  18. Radar techniques using array antennas

    CERN Document Server

    Wirth, Wulf-Dieter

    2013-01-01

    Radar Techniques Using Array Antennas is a thorough introduction to the possibilities of radar technology based on electronic steerable and active array antennas. Topics covered include array signal processing, array calibration, adaptive digital beamforming, adaptive monopulse, superresolution, pulse compression, sequential detection, target detection with long pulse series, space-time adaptive processing (STAP), moving target detection using synthetic aperture radar (SAR), target imaging, energy management and system parameter relations. The discussed methods are confirmed by simulation stud

  19. Reconfigurable L-Band Radar

    Science.gov (United States)

    Rincon, Rafael F.

    2008-01-01

    The reconfigurable L-Band radar is an ongoing development at NASA/GSFC that exploits the capability inherently in phased array radar systems with a state-of-the-art data acquisition and real-time processor in order to enable multi-mode measurement techniques in a single radar architecture. The development leverages on the L-Band Imaging Scatterometer, a radar system designed for the development and testing of new radar techniques; and the custom-built DBSAR processor, a highly reconfigurable, high speed data acquisition and processing system. The radar modes currently implemented include scatterometer, synthetic aperture radar, and altimetry; and plans to add new modes such as radiometry and bi-static GNSS signals are being formulated. This development is aimed at enhancing the radar remote sensing capabilities for airborne and spaceborne applications in support of Earth Science and planetary exploration This paper describes the design of the radar and processor systems, explains the operational modes, and discusses preliminary measurements and future plans.

  20. Future Research Agenda for FM in the Nordic Countries in Europe

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Andersen, Per Dannemand; Rasmussen, Birgitte

    2014-01-01

    The study is based on theory from innovation systems and strategic foresight. First, a review of literature was carried out and an innovation systems model of the FM sector was developed. Secondly, four national workshops were held involving FM practitioners and researchers from Denmark, Norway......, Sweden and Finland. Third, the results of the workshops were presented and discussed at a Nordic FM conference in August 2011. Finally, an adapted Delphi survey was carried out as a final data collection and validation of the findings. This article has the main focus on the results of the Delphi survey....

  1. Traditional protection ratios in FM sound broadcasting - still appropriate for interference management?

    Science.gov (United States)

    Philipp, J.

    2011-12-01

    A detailed analysis of the measurement procedures recommended by the International Telecommunication Union (ITU) shows that - with proper definition of audio quality - the FM broadcasting system can provide an audio signal-to-noise ratio of no better than 40 dB, when the interference in the neighboring channels exhausts the limits established by the internationally agreed protection ratios. Thus any attempt to relax the protection, be it motivated by the desire to implement additional FM or new digital services in the FM band, would inevitably degrade reception quality of existing services to levels hardly acceptable by broadcast listeners.

  2. Performance Analysis of FM-DCSK Communication System Based on Hyper Chaos%基于超混沌的FM-DCSK系统的性能分析

    Institute of Scientific and Technical Information of China (English)

    侯秀波; 张兴周; 李冰

    2007-01-01

    超混沌是高维的混沌系统,有2个以上正的Lyapunov指数,提出将其应用在FM-DCSK系统中,具有比低维混沌的FM-DCSK系统更为优良的保密性能以及较好的抗干扰能力.在信道噪声以及滤波器存在的条件下,通过理论分析和Matlab数值仿真,用误码率(BER)与信噪比(SNR)的关系刻画了基于超混沌的FM-DCSK调制系统的性能.实验结果表明了该方法的优越性.

  3. Ground penetrating radar mini-CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, R. [AlliedSignal, Inc., Kansas City, MO (United States). Federal Mfg. and Technologies; Stump, G. [Vermeer Mfg. Co. (United States); Weil, G. [EnTech Engineering, Inc. (United States)

    1996-09-01

    The purpose of this project was to determine the feasibility of using ground penetrating radar (GPR) to assess the ease of excavability prior to and during trenching operations. The project partners were EnTech Engineering Inc., Vermeer Manufacturing Co., and AlliedSignal Federal Manufacturing & Technology (FM&T)/Kansas City Plant (KCP). Commercial GPRs were field tested as well as a system developed at AlliedSignal FM&T. The AlliedSignal GPR was centered around a HP8753 Network Analyzer instrument. Commercial GPR antennas were connected to the analyzer and data was collected under control of software written for a notebook PC. Images of sub-surface features were generated for varied system parameters including: frequency, bandwidth, FFT windowing, gain, antenna orientation, and surface roughness conditions. Depths to 10 feet were of primary interest in this project. Although further development is required, this project has demonstrated that GPR can be used to identify transitions between different sub-surface conditions, as in going from one rock type to another. Additionally, the average relative dielectric constant of the material can be estimated which can be used to help identify the material. This information can be used to characterize an excavation site for use in budgeting a job. A real-time GPR would provide the operator with sub-surface images that could help with setting the optimum feed and speed rates of the trenching machine.

  4. Interdisciplinary Earth Science Applications Using Satellite Radar Altimetry

    Science.gov (United States)

    Kuo, C.; Shum, C.; Lee, H.; Dai, C.; Yi, Y.

    2012-12-01

    Satellite altimetry was conceived as a space geodetic concept for ocean surface topography mapping in the NASA-sponsored 1969 Williamstown, MA Conference, and was tested as part of the passive and active radar payload (S192), along with a radiometer and a scatterometer, on Skylab-1 in May 14, 1973. Since then, numerous radar and laser satellite altimetry missions orbiting/flying-by the Earth, Mars, Mercury, Titan and the Moon have been launched, evolving from the original scientific objective of marine gravity field mapping to a geodetic tool to address interdisciplinary Earth and planetary sciences. The accuracy of the radar altimeter has improved from 0.9 m RMS for the S-192 Skylab Ku-band compressed-pulse altimeter, to 2 cm RMS (2 second average) for the dual-frequency pulse-limited radar altimetry and associated sensors onboard TOPEX/POSEIDON. Satellite altimetry has evolved into a unique cross-disciplinary geodetic tool in addressing contemporary Earth science problems including sea-level rise, large-scale general ocean circulation, ice-sheet mass balance, terrestrial hydrology, and bathymetry. Here we provide a concise review and describe specific results on the additional recent innovative and unconventional applications of interdisciplinary science research using satellite radar altimetry, including geodynamics, land subsidence, snow depth, wetland and cold region hydrology.

  5. Removing interfering clutter associated with radar pulses that an airborne radar receives from a radar transponder

    Science.gov (United States)

    Ormesher, Richard C.; Axline, Robert M.

    2008-12-02

    Interfering clutter in radar pulses received by an airborne radar system from a radar transponder can be suppressed by developing a representation of the incoming echo-voltage time-series that permits the clutter associated with predetermined parts of the time-series to be estimated. These estimates can be used to estimate and suppress the clutter associated with other parts of the time-series.

  6. The effects of electric and magnetic fields on the current spin polarization and magnetoresistance in a ferromagnetic/organic semiconductor/ferromagnetic (FM/OSC/FM) system

    Institute of Scientific and Technical Information of China (English)

    Wang Yu-Mei; Ren Jun-Feng; Yuan Xiao-Bo; Dou Zhao-Tao; Hu Gui-Chao

    2012-01-01

    From experimental results of spin polarized injection and transport in organic semiconductors (OSCs),we theoretically study the current spin polarization and magnetoresistance under an electric and a magnetic field in a ferromagnetic/organic semiconductor/ferromagnetic (FM/OSC/FM) sandwich structure according to the spin drift-diffusion theory and Ohm's law.From the calculations,it is found that the interfacial current spin polarization is enhanced by several orders of magnitude through tuning the magnetic and electric fields by taking into account the specific characteristics of OSC.Furthermore,the effects of the electric and magnetic fields on the magnetoresistance are also discussed in the sandwich structure.

  7. Research on FM HD Radio System and Analysis on Coverage Interference%FM HD Radio系统研究及覆盖干扰分析

    Institute of Scientific and Technical Information of China (English)

    盛国芳; 曹元莉; 吴智勇; 万戈

    2010-01-01

    我国目前尚未推出调频广播数字化标准,HDRadio是美国调幅/调频波段的数字广播标准并在美国本土和世界各国进行了测试和推广.本文主要介绍了FM HD Radio传输系统的相关技术及其传输性能,并结合一些国外实验室的测试结果讨论FM HD Radio的覆盖和干扰问题.

  8. DESIGN AND DEVELOPMENT OF XBAND OSCILLATOR FOR FM TELEMETRY TRANSMITTER

    Directory of Open Access Journals (Sweden)

    S.SREEKANTH,

    2011-05-01

    Full Text Available Oscillator represents the basic microwave energy source for all microwave systems such as radar, communication and navigation. A typical oscillator essentially consist of an active device and passivefrequency determining resonant element such as dielectric resonator, micro strip resonator and tuned circuit for fixed frequency oscillators, varactor for tunable oscillators. The transistor used was fujitsu, FHX13LG, operating at DC bias of 2V and 25mA.The oscillator was designed using the 1/3 oscillation rule because of its effectiveness and simplicity. Oscillator feedback was connected to HEMT in a common source configuration using transmission line and capacitor. The emphasis has been on high power, low noise, small cost, high reliability and high temperature stability.Practical design aspects including the choice of transistor, negative feedback circuits, load coupling, low phase noise, quality factor and operation at the highest phase slope for minimum phase noise areincluded. This paper deals Design and Development of X band Oscillator for Telemetry Transmitter by using ADS simulation software and it has been designed at 8 GHz frequency.

  9. Using raindrop size distributions from different types of disdrometer to establish weather radar algorithms

    Science.gov (United States)

    Baldini, Luca; Adirosi, Elisa; Roberto, Nicoletta; Vulpiani, Gianfranco; Russo, Fabio; Napolitano, Francesco

    2015-04-01

    Radar precipitation retrieval uses several relationships that parameterize precipitation properties (like rainfall rate and liquid water content and attenuation (in case of radars at attenuated frequencies such as those at C- and X- band) as a function of combinations of radar measurements. The uncertainty in such relations highly affects the uncertainty precipitation and attenuation estimates. A commonly used method to derive such relationships is to apply regression methods to precipitation measurements and radar observables simulated from datasets of drop size distributions (DSD) using microphysical and electromagnetic assumptions. DSD datasets are determined both by theoretical considerations (i.e. based on the assumption that the radar always samples raindrops whose sizes follow a gamma distribution) or from experimental measurements collected throughout the years by disdrometers. In principle, using long-term disdrometer measurements provide parameterizations more representative of a specific climatology. However, instrumental errors, specific of a disdrometer, can affect the results. In this study, different weather radar algorithms resulting from DSDs collected by diverse types of disdrometers, namely 2D video disdrometer, first and second generation of OTT Parsivel laser disdrometer, and Thies Clima laser disdrometer, in the area of Rome (Italy) are presented and discussed to establish at what extent dual-polarization radar algorithms derived from experimental DSD datasets are influenced by the different error structure of the different type of disdrometers used to collect the data.

