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Sample records for monolithic power amplifier

  1. Analysis of monolithic integrated master oscillator power amplifiers

    Science.gov (United States)

    Mehuys, David; Welch, David F.; Waarts, Robert G.; Parke, Ross; Hardy, Amos; Streifer, William

    1991-07-01

    An analysis of a novel, monolithic integrated master oscillator power amplifier (M-MOPA) is presented. The M-MOPA consists of a DBR master oscillator which injects power into a linear chain of amplifiers and detuned second-order grating output couplers. The analysis self-consistently includes amplified spontaneous emission buildup and residual reflections throughout the amplifier stages. It predicts that output powers in excess of 1 W can be expected from a single-lateral-mode waveguide multistage amplifier less than 1 cm in length, injected with less than 15 mW of input power. In addition to the signal gain of more than 25 dB, the signal-to-noise ratio at 1-W output exceeds 15 dB. Because of the small reflections associated with the grating output couplers, and gain saturation by the injected signal, the amplifier self-oscillation threshold is suppressed to current densities above 15 kA/sq cm.

  2. GaN Monolithic Power Amplifiers for Microwave Backhaul Applications

    Directory of Open Access Journals (Sweden)

    Roberto Quaglia

    2016-06-01

    Full Text Available Gallium nitride integrated technology is very promising not only for wireless applications at mobile frequencies (below 6 GHz but also for network backhaul radiolink deployment, now under deep revision for the incoming 5G generation of mobile communications. This contribution presents three linear power amplifiers realized on 0.25 μ m Gallium Nitride on Silicon Carbide monolithic integrated circuits for microwave backhaul applications: two combined power amplifiers working in the backhaul band around 7 GHz, and a more challenging third one working in the higher 15 GHz band. Architectures and main design steps are described, highlighting the pros and cons of Gallium Nitride with respect to the reference technology which, for these applications, is represented by gallium arsenide.

  3. Phased array of high-power, coherent, monolithic flared amplifier master oscillator power amplifiers

    Science.gov (United States)

    Osinski, J. S.; Mehuys, D.; Welch, D. F.; Waarts, R. G.; Major, J. S., Jr.; Dzurko, K. M.; Lang, R. J.

    1995-01-01

    A monolithically integrated array of InGaAs/AlGaAs flared amplifiers driven by a single DBR laser through a power splitter network and individually addressed phase modulators is described. Phase adjustment of ≳2π per element by free-carrier effects is verified by monitoring the interference pattern of all four emitters, and typically requires <15 mA of current to obtain a 2π phase shift. Phase matching is achieved among all four diffraction-limited emitters at a pulsed output power of ≳5 W, and, combined with the proper external lensing, could therefore result in an ultranarrow, single-lobed far-field pattern whose width is determined by the extended aperture of the array.

  4. Monolithic Microwave Integrated Circuits (MMIC) Broadband Power Amplifiers (Part 2)

    Science.gov (United States)

    2013-07-01

    2 Figure 2. A 2-GHz load-pull simulation of output power (Pcomp-6 x 65 µm PHEMT). ..............2 Figure 3. A 2-GHz load-pull simulation of PAE (6...5. MMIC 1–5 GHz output power and PAE performance simulation (1, 2, 3, and 4 GHz...load-pull simulation of PAE (6 x 50 µm PHEMT). .......................................7 Figure 9. MMIC 10–19 GHz broadband power amplifier linear

  5. High-power coherent phased array of monolithic flared amplifier-master oscillator power amplifiers (MFA-MOPAs)

    Science.gov (United States)

    Osinski, Jules S.; Mehuys, David G.; Welch, David F.; Dzurko, Kenneth M.; Lang, Robert J.

    1995-04-01

    A monolithically integrated array of InGaAs/AlGaAs flared amplifiers driven by a single DBR laser through a power splitter network and individually addressed phase modulators is described. Phase adjustment of > 2(pi) per element by free-carrier effects is verified by monitoring the interference pattern of 4 emitters, and typically requires 5 W, and, combined with the proper external lensing, could therefore result in an ultra-narrow, single-lobed far-field pattern whose width is determined by the extended aperture of the array. This architecture is capable of providing single-mode, diffraction-limited performance from each emitter and is scalable to unprecedented power levels. Over 20 W of pulsed, spectrally coherent emission is generated at 955 nm from a 4-element array, and 39 W is obtained from an 8-element array.

  6. Monolithic Microwave Integrated Circuits (MMIC) Broadband Power Amplifiers

    Science.gov (United States)

    2012-12-01

    Pcomp-6x50 µm PHEMT). .............4 Figure 4. An 8-GHz load-pull simulation of PAE (6x50 µm PHEMT). ........................................4...layout. ..........................................................................9 Figure 12. MMIC 5–11 GHz output power and PAE performance...6x50 µm PHEMT). ...........11 Figure 16. A 4-GHz load-pull simulation of PAE (6x50 µm PHEMT). ......................................12 Figure 17

  7. A Ku-band high power density AlGaN/GaN HEMT monolithic power amplifier

    Institute of Scientific and Technical Information of China (English)

    Ge Qin; Chen Xiaojuan; Luo Weijun; Yuan Tingting; Pang Lei; Liu Xinyu

    2011-01-01

    A high power density monolithic power amplifier operated at Ku band is presented utilizing a 0.3 μm AlGaN/GaN HEMT production process on a 2-inch diameter semi-insulating (SI) 4H-SiC substrate by MOCVD.Over the 12-14 GHz frequency range,the single chip amplifier demonstrates a maximum power of 38 dBm (6.3 W),a peak power added efficiency (PAE) of 24.2% and linear gain of 6.4 to 7.5 dB under a 10% duty pulse conditionwhen operated at Vds =25 V and Vgs =-4 V.At these power levels,the amplifier exhibits a power density in excess of 5 W/mm.

  8. Evolution of Monolithic Technology for Wireless Communications: GaN MMIC Power Amplifiers For Microwave Radios

    Directory of Open Access Journals (Sweden)

    Vittorio Camarchia

    2014-09-01

    Full Text Available This paper presents the progress of monolithic technology for microwaveapplication, focusing on gallium nitride technology advances in the realization of integratedpower amplifiers. Three design examples, developed for microwave backhaul radios, areshown. The first design is a 7 GHz Doherty developed with a research foundry, while thesecond and the third are a 7 GHz Doherty and a 7–15 GHz dual-band combined poweramplifiers, both based on a commercial foundry process. The employed architectures, themain design steps and the pros and cons of using gallium nitride technology are highlighted.The measured performance demonstrates the potentialities of the employed technology, andthe progress in the accuracy, reliability and performance of the process.