  10. Radar foundations for imaging and advanced concepts

    CERN Document Server

    Sullivan, Roger

    2004-01-01

    Through courses internally taught at IDA, Dr. Roger Sullivan has devised a book that brings readers fully up to speed on the most essential quantitave aspects of general radar in order to introduce study of the most exciting and relevant applications to radar imaging and advanced concepts: Synthetic Aperture Radar (4 chapters), Space-time Adaptive Processing, moving target indication (MTI), bistatic radar, low probability of intercept (LPI) radar, weather radar, and ground-penetrating radar. Whether you're a radar novice or experienced professional, this is an essential refer

  11. Broadview Radar Altimetry Toolbox

    Science.gov (United States)

    Mondéjar, Albert; Benveniste, Jérôme; Naeije, Marc; Escolà, Roger; Moyano, Gorka; Roca, Mònica; Terra-Homem, Miguel; Friaças, Ana; Martinho, Fernando; Schrama, Ernst; Ambrózio, Américo; Restano, Marco

    2016-07-01

    The universal altimetry toolbox, BRAT (Broadview Radar Altimetry Toolbox) which can read all previous and current altimetry missions' data, incorporates now the capability to read the upcoming Sentinel-3 L1 and L2 products. ESA endeavoured to develop and supply this capability to support the users of the future Sentinel-3 SAR Altimetry Mission. BRAT is a collection of tools and tutorial documents designed to facilitate the processing of radar altimetry data. This project started in 2005 from the joint efforts of ESA (European Space Agency) and CNES (Centre National d'Études Spatiales), and it is freely available at http://earth.esa.int/brat. The tools enable users to interact with the most common altimetry data formats. The BratGUI is the front-end for the powerful command line tools that are part of the BRAT suite. BRAT can also be used in conjunction with MATLAB/IDL (via reading routines) or in C/C++/Fortran via a programming API, allowing the user to obtain desired data, bypassing the data-formatting hassle. BRAT can be used simply to visualise data quickly, or to translate the data into other formats such as NetCDF, ASCII text files, KML (Google Earth) and raster images (JPEG, PNG, etc.). Several kinds of computations can be done within BRAT involving combinations of data fields that the user can save for posterior reuse or using the already embedded formulas that include the standard oceanographic altimetry formulas. The Radar Altimeter Tutorial, that contains a strong introduction to altimetry, shows its applications in different fields such as Oceanography, Cryosphere, Geodesy, Hydrology among others. Included are also "use cases", with step-by-step examples, on how to use the toolbox in the different contexts. The Sentinel-3 SAR Altimetry Toolbox shall benefit from the current BRAT version. While developing the toolbox we will revamp of the Graphical User Interface and provide, among other enhancements, support for reading the upcoming S3 datasets and

  12. The FM Market in the Nordic Countries – Volume, Structure and Trends

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2012-01-01

    The main purpose of this research is to give an overview of the FM market in Denmark, Norway, Sweden and Finland. A detailed study of the Danish FM market was done in 2008-9. This was followed up by a series of workshops facilitated by the author with groups of specialists in each of the countries...... in 2010 and 2011 to collect up-to-date information about all the 4 countries in relation to market volume, degree of outsourcing, structure and trends. The method for data collection was inspired by Delphi method. During the workshop the participants filled in a questionnaire with individual answers after...... about FM Market Data in Europe. In connection with the mentioned workshops another set of workshops were organized – except for Finland on the same day and with the same group of specialist – as part of a research project on FM Futures. The main purpose of this research is to provide input to a common...

  13. The Implementation of Performance Measurement System (PMS: Malaysian Facilities Management (FM Industry

    Directory of Open Access Journals (Sweden)

    Myeda N.E.

    2014-01-01

    Full Text Available Performance Measurement System (PMS is an effective performance measurement tool and technique that is being widely implemented in the global industries. Literature has suggested the significant contributions of its implementation in enhancing the strategic service delivery and performance. However, there is little study undertaken to explore the PMS implementation in Facilities Management (FM industry, particularly focusing on Malaysia. This study explores the PMS practice among FM practitioners and their knowledge in Performance Measurement (PM generally. Findings from this study also proposed the 20 contributing factors that the FM practitioners believed are the barriers in implementing PMS. This research also suggests the future research opportunities in developing a PMS framework that can be used as guidance for FM service delivery in Malaysia.

  14. Digital Demodulation Algorithm for Multi-Tone FM Signal in New Type Track Circuit

    Institute of Scientific and Technical Information of China (English)

    ZHU Lin-xiao; WU Si-liang

    2006-01-01

    The multi-tone frequency modulation (FM) signal transferred through track circuit in automatic train control (ATC) system is analyzed. A digital filter with ideal sloping shape in frequency domain is designed for frequency discrimination. With this filter, the FM signal is converted into AM-FM signal by frequency-to-amplitude conversion. The modulating signal is finally extracted from the envelope of the AM-FM signal. Simulations show that the digital demodulation method could accurately recover the modulating signal in low signal noise ratio (SNR) circumstance, and has good performance in suppressing interference of harmonics of traction current frequency. The feasibility of the proposed method is proved in a hardware system based on SHARC DSP.

  15. Qualitative analysis of am and fm screening in multicolor offset printing

    Directory of Open Access Journals (Sweden)

    Pašić Roberto

    2008-01-01

    Full Text Available This work is based on analysis and experimental verification with the aim to determine difference in several printing attributes, on AM and FM screenings at multicolor offset print.

  16. The FM Market in the Nordic Countries – Volume, Structure and Trends

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2012-01-01

    The main purpose of this research is to give an overview of the FM market in Denmark, Norway, Sweden and Finland. A detailed study of the Danish FM market was done in 2008-9. This was followed up by a series of workshops facilitated by the author with groups of specialists in each of the countries...... about FM Market Data in Europe. In connection with the mentioned workshops another set of workshops were organized – except for Finland on the same day and with the same group of specialist – as part of a research project on FM Futures. The main purpose of this research is to provide input to a common...... in 2010 and 2011 to collect up-to-date information about all the 4 countries in relation to market volume, degree of outsourcing, structure and trends. The method for data collection was inspired by Delphi method. During the workshop the participants filled in a questionnaire with individual answers after...

  17. 75 FR 47488 - FM Table of Allotments, Boulder Town, Levan, Mount Pleasant, and Richfield, UT

    Science.gov (United States)

    2010-08-06

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 FM Table of Allotments, Boulder Town, Levan, Mount Pleasant, and Richfield, UT AGENCY: Federal Communications Commission. ACTION: Final rule; petition for partial...

  18. Weather Radar Technology Development

    Science.gov (United States)

    1990-08-15

    Preparation). MISCELLANEOUS Donaldson Jr, R.J., 1987: "Significance of the 40th Anniversary Conference." Address at the Battan Memorial and 40th Anni - versary...Bergen and Albers (1987). They have achieved -37 -29 -25 -6 4 7 magnificent results for reducing general -35 -28 -19 -7 -3 4 ambiguity. 283 284 285 3.2... Albers , 1988: Two- and the National Severe Storms Laboratory S-band three-dimensional de-aliasing of Doppler radar in Norman, Oklahoma. For three

  19. Developing and integrating a computer-based AM/FM radio station

    Directory of Open Access Journals (Sweden)

    Everardo Inzunza González

    2010-06-01

    Full Text Available This article presents the development of a personal computer based AM/FM radio station operating on the AM/FM commercial band. Developing the graphical user interface for the software and the interconnection with an RF function generator by means of a GPIB is presented. Computer users can enter the desired transmission frequency within the commercial band as well as the transmission potency.

  20. Terahertz radar cross section measurements

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional radar...

  1. Performance indicators modern surveillance radar

    NARCIS (Netherlands)

    Nooij, P.N.C.; Theil, A.

    2014-01-01

    Blake chart computations are widely employed to rank detection coverage capabilities of competitive search radar systems. Developed for comparable 2D radar systems with a mechanically rotating reflector antenna, it was not necessary to regard update rate and plot quality in Blake's chart. To

  2. Measuring human behaviour with radar

    NARCIS (Netherlands)

    Dorp, Ph. van

    2001-01-01

    The paper presents human motion measurements with the experimental Frequency Modulated Continuous Wave(FMCW) radar at TNO-FEL. The aim of these measurements is to analyse the Doppler velocity spectrum of humans. These analysis give insight in measuring human behaviour with radar for security applica

  3. Behavior Subtraction applied to radar

    NARCIS (Netherlands)

    Rossum, W.L. van; Caro Cuenca, M.

    2014-01-01

    An algorithm developed for optical images has been applied to radar data. The algorithm, Behavior Subtraction, is based on capturing the dynamics of a scene and detecting anomalous behavior. The radar application is the detection of small surface targets at sea. The sea surface yields the expected s

  4. Imaging with Synthetic Aperture Radar

    CERN Document Server

    Massonnet, Didier

    2008-01-01

    Describing a field that has been transformed by the recent availability of data from a new generation of space and airborne systems, the authors offer a synthetic geometrical approach to the description of synthetic aperture radar, one that addresses physicists, radar specialists, as well as experts in image processing.  

  5. Performance indicators modern surveillance radar

    NARCIS (Netherlands)

    Nooij, P.N.C.; Theil, A.

    2014-01-01

    Blake chart computations are widely employed to rank detection coverage capabilities of competitive search radar systems. Developed for comparable 2D radar systems with a mechanically rotating reflector antenna, it was not necessary to regard update rate and plot quality in Blake's chart. To charact

  6. Synthetic Aperture Radar - Hardware Development

    Directory of Open Access Journals (Sweden)

    V. Rosner

    2009-06-01

    Full Text Available Experimental real and synthetic aperture radar are developed from the base-band digital unit to the analogue RF parts, based on solid state units, using pulse compression for radar imaging. Proper QPSK code is found for matched filter.

  7. Radar image registration and rectification

    Science.gov (United States)

    Naraghi, M.; Stromberg, W. D.

    1983-01-01

    Two techniques for radar image registration and rectification are presented. In the registration method, a general 2-D polynomial transform is defined to accomplish the geometric mapping from one image into the other. The degree and coefficients of the polynomial are obtained using an a priori found tiepoint data set. In the second part of the paper, a rectification procedure is developed that models the distortion present in the radar image in terms of the radar sensor's platform parameters and the topographic variations of the imaged scene. This model, the ephemeris data and the digital topographic data are then used in rectifying the radar image. The two techniques are then used in registering and rectifying two examples of radar imagery. Each method is discussed as to its benefits, shortcomings and registration accuracy.