  9. 单片集成微波/射频功率放大器技术进展%Progress in Monolithic Integrated Microwave/RF Power Amplifier

    Institute of Scientific and Technical Information of China (English)

    李强; 严利人; 周卫; 张伟

    2011-01-01

    As wireless communication market increases, monolithic integrated microwave/RF power amplifier (MMIC PA) plays a more and more important role in 3G and/or 4G systems. Traditional circuits used in mono-stage amplifiers are reviewed, together with their pros and cons. Architectures, such as the Doherty circuitry, EER (Envelope Elimination and Restoration) technology, LINC, etc. , are also discussed. Generally, these technologies may be used to improve linearity and efficiency of microwave power amplifier. Currently, some system-level linearization techniques have also been utilized. The overview may serve as a useful groundwork for those who are designing MMIC Pas.%回顾了一些用于微波单级功率放大器的传统技术方案,讨论了各自的优缺点.从电路模块的角度,总结了若干兼顾功放线性度和效率指标的典型电路拓扑形式,包括Doherty电路、包络消除与恢复(EER)技术、LINC技术等,并总结了当前主要采用的基于电路系统层面的微波射频功放线性化方案.在此基础上,列举评点了文献中一些典型功放的电路特点和性能指标,可为设计和制造人员提供有益参考.

  10. 51.5 W monolithic single frequency 1.97 μm Tm-doped fiber amplifier

    Institute of Scientific and Technical Information of China (English)

    Xiong; Wang; Pu; Zhou; Xiaolin; Wang; Hu; Xiao; Lei; Si

    2013-01-01

    We demonstrate a monolithic single frequency Tm-doped fiber amplifier with output power of 51.5 W. A single frequency fiber laser at 1.97 μm is amplified by a cascaded master oscillator power amplifier(MOPA) system with all-fiber configuration. The optical-to-optical conversion efficiency of the main fiber amplifier is 45%. No amplified spontaneous emission(ASE) or stimulated Brillouin scattering(SBS) effect is observed in the fiber amplifier. The output power could be further scaled by launching more pump power.

  11. RF Power Amplifier Analysis

    Directory of Open Access Journals (Sweden)

    M. Lokay

    1993-04-01

    Full Text Available The special program is presented for the demonstration of RF power transistor amplifiers for the purposes of the high-school education in courses of radio transmitters. The program is written in Turbo Pascal 6. 0 and enables to study the waveforms in selected points of the amplifier and to draw the trajectories of the working point in a plot of output transistor characteristics.

  12. Design of High Power Density Amplifiers: Application to Ka Band

    Science.gov (United States)

    Passi, Davide; Leggieri, Alberto; Di Paolo, Franco; Bartocci, Marco; Tafuto, Antonio

    2017-06-01

    Recent developments in the design of high-power-high-frequency amplifiers are assessed in this paper by the analysis and measurements of a high power density amplifier operating in the Ka Band. Design procedure is presented and a technical investigation is reported. The proposed device has shown over 23% of useful frequency bandwidth. It is an ensemble of 16 monolithic solid state power amplifiers that employees mixed technologies as spatial and planar combiners. Test performed have given maximum delivered power of 47.2 dBm.

  13. Two stage dual gate MESFET monolithic gain control amplifier for Ka-band

    Science.gov (United States)

    Sokolov, V.; Geddes, J.; Contolatis, A.

    A monolithic two stage gain control amplifier has been developed using submicron gate length dual gate MESFETs fabricated on ion implanted material. The amplifier has a gain of 12 dB at 30 GHz with a gain control range of over 30 dB. This ion implanted monolithic IC is readily integrable with other phased array receiver functions such as low noise amplifiers and phase shifters.

  14. Fabrication of Tunable Sampled Grating DBR Laser Integrated Monolithically with Optical Semiconductor Amplifier Using Planar Buried Heterostructure

    Science.gov (United States)

    Oh, Su Hwan; Lee, Ji-Myon; Kim, Soo; Ko, Hyunsung; Lee, Chul-Wook; Park, Sahnggi; Park, Moon-Ho

    2004-10-01

    We have demonstrated a high-power widely tunable sampled grating (SG) DBR laser integrated monolithically with optical semiconductor amplifier (SOA), using planar buried heterostructure (PBH). The measured threshold current was 5 mA on average with 60 chips randomly selected which is lowest among the typical average values. Fiber-coupled output power was 12.4 dBm and the output power variation was ˜1 dB for the whole tuning range.

  15. Monolithic fuel cell based power source for burst power generation

    Science.gov (United States)

    Fee, D. C.; Blackburn, P. E.; Busch, D. E.; Dees, D. W.; Dusek, J.; Easler, T. E.; Ellingson, W. A.; Flandermeyer, B. K.; Fousek, R. J.; Heiberger, J. J.

    A unique fuel cell coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The monolithic fuel cell looks attractive for space applications and represents a quantum jump in fuel cell technology. Such a breakthrough in design is the enabling technology for lightweight, low volume power sources for space based pulse power systems. The monolith is unique among fuel cells in being an all solid state device. The capability for miniaturization, inherent in solid state devices, gives the low volume required for space missions. In addition, the solid oxide fuel cell technology employed in the monolith has high temperature reject heat and can be operated in either closed or open cycles. Both these features are attractive for integration into a burst power system.

  16. Development of High Power Amplifiers for Space and Ground-based Applications

    DEFF Research Database (Denmark)

    Hernández, Carlos Cilla

    and the Monolithic Microwave Integrated Circuits. The research work presented here focuses on practical realization and demonstration of these two types of amplifiers. The design and experimental performance assessment of 50W Solid State C-band High Power Amplifier using European Monolithic Microwave Integrated......-based amplifiers. They are efficient and provide very high power levels operating at low duty cycles. But they have a questionable longterm reliability, large footprints and they are not suitable for modern equipment with a decentralized transmitter, like a phase array system. Solid State Power Amplifier......D dissertation lies in the development of nonlinear design methodologies, manufacturing, and efficient testing of Solid State High Power Amplifier modules, with special focus on GaN state of the art technology. It is possible to identify two types of GaN Solid State High Power Amplifiers: the Hybrids...

  17. High power RF solid state power amplifier system

    Science.gov (United States)

    Sims, III, William Herbert (Inventor); Chavers, Donald Gregory (Inventor); Richeson, James J. (Inventor)

    2011-01-01

    A high power, high frequency, solid state power amplifier system includes a plurality of input multiple port splitters for receiving a high-frequency input and for dividing the input into a plurality of outputs and a plurality of solid state amplifier units. Each amplifier unit includes a plurality of amplifiers, and each amplifier is individually connected to one of the outputs of multiport splitters and produces a corresponding amplified output. A plurality of multiport combiners combine the amplified outputs of the amplifiers of each of the amplifier units to a combined output. Automatic level control protection circuitry protects the amplifiers and maintains a substantial constant amplifier power output.

  18. Linearisation of RF Power Amplifiers

    DEFF Research Database (Denmark)

    Nielsen, Per Asbeck

    2001-01-01

    This thesis deals with linearisation techniques of RF power amplifiers (PA), PA design techniques and integration of the necessary building blocks in a CMOS technology. The opening chapters introduces the theory of transmitter architectures, RF-signal representation and the principles of digital...... modulation. Furthermore different types of power amplifiers, models and measures of non-linearities are presented. A chapter is also devoted to different types of linearisation systems. The work carried out and described in this thesis can be divided into a more theoretical and system oriented treatment...... the polar loop architecture and it’s suitability to modern digital transmitters is discussed. A proposal of an architecture that is suitable for digital transmitters, which means that it has an interface to the digital back-end, defined by low-pass signals in polar form, is presented. Simulation guidelines...

  19. Small and lightweight power amplifiers

    Science.gov (United States)

    Shams, Qamar A.; Barnes, Kevin N.; Fox, Robert L.; Moses, Robert W.; Bryant, Robert G.; Robinson, Paul C.; Shirvani, Mir

    2002-07-01

    The control of u wanted structural vibration is implicit in most of NASA's programs. Currently several approaches to control vibrations in large, lightweight, deployable structures and twin tail aircraft at high angles of attack are being evaluated. The Air Force has been examining a vertical tail buffet load alleviation system that can be integrated onboard an F/A-18 and flown. Previous wind tunnel and full-scale ground tests using distributed actuators have shown that the concept works; however, there is insufficient rom available onboard an F/A-18 to store current state-of- the-art system components such as amplifiers, DC-to-DC converter and a computer for performing vibration suppression. Sensor processing, power electronics, DC-to-DC converters, and control electronics that may be collocated with distributed actuators, are particularly desirable. Such electronic system would obviate the need for complex, centralized, control processing and power distribution components that will eliminate the weight associated with lengthy wiring and cabling networks. Several small and lightweight power amplifiers ranging from 300V pp to 650V pp have been designed using off the shelf components for different applications. In this paper, the design and testing of these amplifiers will be presented under various electrical loads.

  20. Monolithically integrated quantum dot optical modulator with Semiconductor optical amplifier for short-range optical communications

    Science.gov (United States)

    Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya

    2015-04-01

    A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed. Broadband QD optical gain material was used to achieve Gbps-order high-speed optical data transmission, and an optical gain change as high as approximately 6-7 dB was obtained with a low OGM voltage of 2.0 V. Loss of optical power due to insertion of the device was also effectively compensated for by the SOA section. Furthermore, it was confirmed that the QD-OGM/SOA device helped achieve 6.0-Gbps error-free optical data transmission over a 2.0-km-long photonic crystal fiber. We also successfully demonstrated generation of Gbps-order, high-speed, and error-free optical signals in the >5.5-THz broadband optical frequency bandwidth larger than the C-band. These results suggest that the developed monolithically integrated QD-OGM/SOA device will be an advantageous and compact means of increasing the usable optical frequency channels for short-reach communications.

  1. Audio power amplifier design handbook

    CERN Document Server

    Self, Douglas

    2013-01-01

    This book is essential for audio power amplifier designers and engineers for one simple reason...it enables you as a professional to develop reliable, high-performance circuits. The Author Douglas Self covers the major issues of distortion and linearity, power supplies, overload, DC-protection and reactive loading. He also tackles unusual forms of compensation and distortion produced by capacitors and fuses. This completely updated fifth edition includes four NEW chapters including one on The XD Principle, invented by the author, and used by Cambridge Audio. Cro

  2. Monolithic integration of erbium-doped amplifiers with silicon-on-insulator waveguides.

    Science.gov (United States)

    Agazzi, Laura; Bradley, Jonathan D B; Dijkstra, Meindert; Ay, Feridun; Roelkens, Gunther; Baets, Roel; Wörhoff, Kerstin; Pollnau, Markus

    2010-12-20

    Monolithic integration of Al2O3:Er3+ amplifier technology with passive silicon-on-insulator waveguides is demonstrated. A signal enhancement of >7 dB at 1533 nm wavelength is obtained. The straightforward wafer-scale fabrication process, which includes reactive co-sputtering and subsequent reactive ion etching, allows for parallel integration of multiple amplifier and laser sections with silicon or other photonic circuits on a chip.

  3. low pump power photonic crystal fibre amplifiers

    DEFF Research Database (Denmark)

    Hougaard, Kristian G.; Broeng, Jes; Bjarklev, Anders Overgaard

    2003-01-01

    Designs of low pump power optical amplifiers, based on photonic crystal fibres are presented. The potential of these fibre amplifiers is investigated, and it is demonstrated that such amplifiers may deliver gains of more than 15 dB at 1550 nm with less than 1 mW of optical pump power....

  4. Complex coupled distributed feedback laser monolithically integrated with electroabsorption modulator and semiconductor optical amplifier at 1.3-micrometer wavelength

    Science.gov (United States)

    Gerlach, Philipp; Peschke, Martin; Wenger, Thomas; Saravanan, Brem K.; Hanke, Christian; Lorch, Steffen; Michalzik, Rainer

    2006-04-01

    We report on the design and experimental results of monolithically integrated optoelectronic devices containing distributed feedback (DFB) laser, electroabsorption modulator (EAM), and semiconductor optical amplifier (SOA). Common InGaAlAs multiple quantum well (MQW) layers are used in all device sections. The incorporation of local lateral metal gratings in the DFB section enables device fabrication by single-step epitaxial growth. The emission wavelength is λ=1.3 micrometer. More than 2 mW single-mode fiber-coupled output power as well as 10 dB/2 V static extinction ratio have been achieved. Modulation experiments clearly show 10 Gbit/s capability.

  5. A High-Efficiency 4x45W Car Audio Power Amplifier using Load Current Sharing

    NARCIS (Netherlands)

    Mensink, C.H.J.; Mensink, C.; van Tuijl, Adrianus Johannes Maria; Gierkink, Sander L.J.; Mostert, F.; van der Zee, Ronan A.R.

    2010-01-01

    A 4x45W (EIAJ) monolithic car audio power amplifier is presented that achieves a power dissipation decrease of nearly 2x over standard class AB operation by sharing load currents between loudspeakers. Output signals are conditioned using a common-mode control loop to allow switch placement between l

  6. A High-Efficiency 4x45W Car Audio Power Amplifier using Load Current Sharing

    NARCIS (Netherlands)

    Mensink, C.H.J.; Mensink, C.; van Tuijl, Adrianus Johannes Maria; Gierkink, Sander L.J.; Mostert, F.; van der Zee, Ronan A.R.

    2010-01-01

    A 4x45W (EIAJ) monolithic car audio power amplifier is presented that achieves a power dissipation decrease of nearly 2x over standard class AB operation by sharing load currents between loudspeakers. Output signals are conditioned using a common-mode control loop to allow switch placement between

  7. High Average Power Optical FEL Amplifiers

    CERN Document Server

    Ben-Zvi, I; Litvinenko, V

    2005-01-01

    Historically, the first demonstration of the FEL was in an amplifier configuration at Stanford University. There were other notable instances of amplifying a seed laser, such as the LLNL amplifier and the BNL ATF High-Gain Harmonic Generation FEL. However, for the most part FELs are operated as oscillators or self amplified spontaneous emission devices. Yet, in wavelength regimes where a conventional laser seed can be used, the FEL can be used as an amplifier. One promising application is for very high average power generation, for instance a 100 kW average power FEL. The high electron beam power, high brightness and high efficiency that can be achieved with photoinjectors and superconducting energy recovery linacs combine well with the high-gain FEL amplifier to produce unprecedented average power FELs with some advantages. In addition to the general features of the high average power FEL amplifier, we will look at a 100 kW class FEL amplifier is being designed to operate on the 0.5 ampere Energy Recovery Li...