  8. A radar image time series

    Science.gov (United States)

    Leberl, F.; Fuchs, H.; Ford, J. P.

    1981-01-01

    A set of ten side-looking radar images of a mining area in Arizona that were aquired over a period of 14 yr are studied to demonstrate the photogrammetric differential-rectification technique applied to radar images and to examine changes that occurred in the area over time. Five of the images are rectified by using ground control points and a digital height model taken from a map. Residual coordinate errors in ground control are reduced from several hundred meters in all cases to + or - 19 to 70 m. The contents of the radar images are compared with a Landsat image and with aerial photographs. Effects of radar system parameters on radar images are briefly reviewed.

  9. A radar backscattering mechanism of ocean surface in response to rainfall

    Science.gov (United States)

    Liu, Xinan; Zheng, Quanan; Liu, Ren; Duncan, James H.

    2012-11-01

    The characteristics of ocean surface in response to rainfall and its radar back-scatter are simultaneously measured in laboratory. The experiment is carried out in a water pool that is 1.22 m by 1.22 m with a water depth of 0.3 m. Artificial rainfall is generated from an array of hypodermic needles. The surface characteristics including crowns, stalks, secondary droplets and ring waves are measured with a cinematic Laser-Induced-Florescence (LIF) technique. Our experimental results show that impinging raindrops on the water surface generate various water surface structures with different relative sizes. Among them stalks and crowns comprise the dominant radar backscattering. On the basis of these laboratory experiments and theories of radar scattering from a rough surface, a near-resonance radar backscattering model for quantifying the dependence of the radar return intensity on rain rate on the ocean surface is developed. The model explains the radar response to rain rate simultaneously observed by C-band ASAR and ground-based weather radar. The physical model provides reasonable mechanisms to explain the frequency dependence and polarization behavior of radar signatures from rain cells on the ocean surface. This work is supported by the National Science Foundation, Division of Ocean Sciences under grant OCE962107.

  10. 100 years of radar

    CERN Document Server

    Galati, Gaspare

    2016-01-01

    This book offers fascinating insights into the key technical and scientific developments in the history of radar, from the first patent, taken out by Hülsmeyer in 1904, through to the present day. Landmark events are highlighted and fascinating insights provided into the exceptional people who made possible the progress in the field, including the scientists and technologists who worked independently and under strict secrecy in various countries across the world in the 1930s and the big businessmen who played an important role after World War II. The book encourages multiple levels of reading. The author is a leading radar researcher who is ideally placed to offer a technical/scientific perspective as well as a historical one. He has taken care to structure and write the book in such a way as to appeal to both non-specialists and experts. The book is not sponsored by any company or body, either formally or informally, and is therefore entirely unbiased. The text is enriched by approximately three hundred ima...

  11. Capturing atmospheric effects on 3D millimeter wave radar propagation patterns

    Science.gov (United States)

    Cook, Richard D.; Fiorino, Steven T.; Keefer, Kevin J.; Stringer, Jeremy

    2016-05-01

    Traditional radar propagation modeling is done using a path transmittance with little to no input for weather and atmospheric conditions. As radar advances into the millimeter wave (MMW) regime, atmospheric effects such as attenuation and refraction become more pronounced than at traditional radar wavelengths. The DoD High Energy Laser Joint Technology Offices High Energy Laser End-to-End Operational Simulation (HELEEOS) in combination with the Laser Environmental Effects Definition and Reference (LEEDR) code have shown great promise simulating atmospheric effects on laser propagation. Indeed, the LEEDR radiative transfer code has been validated in the UV through RF. Our research attempts to apply these models to characterize the far field radar pattern in three dimensions as a signal propagates from an antenna towards a point in space. Furthermore, we do so using realistic three dimensional atmospheric profiles. The results from these simulations are compared to those from traditional radar propagation software packages. In summary, a fast running method has been investigated which can be incorporated into computational models to enhance understanding and prediction of MMW propagation through various atmospheric and weather conditions.

  12. Ku-Band radar penetration into Snow over Arctic Sea Ice

    DEFF Research Database (Denmark)

    Hendricks, Stefan; Stenseng, Lars; Helm, Veit

    Sea ice freeboard measurements are of great interest for basin-scale ice mass balance monitoring. Typically, laser- and radar-altimeters are used for freeboard retrieval in operational systems such as aircrafts and satellites. For laser beams it can be assumed that the dominant reflector is the s......Sea ice freeboard measurements are of great interest for basin-scale ice mass balance monitoring. Typically, laser- and radar-altimeters are used for freeboard retrieval in operational systems such as aircrafts and satellites. For laser beams it can be assumed that the dominant reflector...... is the snow/air interface, whereas radar waves interact with the variable physical properties of the snow cover on the Arctic sea ice. In addition, radar elevation measurements may vary for different retracker algorithms, which determine the track point of the scattered echo power distribution. Since accurate...... knowledge of the reflection horizon is critical for sea ice thickness retrieval, validation data is necessary to investigate the penetration of radar waves into the snow for the upcoming CryoSat-2 mission. Furthermore, the combination of both optical and RF wavelengths might be used to derive snow thickness...

  13. International conference on Functional Materials and Nanotechnologies (FM&NT-2013), 21-24 April 2013, Tartu, Estonia

    Science.gov (United States)

    Nõmmiste, Ergo; Kirm, Marco; Plank, Toomas

    2014-04-01

    The annual international conference Functional Materials and Nanotechnologies (FM&NT) was started in 2006 by scientists from the Institute of Solid State Physics, University of Latvia. The warm welcome and open atmosphere of this scientific conference has turned it into an event where people from different countries and different fields come and meet under the shared umbrella of functional materials and nanotechnology. It is particularly important for early stage scientists who are looking for new knowledge and contacts with people from various fields to build their own network. Our Latvian colleagues, with their success in internationalization, made us neighbouring Estonians so jealous that we could not help but propose organising the conference every second year in Estonia. In a way, this conference is a continuation of the idea of the famous Baltic seminars which took place over several decades in the last century. Due to political constraints, these seminars were only open to scientists of former Eastern Europe countries, but had a great popularity and attendance from over the whole Soviet Union. Many collaborations started from the initial personal contact between scientists at these twice yearly seminars, held alternately in Latvia and Estonia. At the FM&NT 2012 conference, the decision was made that Institute of Physics, University of Tartu would organise the next event in Tartu in 2013. FM&NT-2013 was hence held in Tartu (Estonia) from 21-24 April 2013 at the Dorpat Conference Centre. The main selected topics of the conference were: (i) multifunctional materials, (ii) nanomaterials, (iii) materials for sustainable energy applications and (vi) theory. Additionally, the focus in this conference was on studies with the help of synchrotron radiation and other novel light sources such as free electron lasers. The conference provided an opportunity for 300 scientists from 21 countries to meet, establish contacts, exchange knowledge and discuss their research

  14. Multi-Frequency Target Detection Techniques for DVB-T Based Passive Radar Sensors

    Directory of Open Access Journals (Sweden)

    Tatiana Martelli

    2016-09-01

    Full Text Available This paper investigates the possibility to improve target detection capability in a DVB-T- based passive radar sensor by jointly exploiting multiple digital television channels broadcast by the same transmitter of opportunity. Based on the remarkable results obtained by such a multi-frequency approach using other signals of opportunity (i.e., FM radio broadcast transmissions, we propose appropriate modifications to the previously devised signal processing techniques for them to be effective in the newly considered scenarios. The resulting processing schemes are extensively applied against experimental DVB-T-based passive radar data pertaining to different surveillance applications. The obtained results clearly show the effectiveness of the proposed multi-frequency approaches and demonstrate their suitability for application in the considered scenarios.

  15. Coherent laser vision system

    Energy Technology Data Exchange (ETDEWEB)

    Sebastion, R.L. [Coleman Research Corp., Springfield, VA (United States)

    1995-10-01

    The Coherent Laser Vision System (CLVS) is being developed to provide precision real-time 3D world views to support site characterization and robotic operations and during facilities Decontamination and Decommissioning. Autonomous or semiautonomous robotic operations requires an accurate, up-to-date 3D world view. Existing technologies for real-time 3D imaging, such as AM laser radar, have limited accuracy at significant ranges and have variability in range estimates caused by lighting or surface shading. Recent advances in fiber optic component technology and digital processing components have enabled the development of a new 3D vision system based upon a fiber optic FMCW coherent laser radar. The approach includes a compact scanner with no-moving parts capable of randomly addressing all pixels. The system maintains the immunity to lighting and surface shading conditions which is characteristic to coherent laser radar. The random pixel addressability allows concentration of scanning and processing on the active areas of a scene, as is done by the human eye-brain system.

  16. Radar signature acquisition using an indigenously designed noise radar system

    Science.gov (United States)

    Freundorfer, A. P.; Siddiqui, J. Y.; Antar, Y. M. M.; Thayaparan, T.

    2011-06-01

    A new design of a noise radar system is proposed with capabilities to measure and acquire the radar signature of various targets. The proposed system can cover a noise bandwidth of near DC to 30 GHz. The noise radar signature measurements were conducted for selective targets like spheres and carpenter squares with and without dielectric bodies for a noise band of 400MHz-3000MHz. The bandwidth of operation was limited by the multiplier and the antennae used. The measured results of the target signatures were verified with the simulation results.

  17. The use of radar for bathymetry assessment

    NARCIS (Netherlands)

    Aardoom, J.H.; Greidanus, H.S.F.

    1998-01-01

    The bottom topography in shallow seas can be observed by air- and spaceborne imaging radar. Bathymetric information derived from radar data is limited in accuracy, but radar has a good spatial coverage. The accuracy can be increased by assimilating the radar imagery into existing or insitu gathered

  18. Radar, Insect Population Ecology, and Pest Management

    Science.gov (United States)

    Vaughn, C. R. (Editor); Wolf, W. (Editor); Klassen, W. (Editor)

    1979-01-01

    Discussions included: (1) the potential role of radar in insect ecology studies and pest management; (2) the potential role of radar in correlating atmospheric phenomena with insect movement; (3) the present and future radar systems; (4) program objectives required to adapt radar to insect ecology studies and pest management; and (5) the specific action items to achieve the objectives.

  19. The use of radar for bathymetry assessment

    NARCIS (Netherlands)

    Aardoom, J.H.; Greidanus, H.S.F.

    1998-01-01

    The bottom topography in shallow seas can be observed by air- and spaceborne imaging radar. Bathymetric information derived from radar data is limited in accuracy, but radar has a good spatial coverage. The accuracy can be increased by assimilating the radar imagery into existing or insitu gathered

  20. Radar signal analysis and processing using Matlab

    CERN Document Server

    Mahafza, Bassem R

    2008-01-01

    Offering radar-related software for the analysis and design of radar waveform and signal processing, this book provides comprehensive coverage of radar signals and signal processing techniques and algorithms. It contains numerous graphical plots, common radar-related functions, table format outputs, and end-of-chapter problems. The complete set of MATLAB[registered] functions and routines are available for download online.

  1. Large phased-array radars

    Science.gov (United States)

    Brookner, Eli, Dr.

    1988-12-01

    Large phased-array radars can play a very important part in arms control. They can be used to determine the number of RVs being deployed, the type of targeting of the RVs (the same or different targets), the shape of the deployed objects, and possibly the weight and yields of the deployed RVs. They can provide this information at night as well as during the day and during rain and cloud covered conditions. The radar can be on the ground, on a ship, in an airplane, or space-borne. Airborne and space-borne radars can provide high resolution map images of the ground for reconnaissance, of anti-ballistic missile (ABM) ground radar installations, missile launch sites, and tactical targets such as trucks and tanks. The large ground based radars can have microwave carrier frequencies or be at HF (high frequency). For a ground-based HF radar the signal is reflected off the ionosphere so as to provide over-the-horizon (OTH) viewing of targets. OTH radars can potentially be used to monitor stealth targets and missile traffic.

  2. Air and spaceborne radar systems an introduction

    CERN Document Server

    Lacomme, Philippe; Hardange, Jean-Philippe; Normant, Eric

    2001-01-01

    A practical tool on radar systems that will be of major help to technicians, student engineers and engineers working in industry and in radar research and development. The many users of radar as well as systems engineers and designers will also find it highly useful. Also of interest to pilots and flight engineers and military command personnel and military contractors. """"This introduction to the field of radar is intended for actual users of radar. It focuses on the history, main principles, functions, modes, properties and specific nature of modern airborne radar. The book examines radar's

  3. Signal processing in noise waveform radar

    CERN Document Server

    Kulpa, Krzysztof

    2013-01-01

    This book is devoted to the emerging technology of noise waveform radar and its signal processing aspects. It is a new kind of radar, which use noise-like waveform to illuminate the target. The book includes an introduction to basic radar theory, starting from classical pulse radar, signal compression, and wave radar. The book then discusses the properties, difficulties and potential of noise radar systems, primarily for low-power and short-range civil applications. The contribution of modern signal processing techniques to making noise radar practical are emphasized, and application examples

  4. Under the Radar

    CERN Document Server

    Goss, WM

    2010-01-01

    This is the biography of Ruby Payne-Scott (1912 to 1981). As the first female radio astronomer (and one of the first people in the world to consider radio astronomy), she made classic contributions to solar radio physics. She also played a major role in the design of the Australian government's Council for Scientific and Industrial Research radars, which were in turn of vital importance in the Southwest Pacific Theatre in World War II and were used by Australian, US and New Zealand personnel. From a sociological perspective, her career also offers many examples of the perils of being a female academic in the first half of the 20th century. Written in an engaging style and complemented by many historical photographs this book gives a fascinating insight into the beginning of radio astronomy and the role of a pioneering woman in astronomy.

  5. Gyroklystron-Powered WARLOC Radar

    Science.gov (United States)

    Danly, B. G.; Cheung, W. J.; Gregers-Hansen, V.; Linde, G.; Ngo, M.

    2003-12-01

    A high-power, coherent, W-band (94 GHz) millimeter-wave radar has been developed at the Naval Research Laboratory. This radar, named WARLOC, employs a 100 kW peak power, 10 kW average power gyro-klystron as the final power amplifier, an overmoded transmission line system, and a quasi-optical duplexer, together with a high gain antenna, four-channel receiver, and state-of-the-art signal processing. The gyro-amplifiers and the implementation in the WARLOC radar will be described.

  6. 77 HHz radar for automobile

    Directory of Open Access Journals (Sweden)

    O. M. Lyashuk

    2012-02-01

    Full Text Available Modern requirements to safety and comfort of drivers and passengers of a car cause continuous development of corresponding technical facilities. Technologies that provide implementation of these requirements are on the first place for the developers of cars. One of the most important requirement is an analysis of road situation, where various sensors are used. One of them is radar. Principle of action, basic parameters and application of radar RS-200 is considered in this article. Radar is used in modern cars of brand Mersedes Benz and works on frequency 77 HHz. It uses the LFM (linear frequency modulation with the programmatic setting of resolution for distance.

  7. Introduction to radar target recognition

    CERN Document Server

    Tait, P

    2006-01-01

    This new text provides an overview of the radar target recognition process and covers the key techniques being developed for operational systems. It is based on the fundamental scientific principles of high resolution radar, and explains how the techniques can be used in real systems, taking into account the characteristics of practical radar system designs and component limitations. It also addresses operational aspects, such as how high resolution modes would fit in with other functions such as detection and tracking. Mathematics is kept to a minimum and the complex techniques and issues are

  8. Space noise synthetic aperture radar

    Science.gov (United States)

    Kulpa, Krzysztof S.

    2006-03-01

    The paper presents limitations of space borne synthetic aperture radars, caused by range and Doppler velocity ambiguities, and the concept of usage of the noise radar technology for creation of high-resolution space SAR images. The noise SAR is free from limitation caused by the periodicity of pulse waveform ambiguity function, and therefore this technology can be used in the future space missions. The basic concept of noise SAR image formation is also presented. The image formation algorithm has been verified using the simulated data produced by Raw Radar Data Simulator.

  9. Coordinated Radar Resource Management for Networked Phased Array Radars

    Science.gov (United States)

    2014-12-01

    computed, and the detection of a target is determined based on a Monte Carlo test. For each successful target confirmation, a measurement report is...detection based on Monte Carlo test • add appropriate random perturbations to detec- tion measurements Radar Targets Environment Input Parameters... Fuente and J.R. Casar-Corredera. Optimal radar pulse scheduling using a neural network. In IEEE Int. Conf. Neural Networks, volume 7, pages 4558–4591

  10. A Pilot Investigation regarding Speech-Recognition Performance in Noise for Adults with Hearing Loss in the FM+HA Listening Condition

    Science.gov (United States)

    Lewis, M. Samantha; Gallun, Frederick J.; Gordon, Jane; Lilly, David J.; Crandell, Carl

    2010-01-01

    While the concurrent use of the hearing aid (HA) microphone with frequency modulation (FM) technology can decrease speech-recognition performance, the FM+HA condition is still an important setting for users of both HA and FM technology. The primary goal of this investigation was to evaluate the effect of attenuating HA gain in the FM+HA listening…

  11. The stray capacitance effect in Kelvin probe force microscopy using FM, AM and heterodyne AM modes.

    Science.gov (United States)

    Ma, Zong Min; Kou, Lili; Naitoh, Yoshitaka; Li, Yan Jun; Sugawara, Yasuhiro

    2013-06-07

    The effect of stray capacitance on potential measurements was investigated using Kelvin probe force microscopy (KPFM) at room temperature under ultra-high vacuum (UHV). The stray capacitance effect was explored in three modes, including frequency modulation (FM), amplitude modulation (AM) and heterodyne amplitude modulation (heterodyne AM). We showed theoretically that the distance-dependence of the modulated electrostatic force in AM-KPFM is significantly weaker than in FM- and heterodyne AM-KPFMs and that the stray capacitance of the cantilever, which seriously influences the potential measurements in AM-KPFM, was almost completely eliminated in FM- and heterodyne AM-KPFMs. We experimentally confirmed that the contact potential difference (CPD) in AM-KPFM, which compensates the electrostatic force between the tip and the surface, was significantly larger than in FM- and heterodyne AM-KPFMs due to the stray capacitance effect. We also compared the atomic scale corrugations in the local contact potential difference (LCPD) among the three modes on the surface of Si(111)-7 × 7 finding that the LCPD corrugation in AM-KPFM was significantly weaker than in FM- and heterodyne AM-KPFMs under low AC bias voltage conditions. The very weak LCPD corrugation in AM-KPFM was attributed to the artefact induced by topographic feedback.

  12. The laser and its uses: 50 years after its invention; Le laser et ses applications: 50 ans apres son invention

    Energy Technology Data Exchange (ETDEWEB)

    Besnard, P. [FOTON/ENSSAT, CNRS, 22 - Lannion (France); Favennec, P.N. [APAST, 22 - Lannion (France)

    2011-07-01

    The laser, 50 years after its invention, has become a major player in modern technologies with its efficient partner the optical fiber. This book reviews the numerous applications of laser in diverse fields such as telecommunication, metrology, optical radar, surface treatment, medicine. The last chapter is dedicated to inertial fusion through the presentation of the Megajoule laser (LMJ) project

  13. Compressive Sensing for MIMO Radar

    CERN Document Server

    Yu, Yao; Poor, H Vincent

    2009-01-01

    Multiple-input multiple-output (MIMO) radar systems have been shown to achieve superior resolution as compared to traditional radar systems with the same number of transmit and receive antennas. This paper considers a distributed MIMO radar scenario, in which each transmit element is a node in a wireless network, and investigates the use of compressive sampling for direction-of-arrival (DOA) estimation. According to the theory of compressive sampling, a signal that is sparse in some domain can be recovered based on far fewer samples than required by the Nyquist sampling theorem. The DOA of targets form a sparse vector in the angle space, and therefore, compressive sampling can be applied for DOA estimation. The proposed approach achieves the superior resolution of MIMO radar with far fewer samples than other approaches. This is particularly useful in a distributed scenario, in which the results at each receive node need to be transmitted to a fusion center for further processing.

  14. Air Defense Radar Operations Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Facility consists of laboratories, experimental test equipment including state-of-theart test bed radar, and test ranges. The facilities are used to design, develop,...

  15. Air Defense Radar Operations Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Facility consists of laboratories, experimental test equipment including state-of-theart test bed radar, and test ranges. The facilities are used to design, develop,...

  16. SMAP RADAR Calibration and Validation

    Science.gov (United States)

    West, R. D.; Jaruwatanadilok, S.; Chaubel, M. J.; Spencer, M.; Chan, S. F.; Chen, C. W.; Fore, A.