  8. Design procedure for millimeter-wave InP DHBT stacked power amplifiers

    DEFF Research Database (Denmark)

    Squartecchia, Michele; Johansen, Tom Keinicke; Midili, Virginio

    2015-01-01

    The stacked-transistor concept for power amplifiers (PA) has been investigated in this work. Specifically, this architecture has been applied in the design of millimeter-wave monolithic microwave integrated circuits (MMICs) using indium phosphide (InP) double heterojunction bipolar transistors...

  9. An Envelope Hammerstein Model for Power Amplifiers

    Institute of Scientific and Technical Information of China (English)

    Hua-Dong Wang; Song-Bai He; Jing-Fu Bao; Zheng-De Wu

    2007-01-01

    In this paper, an envelope Hammerstein(EH) model is introduced to describe dynamic inputoutput characteristics of RF power amplifiers. In the modeling approach, we use a new truncation method and an established nonlinear time series method to determine model structure. Then, we discuss the process of model parameter extraction in detailed. Finally, a 2 W WCDMA power amplifier is measured to verify the performance of EH model, and good agreement between model output and measurement result shows our model can accurately predict output characteristic of the power amplifier.

  10. High power Ka band TWT amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Golkowski, C.; Ivers, J.D.; Nation, J.A.; Wang, P.; Schachter, L.

    1999-07-01

    Two high power 35 GHz TWT amplifiers driven by a relativistic pencil, 850 kV, 200A electron beam have been assembled and tested. The first had a dielectric slow wave structure and was primarily used to develop diagnostics, and to gain experience in working with high power systems in Ka band. The source of the input power for the amplifier was a magnetron producing a 30 kW, 200ns long pulse of which 10 kW as delivered to the experiment. The 30 cm long dielectric (Teflon) amplifier produced output power levels of about 1 MW with a gain of about 23 dB. These results are consistent with expectations from PIC code simulations for this arrangement. The second amplifier, which is a single stage disk loaded slow wave structure, has been designed. It consists of one hundred uniform cells with two sets of ten tapered calls at the ends to lower the reflection coefficient. The phase advance per cell is {pi}/2. The amplifier passband extends from 28 to 40 GHz. It is designed to increase the output power to about 20 MW. The amplifier is in construction and will be tested in the near future. Details of the design of both systems will be provided and initial results from the new amplifier presented.

  11. High power regenerative laser amplifier

    Science.gov (United States)

    Miller, J.L.; Hackel, L.A.; Dane, C.B.; Zapata, L.E.

    1994-02-08

    A regenerative amplifier design capable of operating at high energy per pulse, for instance, from 20-100 Joules, at moderate repetition rates, for instance from 5-20 Hertz is provided. The laser amplifier comprises a gain medium and source of pump energy coupled with the gain medium; a Pockels cell, which rotates an incident beam in response to application of a control signal; an optical relay system defining a first relay plane near the gain medium and a second relay plane near the rotator; and a plurality of reflectors configured to define an optical path through the gain medium, optical relay and Pockels cell, such that each transit of the optical path includes at least one pass through the gain medium and only one pass through the Pockels cell. An input coupler, and an output coupler are provided, implemented by a single polarizer. A control circuit coupled to the Pockels cell generates the control signal in timed relationship with the input pulse so that the input pulse is captured by the input coupler and proceeds through at least one transit of the optical path, and then the control signal is applied to cause rotation of the pulse to a polarization reflected by the polarizer, after which the captured pulse passes through the gain medium at least once more and is reflected out of the optical path by the polarizer before passing through the rotator again to provide an amplified pulse. 7 figures.

  12. High Efficiency Microwave Power Amplifier (HEMPA) Design

    Science.gov (United States)

    Sims, W. Herbert

    2004-01-01

    This paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  13. Monolithic integration of widely tunable sampled grating DBR laser with tilted semiconductor optical amplifier

    Science.gov (United States)

    Ye, Nan; Liu, Yang; Wang, BaoJun; Zhou, DaiBing; Pang, JiaoQing; Zhao, LingJuan; Wang, Wei

    2011-01-01

    More than 11mW output powers for all wavelengths from the fiber and over 49 nm range tuning in sampled grating distributed Bragg reflector laser with an integrated semiconductor optical amplifier which is enabling access to 110 ITU 50GHz channels is demonstrated. Tilted amplifier and anti-reflection facet coating are used to suppress reflection.

  14. Monolithic integration of widely tunable sampled grating DBR laser with tilted semiconductor optical amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yang; Ye Nan; Wang Baojun; Zhou Daibing; An Xin; Bian Jing; Pan Jiaoqing; Zhao Lingjuan; Wang Wei, E-mail: matsu@semi.ac.c [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2010-07-15

    High output powers and wide range tuning have been achieved in a sampled grating distributed Bragg reflector laser with an integrated semiconductor optical amplifier. Tilted amplifier and anti-reflection facet coating are used to suppress reflection. We have demonstrated sampled grating DBR laser with a tuning range over 38 nm, good wavelength coverage and peak output powers of more than 9 mW for all wavelengths.

  15. Laser Cooled High-Power Fiber Amplifier

    CERN Document Server

    Nemova, Galina

    2009-01-01

    A theoretical model for laser cooled continuous-wave fiber amplifier is presented. The amplification process takes place in the Tm3+-doped core of the fluoride ZBLAN (ZrF4-BaF2-LaF3-AlF3-NaF) glass fiber. The cooling process takes place in the Yb3+:ZBLAN fiber cladding. It is shown that for each value of the pump power and the amplified signal there is a distribution of the concentration of the Tm3+ along the length of the fiber amplifier, which provides its athermal operation. The influence of a small deviation in the value of the amplified signal on the temperature of the fiber with the fixed distribution of the Tm3+ions in the fiber cladding is investigated.

  16. Evaluation of the resistance to progressive collapse of monolithic reinforced concrete frame buildingswith separate amplified floors

    Directory of Open Access Journals (Sweden)

    Domarova Ekaterina Vladimirovna

    2014-02-01

    Full Text Available In the article the authors propose a simplified method of dynamic analysis of the resistance to progressive collapse of a fragment of the building bearing system with amplified floors. This method is based on representing the building bearing system as a dynamic model with a denumerable number of degrees of freedom, in which the resistance of the system is provided mainly by the behavior of the columns. The degrees of freedom number is determined by the number of floors «hanging» to amplified floors. Thecontribution of slabs in the total system resistance is not taken into account. Stress-strain state of the columns is determined by the non-linear resistance diagram, including three stages: elastic, elastic with cracks and plastic stage connected with plastic yield in the steel of the columns. The criterion of sustainability to the progressive collapse is relative strain of steel of the undestroyed columns. A numerical example of the calculation of the building resistance to progressive collapse in case of sudden destruction of one vertical element based on proposed theoretical method is offered. A model with two numbers of degrees was considered. The suggested method allows estimating the strength, deformability and stability of monolithic reinforced concrete frame buildings with separate amplified floors. In the future it is intended to complicate the model by the accounting for the influence of deformation and constructive solution of the slabs on the stiffness characteristics of the model as a system with a finite number of degrees of freedom.