    2015-12-01

    The Soil Moisture Active Passive (SMAP) mission launched on Jan 31, 2015. The mission employs L-band radar and radiometer measurements to estimate soil moisture with 4% volumetric accuracy at a resolution of 10 km, and freeze-thaw state at a resolution of 1-3 km. Immediately following launch, there was a three month instrument checkout period, followed by six months of level 1 (L1) calibration and validation. In this presentation, we will discuss the calibration and validation activities and results for the L1 radar data. Early SMAP radar data were used to check commanded timing parameters, and to work out issues in the low- and high-resolution radar processors. From April 3-13 the radar collected receive only mode data to conduct a survey of RFI sources. Analysis of the RFI environment led to a preferred operating frequency. The RFI survey data were also used to validate noise subtraction and scaling operations in the radar processors. Normal radar operations resumed on April 13. All radar data were examined closely for image quality and calibration issues which led to improvements in the radar data products for the beta release at the end of July. Radar data were used to determine and correct for small biases in the reported spacecraft attitude. Geo-location was validated against coastline positions and the known positions of corner reflectors. Residual errors at the time of the beta release are about 350 m. Intra-swath biases in the high-resolution backscatter images are reduced to less than 0.3 dB for all polarizations. Radiometric cross-calibration with Aquarius was performed using areas of the Amazon rain forest. Cross-calibration was also examined using ocean data from the low-resolution processor and comparing with the Aquarius wind model function. Using all a-priori calibration constants provided good results with co-polarized measurements matching to better than 1 dB, and cross-polarized measurements matching to about 1 dB in the beta release. During the

  17. Haystack Ultrawideband Satellite Imaging Radar

    Science.gov (United States)

    2014-09-01

    enable long-range imaging. In 2013, a major upgrade to the facility was completed, adding a millimeter - wave W-band radar capability to Haystack’s X...diameter antenna was completely rebuilt to provide a 100 μm root-mean-square (rms) surface accuracy to support operation at the 3 mm wave - length (W...electromagnetic wave propagation through the troposphere. − The signal processing system lev- eraged Lincoln Laboratory‘s Radar Open Systems

  18. Alternatives for Military Space Radar

    Science.gov (United States)

    2007-01-01

    Because the characteristics and performance of Discov- erer II’s radar are well documented, CBO based the design of its notional Space Radar on that of...2005, report to accompany H.R. 4613, Report 108-553 (June 18, 2004). 13. Air Force Space and Missile Systems Center, “Fact Sheet: Discov- erer II...360-degree coverage in GMTI mode. See Federation of American Scientists, Space Policy Project, “Discov- erer II STARLITE” (January 24, 2000

  19. Coded continuous wave meteor radar

    Science.gov (United States)

    Chau, J. L.; Vierinen, J.; Pfeffer, N.; Clahsen, M.; Stober, G.

    2016-12-01

    The concept of a coded continuous wave specular meteor radar (SMR) is described. The radar uses a continuously transmitted pseudorandom phase-modulated waveform, which has several advantages compared to conventional pulsed SMRs. The coding avoids range and Doppler aliasing, which are in some cases problematic with pulsed radars. Continuous transmissions maximize pulse compression gain, allowing operation at lower peak power than a pulsed system. With continuous coding, the temporal and spectral resolution are not dependent on the transmit waveform and they can be fairly flexibly changed after performing a measurement. The low signal-to-noise ratio before pulse compression, combined with independent pseudorandom transmit waveforms, allows multiple geographically separated transmitters to be used in the same frequency band simultaneously without significantly interfering with each other. Because the same frequency band can be used by multiple transmitters, the same interferometric receiver antennas can be used to receive multiple transmitters at the same time. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large-scale multi-static network of meteor radar transmitters and receivers. Such a system would be useful for increasing the number of meteor detections to obtain improved meteor radar data products, such as wind fields. This type of a radar would also be useful for over-the-horizon radar, ionosondes, and observations of field-aligned-irregularities.

  20. Radar Imaging and Target Identification

    Science.gov (United States)

    2009-02-09

    Methods in Wave Propagation, Vaxjo, Swe- den. • February 19, 2008, "Radar Imaging", math colloquium, Brigham- Young University. • January 31, 2008...manuscript, namely "Radar detection using sparsely distributed 19 apertures in urban environments", Ling Wang, II- Young Son, Trond Varslot, C. Evren...Coinmun. COM- 20, pp. 774-780, 1972. [24] M. Tomlinson, "New automatic equalizer employing modulo arithmetic," Electron. Lett. 7, pp. 138-139, 1971

  1. Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR)

    Science.gov (United States)

    2013-06-01

    performance in complex scenarios. Among these scenarios are ground penetrating radar and forward-looking radar for landmine and improvised explosive...Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR) by Traian Dogaru ARL-TN-0548 June 2013...2013 Model-Based Radar Power Calculations for Ultra-Wideband (UWB) Synthetic Aperture Radar (SAR) Traian Dogaru Sensors and Electron

  2. Radar TopoMapper concept for planetary exploration

    Science.gov (United States)

    Madsen, Soren N.; Lou, Yun-Ling; Hensley, Scott; Harvey, Wayne L.; McKinnon, William B.

    2004-12-01

    Topographic information is key to interpreting the geology and geophysics of planetary bodies such as the icy Galilean satellites. Traditionally elevation information has been derived from stereo-photogrammetry, but the last couple of decades have offered new techniques, including radar interferometry, photoclinometry (shape from shading) and laser altimetry. Combining synthetic aperture radar (SAR) technology with interferometry (InSAR) enables high resolution imaging with elevation information at each image point. With two appropriately spaced antennas on a spacecraft, single-pass imaging radar interferometry can provide wide swath topographic data, independent of solar illumination, as was recently demonstrated on Earth by the Shuttle Topographic Radar Mission (SRTM; www.jpl.nasa.gov/srtm). We will present the science requirements, measurement principle, a straw-man"s design, and the predicted performance of a "compact SRTM" which could be flown on NASA missions such as the proposed Jupiter Icy Moons Orbiter (JIMO). In this paper we discuss challenges, including the calibration strategy and critical technology elements such as the high power RF-amplifier. We expect that the performance, both in terms of elevation accuracy and mapping rate would suffice to 1) determine topography on local and regional scales; 2) search for active geological change on the time scale of JIMO"s orbit around, e.g., Europa (30-60 days); and 3) determine the global tidal amplitude at Europa, Callisto, and Ganymede, which would constitute direct proof of the existence of oceans in all three icy moons.

  3. Laser sources for lidar applications

    Science.gov (United States)

    Kilmer, J.; Iadevaia, A.; Yin, Y.

    2012-06-01

    Advanced LIDAR applications such as next gen: Micro Pulse; Time of Flight (e.g., Satellite Laser Ranging); Coherent and Incoherent Doppler (e.g., Wind LIDAR); High Spectral Resolution; Differential Absorption (DIAL); photon counting LIDAR (e.g., 3D LIDAR); are placing more demanding requirements on conventional lasers (e.g., increased rep rates, etc.) and have inspired the development of new types of laser sources. Today, solid state lasers are used for wind sensing, 2D laser Radar, 3D scanning and flash LIDAR. In this paper, we report on the development of compact, highly efficient, high power all-solidstate diode pulsed pumped ns lasers, as well as, high average power/high pulse energy sub nanosecond (picosecond (lasers for these next gen LIDAR applications.

  4. Coded continuous wave meteor radar

    Science.gov (United States)

    Vierinen, Juha; Chau, Jorge L.; Pfeffer, Nico; Clahsen, Matthias; Stober, Gunter

    2016-03-01

    The concept of a coded continuous wave specular meteor radar (SMR) is described. The radar uses a continuously transmitted pseudorandom phase-modulated waveform, which has several advantages compared to conventional pulsed SMRs. The coding avoids range and Doppler aliasing, which are in some cases problematic with pulsed radars. Continuous transmissions maximize pulse compression gain, allowing operation at lower peak power than a pulsed system. With continuous coding, the temporal and spectral resolution are not dependent on the transmit waveform and they can be fairly flexibly changed after performing a measurement. The low signal-to-noise ratio before pulse compression, combined with independent pseudorandom transmit waveforms, allows multiple geographically separated transmitters to be used in the same frequency band simultaneously without significantly interfering with each other. Because the same frequency band can be used by multiple transmitters, the same interferometric receiver antennas can be used to receive multiple transmitters at the same time. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large-scale multi-static network of meteor radar transmitters and receivers. Such a system would be useful for increasing the number of meteor detections to obtain improved meteor radar data products.

  5. Value co-creation for FM innovation: Is it possible, and if yes, how?

    DEFF Research Database (Denmark)

    Nardelli, Giulia

    2017-01-01

    -1 definition, FM is “the integration of processes within an organization to maintain and develop (…) services which support and improve the effectiveness of its primary activities”. In other words, FM is expected to create value for the organization it belongs to, by at least delivering and maintaining......No matter the industry, co-creation of value is a hot topic. Marketing specialists swear by it; manufacturers and service providers try to integrate it in their innovation practices; researchers study it. But what is value co-creation, and how does it apply to FM? Value co-creation is grounded...... in the recognition that firms are no longer in full charge of deciding upon the value to be offered to markets, but rather need to continuously cooperate with their customers, who become active collaborators in the creation of value. Value, in fact, is jointly created by supply and demand. The former offer the frame...

  6. Eastward traverse of equatorial plasma plumes observed with the Equatorial Atmosphere Radar in Indonesia

    Directory of Open Access Journals (Sweden)

    S. Fukao

    2006-07-01

    Full Text Available The zonal structure of radar backscatter plumes associated with Equatorial Spread F (ESF, probably modulated by atmospheric gravity waves, has been investigated with the Equatorial Atmosphere Radar (EAR in West Sumatra, Indonesia (0.20° S, 100.32° E; dip latitude 10.1° S and the FM-CW ionospheric sounders on the same magnetic meridian as the EAR. The occurrence locations and zonal distances of the ESF plumes were determined with multi-beam observations with the EAR. The ESF plumes drifted eastward while keeping distances of several hundred to a thousand kilometers. Comparing the occurrence of the plumes and the F-layer uplift measured by the FM-CW sounders, plumes were initiated within the scanned area around sunset only, when the F-layer altitude rapidly increased. Therefore, the PreReversal Enhancement (PRE is considered as having a zonal variation with the scales mentioned above, and this variation causes day-to-day variability, which has been studied for a long time. Modulation of the underlying E-region conductivity by gravity waves, which causes inhomogeneous sporadic-E layers, for example, is a likely mechanism to determine the scale of the PRE.

  7. Eastward traverse of equatorial plasma plumes observed with the Equatorial Atmosphere Radar in Indonesia

    Science.gov (United States)

    Fukao, S.; Yokoyama, T.; Tayama, T.; Yamamoto, M.; Maruyama, T.; Saito, S.

    2006-07-01

    The zonal structure of radar backscatter plumes associated with Equatorial Spread F (ESF), probably modulated by atmospheric gravity waves, has been investigated with the Equatorial Atmosphere Radar (EAR) in West Sumatra, Indonesia (0.20° S, 100.32° E; dip latitude 10.1° S) and the FM-CW ionospheric sounders on the same magnetic meridian as the EAR. The occurrence locations and zonal distances of the ESF plumes were determined with multi-beam observations with the EAR. The ESF plumes drifted eastward while keeping distances of several hundred to a thousand kilometers. Comparing the occurrence of the plumes and the F-layer uplift measured by the FM-CW sounders, plumes were initiated within the scanned area around sunset only, when the F-layer altitude rapidly increased. Therefore, the PreReversal Enhancement (PRE) is considered as having a zonal variation with the scales mentioned above, and this variation causes day-to-day variability, which has been studied for a long time. Modulation of the underlying E-region conductivity by gravity waves, which causes inhomogeneous sporadic-E layers, for example, is a likely mechanism to determine the scale of the PRE.

  8. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM3_Edition1-CV)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  9. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM2_Edition1)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  10. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM1_Edition1-CV)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  11. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM4_Edition1)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-04-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  12. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM3_Edition2)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  13. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM2_Edition1-CV)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  14. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM4_Edition1-CV)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-03-30] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  15. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM3_Edition1)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  16. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM1_Edition2)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  17. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM1_Edition1)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-11-02] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  18. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Terra-FM2_Edition2)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2006-01-01] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  19. CERES BiDirectional Scans (BDS) data in HDF (CER_BDS_Aqua-FM4_Edition2)

    Science.gov (United States)

    Wielicki, Bruce A. (Principal Investigator)

    Each BiDirectional Scans (BDS) data product contains twenty-four hours of Level-1b data for each CERES scanner instrument mounted on each spacecraft. The BDS includes samples taken in normal and short Earth scan elevation profiles in both fixed and rotating azimuth scan modes (including space, internal calibration, and solar calibration views). The BDS contains Level-0 raw (unconverted) science and instrument data as well as the geolocated converted science and instrument data. The BDS contains additional data not found in the Level-0 input file, including converted satellite position and velocity data, celestial data, converted digital status data, and parameters used in the radiance count conversion equations. The following CERES BDS data sets are currently available: CER_BDS_TRMM-PFM_Edition1 CER_BDS_Terra-FM1_Edition1 CER_BDS_Terra-FM2_Edition1 CER_BDS_Terra-FM1_Edition2 CER_BDS_Terra-FM2_Edition2 CER_BDS_Aqua-FM3_Edition1 CER_BDS_Aqua-FM4_Edition1 CER_BDS_Aqua-FM3_Edition2 CER_BDS_Aqua-FM4_Edition2 CER_BDS_Aqua-FM3_Edition1-CV CER_BDS_Aqua-FM4_Edition1-CV CER_BDS_Terra-FM1_Edition1-CV CER_BDS_Terra-FM2_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  20. Multifrequency radar imaging of ash plumes: an experiment at Stromboli

    Science.gov (United States)

    Donnadieu, Franck; Freret-Lorgeril, Valentin; Delanoë, Julien; Vinson, Jean-Paul; Peyrin, Frédéric; Hervier, Claude; Caudoux, Christophe; Van Baelen, Joël; Latchimy, Thierry

    2016-04-01

    the beam, providing additional constraints on particle sizes and sedimentation process from ash clouds. Furthermore, proximal deposits were analyzed by sieving samples collected near the craters and processing data from a laser disdrometer. Ash samples constantly show a unimodal distribution ranging from 44 microns to 1 mm (more rarely 2 mm), with a mode in the range 0.1-0.3 mm. This is expected to be representative of the coarse content of the ash plumes generated by Strombolian explosions at Stromboli, i.e. mainly coarse ash, and will be used to constrain inversions of the radar signals.

  1. Thrombostatin FM compounds: direct thrombin inhibitors - mechanism of action in vitro and in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Nieman, M T; Burke, F; Warnock, M; Zhou, Y; Sweigart, J; Chen, A; Ricketts, D; Lucchesi, B R; Chen, Z; Cera, E Di; Hilfinger, J; Kim, J S; Mosberg, H I; Schmaier, A H [Case Western; (Michigan); (TSRL); (WU-MED)

    2008-04-29

    Novel pentapeptides called Thrombostatin FM compounds consisting mostly of D-isomers and unusual amino acids were prepared based upon the stable angiotensin converting enzyme breakdown product of bradykinin - RPPGF. These peptides are direct thrombin inhibitors prolonging the thrombin clotting time, activated partial thromboplastin time, and prothrombin time at ≥0.78, 1.6, and 1.6 μm, respectively. They competitively inhibit α-thrombin-induced cleavage of a chromogenic substrate at 4.4--8.2 μm. They do not significantly inhibit plasma kallikrein, factor (F) XIIa, FXIa, FIXa, FVIIa-TF, FXa, plasmin or cathepsin G. One form, FM19 [rOicPaF(p-Me)], blocks α-thrombin-induced calcium flux in fibroblasts with an IC50 of 6.9 ± 1.2 μm. FM19 achieved 100% inhibition of threshold α- or γ-thrombin-induced platelet aggregation at 8.4 ± 4.7 μm and 16 ± 4 μm, respectively. The crystal structure of thrombin in complex with FM19 shows that the N-terminal D-Arg retrobinds into the S1 pocket, its second residue Oic interacts with His-57, Tyr-60a and Trp-60d, and its C-terminal p-methyl Phe engages thrombin's aryl binding site composed of Ile-174, Trp-215, and Leu-99. When administered intraperitoneal, intraduodenal, or orally to mice, FM19 prolongs thrombin clotting times and delays carotid artery thrombosis. FM19, a low affinity reversible direct thrombin inhibitor, might be useful as an add-on agent to address an unmet need in platelet inhibition in acute coronary syndromes in diabetics and others who with all current antiplatelet therapy still have reactive platelets.

  2. The effect of water on the thermal expansion behavior of FM5055 carbon phenolic

    Science.gov (United States)

    Sullivan, Roy M.

    1995-01-01

    The effect of water on the thermal expansion behavior of FM5055 carbon phenolic is studied using a theory of mixtures approach. A partial pressure expression for the water constituent was obtained based upon certain assumptions regarding the thermodynamic state of water as it resides in the free volumes of the polymer. A simple constitutive model is used to simulate the polymer strain due to the application of the partial pressure of water. The resulting theory is applied to model the effect of moisture on the thermal expansion of FM5055 carbon phenolic specimens. The application of the theory results in calculated strains which were in close agreement with the measured strains.

  3. High Resolution Pulse Compression Imaging Using Super Resolution FM-Chirp Correlation Method (SCM)

    Science.gov (United States)

    Fujiwara, M.; Okubo, K.; Tagawa, N.

    This study addresses the issue of the super-resolution pulse compression technique (PCT) for ultrasound imaging. Time resolution of multiple ultrasonic echoes using the FM-Chirp PCT is limited by the bandwidth of the sweep-frequency. That is, the resolution depends on the sharpness of auto-correlation function. We propose the Super resolution FM-Chirp correlation Method (SCM) and evaluate its performance. This method is based on the multiple signal classification (MUSIC) algorithm. Our simulations were made for the model assuming multiple signals reflected from some scatterers. We confirmed that SCM detects time delay of complicated reflected signals successfully with high resolution.

  4. Performance of quasi-optimum digital FM demodulators for fading channels

    Science.gov (United States)

    Dharamsi, M. T.; Gupta, S. C.

    1975-01-01

    This paper deals with the problem of digital demodulation of FM signals transmitted over Rayleigh and Rician fading channels. The Rayleigh and Rician fading channels are represented by two quadrature multiplicative nonzero mean white Gaussian processes in addition to an additive zero-mean white Gaussian noise. Quasi-optimum digital baseband demodulation algorithms using various nonlinear estimation techniques are derived. The digital demodulator structures are then simulated on a digital computer for an FM system with first order message spectrum for various values of the parameters for Rayleigh and Rician channels.

  5. Performance analysis of digital FM demodulators for fading channels in the threshold region

    Science.gov (United States)

    Dharamsi, M. T.; Gupta, S. C.

    1976-01-01

    The quasi-optimum digital FM demodulators for fading channels reported earlier (1975) reflected the system performance accurately under high signal to noise ratio conditions. In this paper, the prediction of the system performance for low SNR values is considered. A new set of error variance algorithms is developed from the filter algorithm assuming a Gaussian distribution for the state estimation errors and taking the effect of high frequency terms into consideration. Simulation analysis for an FM system with Rician fading channel shows that these algorithms predict the system performance accurately in the threshold region.

  6. Study on the cold working process for FM steel cladding tubes

    Science.gov (United States)

    Kim, Tae Kyu; Kim, Sung Ho

    2011-04-01

    A cold working process for FM steel cladding tubes of the sodium-cooled fast reactor was studied. Hot-rolled 9Cr-2W steel plates were heat-treated to dissolve the M 23C 6 and V-rich MX precipitates into the matrix, followed by several cold rollings and intermediate/final heat treatments with the purpose of nucleating the dissolved precipitates on the dislocations formed through the cold rolling. As a result, it was possible to obtain the FM steels with very fine and uniform precipitates which were more promising for superior tensile properties.

  7. In search for the added value of FM: what we know and what we need to learn

    DEFF Research Database (Denmark)

    Jensen, Per Anker; van der Voordt, Theo; Coenen, Christian;

    2012-01-01

    and business-to-business marketing. Findings – Good relationship management and building on trust is shown to be equally important as delivering the agreed services. Originality/value – Usually the concept of added value is discussed from a monodisciplinary point-of-view. The different backgrounds...... of the authors add value to an increased understanding of the added value of FM by comparing and testing different ways of conceptualising this issue. This is of great importance to FM research and evidence-based FM as a sound basis for the long-term recognition of FM....

  8. Scan patterns and accuracy of a Radar Wind Sensor (RAWS)

    Science.gov (United States)

    Song, Shuxian; Beh, Beng; Moore, Richard K.

    1995-01-01

    The Radar Wind Sensor (RAWS) was proposed as a complement to laser wind sensors, allowing coverage in cloudy regions excluded from laser coverage. Previous University of Kansas studies showed the feasibility of the wind measurement at various levels in the atmosphere and indicated that RAWS can also measure rain rates and ocean-surface winds. Here we discuss measurement of the wind vector in terms of the scan patterns for a conically scanned antenna. By using many measurements from cells about 66 km square and 132 km square, a least-squares algorithm gives results that are reasonable for insertion into global atmospheric models. For RAWS to be used successfully as a complement to a laser wind sensor, the design of the two sensors should be integrated and radial velocity measurements in a given atmospheric cell should be combined to get the most accurate results.