  17. Modeling Power Amplifiers using Memory Polynomials

    NARCIS (Netherlands)

    Kokkeler, Andre B.J.

    2005-01-01

    In this paper we present measured in- and output data of a power amplifier (PA). We compare this data with an AM-AM and AM-PM model. We conclude that a more sophisticated PA model is needed to cope with severe memory effects. We suggest to use memory polynomials and introduce two approaches to

  18. High power, high beam quality regenerative amplifier

    Science.gov (United States)

    Hackel, L.A.; Dane, C.B.

    1993-08-24

    A regenerative laser amplifier system generates high peak power and high energy per pulse output beams enabling generation of X-rays used in X-ray lithography for manufacturing integrated circuits. The laser amplifier includes a ring shaped optical path with a limited number of components including a polarizer, a passive 90 degree phase rotator, a plurality of mirrors, a relay telescope, and a gain medium, the components being placed close to the image plane of the relay telescope to reduce diffraction or phase perturbations in order to limit high peak intensity spiking. In the ring, the beam makes two passes through the gain medium for each transit of the optical path to increase the amplifier gain to loss ratio. A beam input into the ring makes two passes around the ring, is diverted into an SBS phase conjugator and proceeds out of the SBS phase conjugator back through the ring in an equal but opposite direction for two passes, further reducing phase perturbations. A master oscillator inputs the beam through an isolation cell (Faraday or Pockels) which transmits the beam into the ring without polarization rotation. The isolation cell rotates polarization only in beams proceeding out of the ring to direct the beams out of the amplifier. The diffraction limited quality of the input beam is preserved in the amplifier so that a high power output beam having nearly the same diffraction limited quality is produced.

  19. Design Of A Doherty Power Amplifier For GSM Systems

    Directory of Open Access Journals (Sweden)

    Saad Wasmi Osman

    2013-04-01

    Full Text Available This paper presents the design and analysis of Doherty power amplifier. The Doherty amplifier is used in  a base station for mobile system because of its high efficiency. The class AB power amplifier used in the configuration of the main and auxiliary amplifier. The result obtained shows that the Doherty power amplifier can be used on a wide band spectrum, the amplifier works at 900MHz and has very good power added efficiency (PAE and gain. The amplifier can also work at 1800MHz at input power greater than 20dBm. 

  20. High Efficiency Ka-Band Solid State Power Amplifier Waveguide Power Combiner

    Science.gov (United States)

    Wintucky, Edwin G.; Simons, Rainee N.; Chevalier, Christine T.; Freeman, Jon C.

    2010-01-01

    A novel Ka-band high efficiency asymmetric waveguide four-port combiner for coherent combining of two Monolithic Microwave Integrated Circuit (MMIC) Solid State Power Amplifiers (SSPAs) having unequal outputs has been successfully designed, fabricated and characterized over the NASA deep space frequency band from 31.8 to 32.3 GHz. The measured combiner efficiency is greater than 90 percent, the return loss greater than 18 dB and input port isolation greater than 22 dB. The manufactured combiner was designed for an input power ratio of 2:1 but can be custom designed for any arbitrary power ratio. Applications considered are NASA s space communications systems needing 6 to 10 W of radio frequency (RF) power. This Technical Memorandum (TM) is an expanded version of the article recently published in Institute of Engineering and Technology (IET) Electronics Letters.

  1. On Distortion in Digital Microwave Power Amplifiers

    Science.gov (United States)

    Al-Mozani, Dhamia; Wentzel, Andreas; Heinrich, Wolfgang

    2017-01-01

    In this paper, a first study of distortion in digital power amplifiers (PA) is presented. The work is based on a voltage mode class-S PA with a GaN MMIC for the 900 MHz frequency band. The investigation focuses on the quasi-static amplitude-to-amplitude (AM-AM) and amplitude-to-phase (AM-PM) distortions. Different digital modulation schemes are applied and studied versus output power back-off. This includes two pulse-width modulation (PWM) versions as well as band-pass delta-sigma (BPDS) modulation. The results are verified by measurement data.

  2. High Power Amplifier and Power Supply

    Science.gov (United States)

    Duong, Johnny; Stride, Scot; Harvey, Wayne; Haque, Inam; Packard, Newton; Ng, Quintin; Ispirian, Julie Y.; Waian, Christopher; Janes, Drew

    2008-01-01

    A document discusses the creation of a high-voltage power supply (HVPS) that is able to contain voltages up to -20 kV, keep electrical field strengths to below 200 V/mil (approximately equal to 7.87 kV/mm), and can provide a 200-nanosecond rise/fall time focus modulator swinging between cathode potential of 16.3 kV and -19.3 kV. This HVPS can protect the 95-GHz, pulsed extended interaction klystron (EIK) from arcs/discharges from all sources, including those from within the EIK fs vacuum envelope. This innovation has a multi-winding pulse transformer design, which uses new winding techniques to provide the same delays and rise/fall times (less than 10 nanoseconds) at different potential levels ranging from -20 kV to -16 kV. Another feature involves a high-voltage printed-wiring board that was corona-free at -20 kV DC with a 3- kV AC swing. The corona-free multilayer high-voltage board is used to simulate fields of less than 200 V/mil (approximately equal to 7.87 kV/mm) at 20 kV DC. Drive techniques for the modulator FETs (field-effect transistors) (four to 10 in a series) were created to change states (3,000-V swing) without abrupt steps, while still maintaining required delays and transition times. The packing scheme includes a potting mold to house a ten-stage modulator in the space that, in the past, only housed a four-stage modulator. Problems keeping heat down were solved using aluminum oxide substrate in the high-voltage section to limit temperature rise to less than 10 while withstanding -20 kV DC voltage and remaining corona-free.

  3. A G-band terahertz monolithic integrated amplifier in 0.5-μm InP double heterojunction bipolar transistor technology

    Science.gov (United States)

    Ou-Peng, Li; Yong, Zhang; Rui-Min, Xu; Wei, Cheng; Yuan, Wang; Bing, Niu; Hai-Yan, Lu

    2016-05-01

    Design and characterization of a G-band (140-220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140-190 GHz respectively. The saturation output powers are -2.688 dBm at 210 GHz and -2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. Project supported by the National Natural Science Foundation of China (Grant No. 61501091) and the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant Nos. ZYGX2014J003 and ZYGX2013J020).

  4. Development of 3 kW at 325 MHz solid-state RF power amplifier using four power amplifier modules

    Science.gov (United States)

    Ramarao, B. V.; Sonal, S.; Mishra, J. K.; Pande, M.; Singh, P.; Kumar, G.; Mukherjee, J.