  9. A Numerical Method to Generate High Temporal Resolution Precipitation Time Series by Combining Weather Radar Measurements with a Nowcast Model

    DEFF Research Database (Denmark)

    Nielsen, Jesper Ellerbæk; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

    2014-01-01

    The topic of this paper is temporal interpolation of precipitation observed by weather radars. Precipitation measurements with high spatial and temporal resolution are, in general, desired for urban drainage applications. An advection-based interpolation method is developed which uses methods...... for vector field estimation already known from short-term weather radar nowcasting. However, instead of forecasting the weather radar rainfall, the proposed interpolation method exploits the advection of the rainfall in the interpolation. The interpolated rainfall fields are validated by measurements...... at ground level from laser disdrometers. The proposed interpolation method performs better when compared to traditional interpolation of weather radar rainfall where the radar observation is considered constant in time between measurements. It is demonstrated that the advection-based interpolation method...

  10. HPRF pulse Doppler stepped frequency radar

    Institute of Scientific and Technical Information of China (English)

    LONG Teng; REN LiXiang

    2009-01-01

    Stepped frequency radar Is a well known scheme to generate high range resolution profile (HRRP) of targets. Through appropriate radar parameter design, the radar enables both unambiguous velocity measurement and high resolution ranging within a single dwell in a high pulse repetition frequency (HPRF) mode. This paper analyzes in detail the design principle of the HPRF stepped frequency radar system, the solution to its ambiguity issue, as well as its signal processing method. Both theoretical analysis and simulation results demonstrate that the proposed radar scheme can work independently to solve the problem of motion compensation, and is therefore highly applicable to many new types of radar.

  11. Adaptive filters applied on radar signals

    OpenAIRE

    2013-01-01

    This master thesis has been performed at SAAB AB in Järfälla, Sweden.A radar warning receiver must alert the user when someone highlights it with radarsignals. Radar signals used today varies and has a wide frequency band. In order todetect all possible radar signals the radar warning receiver must have a widebandwidth. This results in that the noise power will be high in the radar warningreceiver and weak radar signals will be hard to detect or even undetected.The aim of the thesis work was ...

  12. Co-modulation of WDM-FDM WiMAX-FM and IEEE802.11ac signals by DFB-LD and MZM

    Science.gov (United States)

    Teruya, Miku; Chinen, Koyu

    2017-07-01

    We have investigated how wavelength spacing and frequency spacing in WDM (Wavelength Division Multiplexing) and FDM (Frequency Division Multiplexing) using direct modulation lasers (DML) and external modulators of Mach-Zehnder Modulator (MZM) affect optical and electrical interferences. Two signals of 4.8GHz-64QAM-5MHzBW WiMAX and 4.7GHz-32MHzBW FM were directly modulated with uncooled 1550nm DFB-LDs, and 5GHz-256QAM-80MHzBW IEEE802.11ac signal was modulated on the combined optical signals of WiMAX and FM at an MZM. Change in RCE of the WiMAX signal and EVM of the IEEE 802.11ac signal were measured when the wavelength spacing between two DFB-LDs was varied. When the wavelength spacing was larger than 0.05 nm and the ratio of peak to bottom of optical power was larger than 30 dB, the RCE of WiMAX signal was decreased to lower than -20dB. The WDM using directly modulated DFB-LDs and MZM was realized, when the wavelength spacing was larger than 0.1 nm and the peak to bottom ratio of optical power was larger than 60 dB, since the EVM of IEEE802.11ac signal was decreased to around -30dB. The FDM with the same configuration as that of the WDM was realized, when the frequency spacing was larger than a half of the sum of the BWs of WiMAX and FM signals, as the RCE of WiMAX signal decreased to lower than -35 dB and the EVM of IEEE802.11ac signal decreased to around -30dB.

  13. Radar sounding of Mars from the orbit of the Mars-Express automatic interplanetary station

    Science.gov (United States)

    Smirnov, V. M.; Chernaya, L. F.; Yushkova, O. V.; Rykov, K. N.

    2006-07-01

    On the base of the laser altimetry results obtained using the orbital altimeter MOLA (the MGS mission) and the data of radio occultation experiments of transionospheric sounding of the Mars ionosphere, a method for interpretation of the planet radar sounding data is developed. The proposed method includes a program package for numerical simulation of the process of radiowave propagation through the media under study.

  14. Coded continuous wave meteor radar

    Directory of Open Access Journals (Sweden)

    J. Vierinen

    2015-07-01

    Full Text Available The concept of coded continuous wave meteor radar is introduced. The radar uses a continuously transmitted pseudo-random waveform, which has several advantages: coding avoids range aliased echoes, which are often seen with commonly used pulsed specular meteor radars (SMRs; continuous transmissions maximize pulse compression gain, allowing operation with significantly lower peak transmit power; the temporal resolution can be changed after performing a measurement, as it does not depend on pulse spacing; and the low signal to noise ratio allows multiple geographically separated transmitters to be used in the same frequency band without significantly interfering with each other. The latter allows the same receiver antennas to be used to receive multiple transmitters. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large scale multi-static network of meteor radar transmitters and receivers. This would, for example, provide higher spatio-temporal resolution for mesospheric wind field measurements.

  15. Coded continuous wave meteor radar

    Science.gov (United States)

    Vierinen, J.; Chau, J. L.; Pfeffer, N.; Clahsen, M.; Stober, G.

    2015-07-01

    The concept of coded continuous wave meteor radar is introduced. The radar uses a continuously transmitted pseudo-random waveform, which has several advantages: coding avoids range aliased echoes, which are often seen with commonly used pulsed specular meteor radars (SMRs); continuous transmissions maximize pulse compression gain, allowing operation with significantly lower peak transmit power; the temporal resolution can be changed after performing a measurement, as it does not depend on pulse spacing; and the low signal to noise ratio allows multiple geographically separated transmitters to be used in the same frequency band without significantly interfering with each other. The latter allows the same receiver antennas to be used to receive multiple transmitters. The principles of the signal processing are discussed, in addition to discussion of several practical ways to increase computation speed, and how to optimally detect meteor echoes. Measurements from a campaign performed with a coded continuous wave SMR are shown and compared with two standard pulsed SMR measurements. The type of meteor radar described in this paper would be suited for use in a large scale multi-static network of meteor radar transmitters and receivers. This would, for example, provide higher spatio-temporal resolution for mesospheric wind field measurements.

  16. FM dye photo-oxidation as a tool for monitoring membrane recycling in inner hair cells.

    Directory of Open Access Journals (Sweden)

    Dirk Kamin

    Full Text Available Styryl (FM dyes have been used for more than two decades to investigate exo- and endocytosis in conventional synapses. However, they are difficult to use in the inner hair cells of the auditory pathway (IHCs, as FM dyes appear to penetrate through mechanotransducer channels into the cytosol of IHCs, masking endocytotic uptake. To solve this problem we applied to IHCs the FM dye photo-oxidation technique, which renders the dyes into electron microscopy markers. Photo-oxidation allowed the unambiguous identification of labeled organelles, despite the presence of FM dye in the cytosol. This enabled us to describe the morphologies of several organelles that take up membrane in IHCs, both at rest and during stimulation. At rest, endosome-like organelles were detected in the region of the cuticular plate. Larger tubulo-cisternal organelles dominated the top and nuclear regions. Finally, the basal region, where the IHC active zones are located, contained few labeled organelles. Stimulation increased significantly membrane trafficking in the basal region, inducing the appearance of labeled vesicles and cistern-like organelles. The latter were replaced by small, synaptic-like vesicles during recovery after stimulation. In contrast, no changes in membrane trafficking were induced by stimulation in the cuticular plate region or in the top and nuclear regions. We conclude that synaptic vesicle recycling takes place mostly in the basal region of the IHCs. Other organelles participate in abundant constitutive membrane trafficking throughout the rest of the IHC volume.

  17. Microinjecting FM4-64 validates it as a marker of the endocytic pathway in plants.

    NARCIS (Netherlands)

    Gisbergen, PA van; Esseling-Ozdoba, A.; Vos, J.W.

    2008-01-01

    The amphiphilic dye FM4-64 is used to investigate endocytosis and vesicle trafficking in living eukaryotic cells. The standing hypothesis is that it is inserted into the outer leaflet of the plasma membrane and, from there, is passed on to intracellular membrane compartments by endocytosis. We teste

  18. Microinjecting FM4-64 validates it as a marker of the endocytic pathway in plants

    NARCIS (Netherlands)

    Gisbergen, van P.A.C.; Esseling-Ozdoba, A.; Vos, J.W.

    2008-01-01

    The amphiphilic dye FM4-64 is used to investigate endocytosis and vesicle trafficking in living eukaryotic cells. The standing hypothesis is that it is inserted into the outer leaflet of the plasma membrane and, from there, is passed on to intracellular membrane compartments by endocytosis. We teste

  19. Characteristic polynomial assignment in F-M model Ⅱ of 2-D systems

    Institute of Scientific and Technical Information of China (English)

    唐万生; 亢京力

    2004-01-01

    The problems of characteristic polynomial assignment in Fornasini-Marchesini (F-M) model Ⅱ of 2-D systems are investigated. The corresponding closed-loop systems described by F-M model Ⅱ are obtained via the state feedback.Using the algebraic geometry method, the characteristic polynomial assignment in the closed-loop systems is discussed. In terms of the theory of algebraic geometry, the problem of characteristic polynomial assignment is transferred to the one whether a rational mapping is onto. Sufficient conditions for almost arbitrary assignment coefficients of characteristic polynomial in F-M model Ⅱ of 2-D systems via state feedback are derived, and they are available for multi-input cases. It also has been shown that this method can be applied to assign the characteristic polynomial with output feedback. The sufficient conditions for almost arbitrary assignment coefficients of characteristic polynomial of multi-input 2-D systems described by F-M model Ⅱ with output feedback are established.

  20. 76 FR 65192 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2011-10-20

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: Eastern Sierra Broadcasting, Station KCWK, Facility ID 160324, BMP..., BNPH-20110929AGK, from Rotan, TX, to Roscoe, TX; Everglades City Broadcasting Company, Inc.,...

  1. 76 FR 7848 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2011-02-11

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License Correction In notice document 2011-2764 appearing on pages 6788-6789 in the issue of Tuesday, February 8, 2011,...

  2. 77 FR 57086 - Radio Broadcasting Services; AM or FM Proposals To Change The Community of License.

    Science.gov (United States)

    2012-09-17

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change The Community of License. AGENCY..., Facility ID 50554, BMP-20120725AHO, From TILLAMOOK, OR, To NETARTS, OR; BIRACH BROADCASTING CORPORATION... BROADCASTING CORPORATION, Station KPAD, Facility ID 166006, ] BMPH-20111230ABO, From RAWLINS, WY, To...

  3. 75 FR 66098 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2010-10-27

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: GRACE PUBLIC RADIO, Station KFKB, Facility ID 174471, BMPED-20100803AAM...-20101012ACO, From THOMSON, GA, To NORWOOD, GA; NORTH AMERICAN BROADCASTING COMPANY, INC., Station...

  4. 78 FR 13670 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2013-02-28

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal..., From UNION GROVE, AL, To TRIANA, AL; REED BROADCASTING, LLC, Station WRAB, Facility ID 2552, BP-20130207ABK, From ARAB, AL, To UNION GROVE, AL; SOUTHERN STONE BROADCASTING, INC., Station WMGZ,...

  5. 78 FR 23565 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License.

    Science.gov (United States)

    2013-04-19

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License. AGENCY... BROADCASTING, INC., Station KAKS, Facility ID 69858, BPH- 20130318AGJ, From HUNTSVILLE, AR, To GOSHEN, AR; CARROLL COUNTY BROADCASTING, INC., Station KTHS, Facility ID 35668, BP-20130318AGK, From BERRYVILLE,...

  6. 76 FR 55388 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License.

    Science.gov (United States)

    2011-09-07

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License. AGENCY... proposals to change the community of license: CBS Radio East Inc., Station WLZL, Facility ID 72177, BPH-20110812ACL, from Annapolis, MD, to Bowie, MD; Indiana Community Radio Corporation, Station WYER, Facility...

  7. 78 FR 69086 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2013-11-18

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: CBS RADIO ANNAPOLIS LLC, Station WLZL, Facility ID 20983, BMPH-20131022ALD..., BPH-20130924AJT, From BATH, NY, To AVOCA, NY; PRITCHARD BROADCASTING CORPORATION, Station...

  8. 75 FR 74732 - Radio Broadcasting Services; AM or FM Proposals To Change The Community of License

    Science.gov (United States)

    2010-12-01

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change The Community of License AGENCY: Federal..., Facility ID 46969, BPH-20091230AAY, from Titusville, FL, to Deltona, FL; Hawaii Public Radio, Inc., Station KIPM, Facility ID 172438, BMPED-20101019ACS, from Hana, HI, to Waikapu, HI; Huron Broadcasting,...

  9. 78 FR 41062 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2013-07-09

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal...-20130509ABB, From SMITHS GROVE, KY, To HISEVILLE, KY; HOG RADIO, INC., Station KCYT, Facility ID 51098, BPH- 20130603AES, From OZARK, AR, To FAYETTEVILLE, AR; JOY BROADCASTING, INC., Station WXGN, Facility ID...

  10. 77 FR 62512 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License.

    Science.gov (United States)

    2012-10-15

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License. AGENCY... BROADCASTING ASSOCIATION, Station KLXM, Facility ID 184961, BMPED-20120823AAP, From WEATHERFORD, OK, To ARAPAHO, OK; COMMUNITY RADIO PROJECT, Station KZET, Facility ID 173810, BPED-20120914AEF, From CORTEZ, CO,...

  11. 76 FR 72705 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2011-11-25

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: DOUGLAS BROADCASTING, INC., Station KLNQ, Facility ID161152, BMP-20111107ALX... 90498, BPED-20111103AGS, From LOWELL, IN, To WANATAH, IN; RADIO LICENSE HOLDING CBC, LLC, Station...

  12. 76 FR 50732 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2011-08-16

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal... the community of license: ALELUYA BROADCASTING NETWORK, Station NEW, Facility ID 123270, BMPED..., Facility ID 170991, BPH-20110620AGF, From HAMILTON, TX, To HICO, TX; NORMIN BROADCASTING CO., Station...

  13. 78 FR 9915 - Radio Broadcasting Services; AM or FM Proposals To Change the Community of License

    Science.gov (United States)

    2013-02-12

    ... COMMISSION Radio Broadcasting Services; AM or FM Proposals To Change the Community of License AGENCY: Federal..., From GOSHEN, AL, To BRANTLEY, AL; AZALEA RADIO CORPORATION, Station NEW, Facility ID 183371, BMPH- 20121206ACO, From ROUNDUP, MT, To LEWISTOWN HEIGHTS, MT; COLONIAL RADIO GROUP, INC. Station WBYB, Facility...

  14. FM dye photo-oxidation as a tool for monitoring membrane recycling in inner hair cells.

    Science.gov (United States)

    Kamin, Dirk; Revelo, Natalia H; Rizzoli, Silvio O

    2014-01-01

    Styryl (FM) dyes have been used for more than two decades to investigate exo- and endocytosis in conventional synapses. However, they are difficult to use in the inner hair cells of the auditory pathway (IHCs), as FM dyes appear to penetrate through mechanotransducer channels into the cytosol of IHCs, masking endocytotic uptake. To solve this problem we applied to IHCs the FM dye photo-oxidation technique, which renders the dyes into electron microscopy markers. Photo-oxidation allowed the unambiguous identification of labeled organelles, despite the presence of FM dye in the cytosol. This enabled us to describe the morphologies of several organelles that take up membrane in IHCs, both at rest and during stimulation. At rest, endosome-like organelles were detected in the region of the cuticular plate. Larger tubulo-cisternal organelles dominated the top and nuclear regions. Finally, the basal region, where the IHC active zones are located, contained few labeled organelles. Stimulation increased significantly membrane trafficking in the basal region, inducing the appearance of labeled vesicles and cistern-like organelles. The latter were replaced by small, synaptic-like vesicles during recovery after stimulation. In contrast, no changes in membrane trafficking were induced by stimulation in the cuticular plate region or in the top and nuclear regions. We conclude that synaptic vesicle recycling takes place mostly in the basal region of the IHCs. Other organelles participate in abundant constitutive membrane trafficking throughout the rest of the IHC volume.

  15. 78 FR 59903 - Emission Mask Requirements for Digital Technologies on 800 MHz NPSPAC Channels; Analog FM...

    Science.gov (United States)

    2013-09-30

    ... COMMISSION 47 CFR Part 90 Emission Mask Requirements for Digital Technologies on 800 MHz NPSPAC Channels; Analog FM Capability on Mutual Aid and Interoperability Channels AGENCY: Federal Communications... Petition for Rulemaking filed by Harris Corporation (Harris). The NPRM proposes to require digital...

  16. Microinjecting FM4-64 validates it as a marker of the endocytic pathway in plants.

    NARCIS (Netherlands)

    Gisbergen, PA van; Esseling-Ozdoba, A.; Vos, J.W.

    2008-01-01

    The amphiphilic dye FM4-64 is used to investigate endocytosis and vesicle trafficking in living eukaryotic cells. The standing hypothesis is that it is inserted into the outer leaflet of the plasma membrane and, from there, is passed on to intracellular membrane compartments by endocytosis. We

  17. Microinjecting FM4-64 validates it as a marker of the endocytic pathway in plants

    NARCIS (Netherlands)

    Gisbergen, van P.A.C.; Esseling-Ozdoba, A.; Vos, J.W.

    2008-01-01

    The amphiphilic dye FM4-64 is used to investigate endocytosis and vesicle trafficking in living eukaryotic cells. The standing hypothesis is that it is inserted into the outer leaflet of the plasma membrane and, from there, is passed on to intracellular membrane compartments by endocytosis. We

  18. Evaluating the capabilities and uncertainties of droplet measurements for the fog droplet spectrometer (FM-100

    Directory of Open Access Journals (Sweden)

    J. K. Spiegel

    2012-05-01

    Full Text Available Droplet size spectra measurements are crucial to obtain a quantitative microphysical description of clouds and fog. However, cloud droplet size measurements are subject to various uncertainties. This work focuses on the evaluation of two key measurement uncertainties arising during cloud droplet size measurements with a conventional droplet size spectrometer (FM-100: first, we addressed the precision with which droplets can be sized with the FM-100 on the basis of Mie theory. We deduced error assumptions and proposed how to correct measured size distributions for these errors by redistributing the measured droplet size distribution using a stochastic approach. Second, based on a literature study, we derived corrections for particle losses during sampling with the FM-100. We applied both corrections to cloud droplet size spectra measured at the high alpine site Jungfraujoch for a temperature range from 0 °C to 11 °C. We show that Mie scattering led to spikes in the droplet size distributions using the default sizing procedure, while the stochastic approach reproduced the ambient size distribution adequately. A detailed analysis of the FM-100 sampling efficiency revealed that particle losses were typically below 10% for droplet diameters up to 10 μm. For larger droplets, particle losses can increase up to 90% for the largest droplets of 50 μm at ambient windspeeds below 4.4 m s−1 and even to >90% for larger angles between the instrument orientation and the wind vector (sampling angle at higher wind speeds. Comparisons of the FM-100 to other reference instruments revealed that the total liquid water content (LWC measured by the FM-100 was more sensitive to particle losses than to re-sizing based on Mie scattering, while the total number concentration was only marginally influenced by particle losses. As a consequence, for further LWC measurements with the FM-100 we strongly recommend to consider (1 the error arising due to Mie

  19. Evaluating the capabilities and uncertainties of droplet measurements for the fog droplet spectrometer (FM-100

    Directory of Open Access Journals (Sweden)

    J. K. Spiegel

    2012-09-01

    Full Text Available Droplet size spectra measurements are crucial to obtain a quantitative microphysical description of clouds and fog. However, cloud droplet size measurements are subject to various uncertainties. This work focuses on the error analysis of two key measurement uncertainties arising during cloud droplet size measurements with a conventional droplet size spectrometer (FM-100: first, we addressed the precision with which droplets can be sized with the FM-100 on the basis of the Mie theory. We deduced error assumptions and proposed a new method on how to correct measured size distributions for these errors by redistributing the measured droplet size distribution using a stochastic approach. Second, based on a literature study, we summarized corrections for particle losses during sampling with the FM-100. We applied both corrections to cloud droplet size spectra measured at the high alpine site Jungfraujoch for a temperature range from 0 °C to 11 °C. We showed that Mie scattering led to spikes in the droplet size distributions using the default sizing procedure, while the new stochastic approach reproduced the ambient size distribution adequately. A detailed analysis of the FM-100 sampling efficiency revealed that particle losses were typically below 10% for droplet diameters up to 10 μm. For larger droplets, particle losses can increase up to 90% for the largest droplets of 50 μm at ambient wind speeds below 4.4 m s−1 and even to >90% for larger angles between the instrument orientation and the wind vector (sampling angle at higher wind speeds. Comparisons of the FM-100 to other reference instruments revealed that the total liquid water content (LWC measured by the FM-100 was more sensitive to particle losses than to re-sizing based on Mie scattering, while the total number concentration was only marginally influenced by particle losses. Consequently, for further LWC measurements with the FM-100 we strongly recommend to consider (1 the

  20. A theoretical and experimental analysis of modulated laser fields and power spectra

    DEFF Research Database (Denmark)

    Olesen, Henning; Jacobsen, G.

    1982-01-01

    A general theoretical description of modulated laser fields and power spectra for a current modulated single-mode laser is derived, taking into account both the intensity and frequency modulation (IM and FM) of the emitted light. The theory relies on an explicit knowledge of the modulus as well...