    2014-01-01

    A high power solid-state RF power amplifier of 3 kW at 325 MHz has been developed using only four RF power amplifier modules of 850 W power output each. The design and characterization of RF power modules have been presented. A four way Wilkinson power combiner adds the output of four power amplifier modules with a total transmission loss of less than 6%. The combined power amplifier has a power gain of 20.2 dB at 1-dB compression point, and the corresponding output power is 2.8 kW at 325 MHz. The drain efficiency of the power amplifier is 65.3% at 3 kW. All the harmonics of this amplifier are below -40 dBc. The amplifier has better characteristics like fewer numbers of active devices per kilo watt, high efficiency, high gain, and ruggedness etc for RF accelerator applications.

  5. Electroabsorption modulated semiconductor optical amplifier monolithically integrated with spot-size converters

    Science.gov (United States)

    Hou, Lianping; Zhu, Hongliang; Zhou, Fan; Wang, Baojun; Bian, Jing; Wang, Wei

    2006-02-01

    We have demonstrated an electroabsorption modulator (EAM) and semiconductor optical amplifier (SOA) monolithically integrated with novel dual-waveguide spot-size converters (SSCs) at the input and output ports for low-loss coupling to planar light-guide circuit silica waveguide or cleaved single-mode optical fiber. The device is fabricated by means of selective-area MOVPE growth (SAG), quantum well intermixing (QWI) and asymmetric twin waveguide (ATG) technologies with only three steps low-pressure MOVPE growth. For the device structure, in SOA/EAM section, double ridge structure was employed to reduce the EAM capacitances and enable high bit-rate operation. In the SSC sections, buried ridge stripe (BRS) were incorporated. Such a combination of ridge, ATG and BRS structure is reported for the first time in which it can take advantage of both easy processing of ridge structure and the excellent mode characteristic of BRS. At the wavelength range of 1550-1600 nm, lossless operation with extinction ratios of 25 dB DC and more than 10 GHz 3-dB bandwidth is successfully achieved. The beam divergence angles of the input and output ports of the device are as small as 8.0°×12.6°, resulting in 3.0 dB coupling loss with cleaved single-mode optical fiber.

  6. Challenges and Techniques in Measurements of Noise, Cryogenic Noise and Power in Millimeter-Wave and Submillimeter-Wave Amplifiers

    Science.gov (United States)

    Samoska, Lorene

    2014-01-01

    We will present the topic of noise measurements, including cryogenic noise measurements, of Monolithic Microwave Integrated Circuit (MMIC) and Sub-Millimeter-Wave Monolithic Microwave Integrated Circuit (S-MMIC) amplifiers, both on-wafer, and interfaced to waveguide modules via coupling probes. We will also present an overview of the state-of-the-art in waveguide probe techniques for packaging amplifier chips, and discuss methods to obtain the lowest loss packaging techniques available to date. Linearity in noise measurements will be discussed, and experimental methods for room temperature and cryogenic noise measurements will be presented. We will also present a discussion of power amplifier measurements for millimeter-wave and submillimeter-wave amplifiers, and the tools and hardware needed for this characterization.

  7. A Sampled Grating DBR Laser Monolithically Integrated by Using SOAs with 22 mW Output Power and 51 ITU 100 GHz Channels over 43 nm

    Science.gov (United States)

    Liu, Yang; Ye, Nan; Zhou, Dai-Bing; Wang, Bao-Jun; Pan, Jiao-Qing; Zhao, Ling-Juan; Wang, Wei

    2011-02-01

    A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43 nm from 1514.05 nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 mW for all output wavelengths, is successfully demonstrated.

  8. Power amplifiers in CMOS technology : a contribution to power amplifier theory and techniques

    NARCIS (Netherlands)

    Acar, Mustafa

    2011-01-01

    In order to meet the demands from the market on cheaper, miniaturized mobile communications devices realization of RF power amplifiers(PAs) in the mainstream CMOS technology is essential. In general, CMOS PAs require high supply-voltage to decrease the matching network losses and for high output pow

  9. Series-Tuned High Efficiency RF-Power Amplifiers

    DEFF Research Database (Denmark)

    Vidkjær, Jens

    2008-01-01

    An approach to high efficiency RF-power amplifier design is presented. It addresses simultaneously efficiency optimization and peak voltage limitations when transistors are pushed towards their power limits.......An approach to high efficiency RF-power amplifier design is presented. It addresses simultaneously efficiency optimization and peak voltage limitations when transistors are pushed towards their power limits....

  10. Monolithically integrated quantum dot optical modulator with semiconductor optical amplifier for thousand and original band optical communication

    Science.gov (United States)

    Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Matsumoto, Atsushi; Kawanishi, Tetsuya

    2016-04-01

    A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed with T-band (1.0 µm waveband) and O-band (1.3 µm waveband) QD optical gain materials for Gbps-order, high-speed optical data generation. The insertion loss due to coupling between the device and the optical fiber was effectively compensated for by the SOA section. It was also confirmed that the monolithic QD-OGM/SOA device enabled >4.8 Gbps optical data generation with a clear eye opening in the T-band. Furthermore, we successfully demonstrated error-free 4.8 Gbps optical data transmissions in each of the six wavelength channels over a 10-km-long photonic crystal fiber using the monolithic QD-OGM/SOA device in multiple O-band wavelength channels, which were generated by the single QD gain chip. These results suggest that the monolithic QD-OGM/SOA device will be advantageous in ultra-broadband optical frequency systems that utilize the T+O-band for short- and medium-range optical communications.

  11. Development of 3 kW at 325 MHz solid-state RF power amplifier using four power amplifier modules

    Energy Technology Data Exchange (ETDEWEB)

    Ramarao, B.V., E-mail: bvram@barc.gov.in [Ion Accelerator Development Division, Bhabha Atomic Research Center, Mumbai 400085 (India); Sonal, S.; Mishra, J.K.; Pande, M.; Singh, P. [Ion Accelerator Development Division, Bhabha Atomic Research Center, Mumbai 400085 (India); Kumar, G.; Mukherjee, J. [Indian Institute of Technology, Powai, Mumbai 400076 (India)

    2014-01-21

    A high power solid-state RF power amplifier of 3 kW at 325 MHz has been developed using only four RF power amplifier modules of 850 W power output each. The design and characterization of RF power modules have been presented. A four way Wilkinson power combiner adds the output of four power amplifier modules with a total transmission loss of less than 6%. The combined power amplifier has a power gain of 20.2 dB at 1-dB compression point, and the corresponding output power is 2.8 kW at 325 MHz. The drain efficiency of the power amplifier is 65.3% at 3 kW. All the harmonics of this amplifier are below −40 dBc. The amplifier has better characteristics like fewer numbers of active devices per kilo watt, high efficiency, high gain, and ruggedness etc for RF accelerator applications. -- Highlights: • High gain power amplifier, power gain at 20 dB. • High efficiency amplifier, efficiency >65%. • Minimum number of modules per kilo watt power output. • Heat sink with modules on both side, high density.

  12. Optimal Relay Power Allocation for Amplify-and-Forward Relay Networks with Non-linear Power Amplifiers

    OpenAIRE

    Zhang, Chao; Ren, Pinyi; Peng, Jingbo; Wei, Guo; Du, Qinghe; Wang, Yichen

    2011-01-01

    In this paper, we propose an optimal relay power allocation of an Amplify-and-Forward relay networks with non-linear power amplifiers. Based on Bussgang Linearization Theory, we depict the non-linear amplifying process into a linear system, which lets analyzing system performance easier. To obtain spatial diversity, we design a complete practical framework of a non-linear distortion aware receiver. Consider a total relay power constraint, we propose an optimal power allocation scheme to maxim...

  13. Modeling and design techniques for RF power amplifiers

    CERN Document Server

    Raghavan, Arvind; Laskar, Joy

    2008-01-01

    The book covers RF power amplifier design, from device and modeling considerations to advanced circuit design architectures and techniques. It focuses on recent developments and advanced topics in this area, including numerous practical designs to back the theoretical considerations. It presents the challenges in designing power amplifiers in silicon and helps the reader improve the efficiency of linear power amplifiers, and design more accurate compact device models, with faster extraction routines, to create cost effective and reliable circuits.

  14. GaN-based Power amplifiers for microwave applications

    Directory of Open Access Journals (Sweden)

    Jorge Julián Moreno-Rubio

    2016-01-01

    Full Text Available This paper presents a discussion about the design strategies of different kind of power amplifiers for RF/Microwave appli- cations, such as the tuned load power amplifier, class F, class F-1 and Doherty. Furthermore, it is shown the continuous wave characterization of the amplifiers above mentioned. A comparison between the obtained results, in terms of gain, efficiency and output power is presented.

  15. Switching-mode Audio Power Amplifiers with Direct Energy Conversion

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a new class of switching-mode audio power amplifiers, which are capable of direct energy conversion from the AC mains to the audio output. They represent an ultimate integration of a switching-mode power supply and a Class D audio power amplifier, where the intermediate DC bus...

  16. Switching-mode Audio Power Amplifiers with Direct Energy Conversion

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a new class of switching-mode audio power amplifiers, which are capable of direct energy conversion from the AC mains to the audio output. They represent an ultimate integration of a switching-mode power supply and a Class D audio power amplifier, where the intermediate DC bus...... has been replaced with a high frequency AC link. When compared to the conventional Class D amplifiers with a separate DC power supply, the proposed single conversion stage amplifier provides simple and compact solution with better efficiency and higher level of integration, leading to reduced...

  17. Particle detector tunable monolithic Semi-Gaussian shaping filter based on transconductance amplifiers

    Science.gov (United States)

    Noulis, T.; Deradonis, C.; Siskos, S.; Sarrabayrouse, G.

    2008-05-01

    An IC semi-Gaussian shaper architecture for X-rays silicon strip detectors is presented. The specific structure is based on operational transconductance amplifiers (OTAs) and was implemented using an alternative design technique. The shaper was designed and fabricated in a 0.35 μm process by Austria Mikro Systeme and provides continuous variable operating bandwidth in a relatively low-frequency region, capability that indicates it as an optimum selection for a variety of readout applications. Analysis is supported by measurement results confirming the advantageous shaping filter performance. The circuit appears to be low power providing 530 μW power dissipation, while the output noise performance is 167 μV (rms) for an operating bandwidth of 260 kHz. Extensive experimental results concerning the total harmonic distortion and the dynamic range of the circuit also confirm its satisfactory performance.

  18. High Efficiency Microwave Power Amplifier: From the Lab to Industry

    Science.gov (United States)

    Sims, William Herbert, III; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Since the beginnings of space travel, various microwave power amplifier designs have been employed. These included Class-A, -B, and -C bias arrangements. However, shared limitation of these topologies is the inherent high total consumption of input power associated with the generation of radio frequency (RF)/microwave power. The power amplifier has always been the largest drain for the limited available power on the spacecraft. Typically, the conversion efficiency of a microwave power amplifier is 10 to 20%. For a typical microwave power amplifier of 20 watts, input DC power of at least 100 watts is required. Such a large demand for input power suggests that a better method of RF/microwave power generation is required. The price paid for using a linear amplifier where high linearity is unnecessary includes higher initial and operating costs, lower DC-to-RF conversion efficiency, high power consumption, higher power dissipation and the accompanying need for higher capacity heat removal means, and an amplifier that is more prone to parasitic oscillation. The first use of a higher efficiency mode of power generation was described by Baxandall in 1959. This higher efficiency mode, Class-D, is achieved through distinct switching techniques to reduce the power losses associated with switching, conduction, and gate drive losses of a given transistor.

  19. An RF Power Amplifier in a Digital CMOS Process

    DEFF Research Database (Denmark)

    Nielsen, Per Asbeck; Fallesen, Carsten

    2002-01-01

    A two stage class B power amplifier for 1.9 GHz is presented. The amplifier is fabricated in a standard digital EPI-CMOS process with low resistivity substrate. The measured output power is 29 dBm in a 50 Omega load. A design method to find the large signal parameters of the output transistor...

  20. Efficient Power Amplifier for Motor Control

    Science.gov (United States)

    Brown, R. J.

    1986-01-01

    Pulse-width-modulated amplifier supplies high current as efficiently as low current needed for starting and running motor. Key to efficiency of motor-control amplifier is V-channel metal-oxide/semiconductor transistor Q1. Device has low saturation resistance. However, has large gate input capacitance and small margin between its turn-on voltage and maximum allowable gate-to-source voltage. Circuits for output stages overcome limitations of VMOS device.

  1. High-Performance Solid-State W-Band Power Amplifiers

    Science.gov (United States)

    Gaier, Todd; Samoska, Lorene; Wells, Mary; Ferber, Robert; Pearson, John; Campbell, April; Peralta, Alejandro; Swift, Gerald; Yocum, Paul; Chung, Yun

    2003-01-01

    The figure shows one of four solid-state power amplifiers, each capable of generating an output power greater than or equal to 240 mW over one of four overlapping frequency bands from 71 to 106 GHz. (The bands are 71 to 84, 80 to 92, 88 to 99, and 89 to 106 GHz.) The amplifiers are designed for optimum performance at a temperature of 130 K. These amplifiers were developed specifically for incorporation into frequency-multiplier chains in local oscillators in a low-noise, far-infrared receiving instrument to be launched into outer space to make astrophysical observations. The designs of these amplifiers may also be of interest to designers and manufacturers of terrestrial W-band communication and radar systems. Each amplifier includes a set of six high-electron-mobility transistor (HEMT) GaAs monolithic microwave integrated-circuit (MMIC) chips, microstrip cavities, and other components packaged in a housing made from A-40 silicon-aluminum alloy. This alloy was chosen because, for the original intended spacecraft application, it offers an acceptable compromise among the partially competing requirements for high thermal conductivity, low mass, and low thermal expansion. Problems that were solved in designing the amplifiers included designing connectors and packages to fit the available space; designing microstrip signal-power splitters and combiners; matching of impedances across the frequency bands; matching of the electrical characteristics of those chips installed in parallel power-combining arms; control and levelling of output power across the bands; and designing the MMICs, microstrips, and microstrip cavities to suppress tendencies toward oscillation in several modes, both inside and outside the desired frequency bands.

  2. Low power RF amplifier circuit for ion trap applications

    Science.gov (United States)

    Noriega, J. R.; García-Delgado, L. A.; Gómez-Fuentes, R.; García-Juárez, A.

    2016-09-01

    A low power RF amplifier circuit for ion trap applications is presented and described. The amplifier is based on a class-D half-bridge amplifier with a voltage mirror driver. The RF amplifier is composed of an RF class-D amplifier, an envelope modulator to ramp up the RF voltage during the ion analysis stage, a detector or amplitude demodulation circuit for sensing the output signal amplitude, and a feedback amplifier that linearizes the steady state output of the amplifier. The RF frequency is set by a crystal oscillator and the series resonant circuit is tuned to the oscillator frequency. The resonant circuit components have been chosen, in this case, to operate at 1 MHz. In testings, the class-D stage operated at a maximum of 78 mW at 1.1356 MHz producing 225 V peak.

  3. Magnetic Bearing Amplifier Output Power Filters for Flywheel Systems

    Science.gov (United States)

    Lebron-Velilla, Ramon C.; Jansen, Ralph H.; Palazzolo, Alan; Thomas, Erwin; Kascak, Peter E.; Birchenough, Arthur G.; Dever, Timothy P.

    2003-01-01

    Five power filters and two types of power amplifiers were tested for use with active magnetic bearings for flywheel applications. Filter topologies included low pass filters and low pass filters combined with trap filters at the PWM switching frequency. Two state and three state PWM amplifiers were compared. Each system was evaluated based on current magnitude at the switching frequency, voltage magnitude at 500 kHz, and power consumption. The base line system was a two state amplifier without a power filter. The recommended system is a three state power amplifier with a 50 kHz low pass filter and a 27 kHz trap filter. This system uses 5.57 W. It reduces the switching current by an order of magnitude and the 500 kHz voltage by two orders of magnitude. The relative power consumption varied depending on the test condition between 60 to 130 percent of the baseline.

  4. Multi Carrier Modulation Audio Power Amplifier with Programmable Logic

    DEFF Research Database (Denmark)

    Christiansen, Theis; Andersen, Toke Meyer; Knott, Arnold

    2009-01-01

    While switch-mode audio power amplifiers allow compact implementations and high output power levels due to their high power efficiency, they are very well known for creating electromagnetic interference (EMI) with other electronic equipment. To lower the EMI of switch-mode (class D) audio power a...

  5. High power solid state rf amplifier for proton accelerator.

    Science.gov (United States)

    Jain, Akhilesh; Sharma, Deepak Kumar; Gupta, Alok Kumar; Hannurkar, P R

    2008-01-01

    A 1.5 kW solid state rf amplifier at 352 MHz has been developed and tested at RRCAT. This rf source for cw operation will be used as a part of rf system of 100 MeV proton linear accelerator. A rf power of 1.5 kW has been achieved by combining output power from eight 220 W rf amplifier modules. Amplifier modules, eight-way power combiner and divider, and directional coupler were designed indigenously for this development. High efficiency, ease of fabrication, and low cost are the main features of this design.

  6. PHEMT Distributed Power Amplifier Adopting Broadband Impedance Transformer

    DEFF Research Database (Denmark)

    Narendra, K.; Limiti, E.; Paoloni, C.

    2013-01-01

    A non-uniform drain line distributed power amplifier (DPA) employing a broadband impedance transformer is presented. The DPA is based on GaAs PHEMT technology. The impedance transformer employs asymmetric coupled lines and transforms a low output impedance of the amplifier to a standard 50 Ω...

  7. Energy Efficient and Compact RF High-Power Amplifiers

    NARCIS (Netherlands)

    Calvillo Cortés, D.A.

    2014-01-01

    The main objectives of this thesis are to improve the energy efficiency and physical form-factor of high-power amplifiers in base station applications. As such, the focus of this dissertation is placed on the outphasing amplifier concept, which can offer high-efficiency, good linearity and excellent

  8. A Power Efficient Audio Amplifier Combining Switching and Linear Techniques

    NARCIS (Netherlands)

    van der Zee, Ronan A.R.; van Tuijl, Adrianus Johannes Maria

    1998-01-01

    Integrated Class D audio amplifiers are very power efficient, but require an external filter which prevents further integration. Also due to this filter, large feedback factors are hard to realise, so that the load influences the distortion- and transfer characteristics. The amplifier presented in

  9. A Power Efficient Audio Amplifier Combining Switching and Linear Techniques

    NARCIS (Netherlands)

    van der Zee, Ronan A.R.; van Tuijl, Adrianus Johannes Maria

    1998-01-01

    Integrated Class D audio amplifiers are very power efficient, but require an external filter which prevents further integration. Also due to this filter, large feedback factors are hard to realise, so that the load influences the distortion- and transfer characteristics. The amplifier presented in t

  10. Dual Band High Efficiency Power Amplifier Based on CRLH Lines

    Directory of Open Access Journals (Sweden)

    D. Segovia-Vargas

    2009-12-01

    Full Text Available In this paper we propose the use of Composite Right/Left Hand (CRLH and Extended Composite Right/Left Hand (ECRLH transmission lines for the design of dual band high efficiency power amplifiers working in CE class. The harmonic termination can be synthesized using the meta-lines is particularly suitable for CE class amplifiers, which have a termination not as sensitive to the third harmonic as F class amplifier. This paper presents the design procedure and the design equations. The nonlinear phase response of a CRLH and ECRLH transmission line has been utilized to design arbitrary dual-band amplifiers.

  11. A Sampled Grating DBR Laser Monolithically Integrated by Using SOAs with 22mW Output Power and 51 ITU 100 GHz Channels over 43 nm

    Institute of Scientific and Technical Information of China (English)

    LIU Yang; YE Nan; ZHOU Dai-Bing; WANG Bao-Jun; PAN Jiao-Qing; ZHAO Ling-Juan; WANG Wei

    2011-01-01

    @@ A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43nm from 1514.05 nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 mW for all output wavelengths, is successfully demonstrated.%A sampled grating distributed Bragg reflector (SG-DBR) laser monolithically integrated with semiconductor optical amplifiers (SOAs), which has a tuning range over 43nm from 1514.05nm to 1557.4 nm covering 49 continuous and totally 51 ITU 100 GHz standard channels and an output power more than 22 m W for all output wavelengths,is successfully demonstrated.

  12. Hard Horn Design for Quasi-Optical Power Combining Using Solid-State Power Amplifiers

    Science.gov (United States)

    Pickens, W. S.; Epp, L. W.; Hoppe, D. J.

    2004-02-01

    In recent years, there has been significant interest in the use of corrugated, periodic structures to control the wave impedance of a given surface. It has been shown [1] that a quasi-transverse-electromagnetic (TEM) wave can be excited in a waveguide by correctly choosing the impedance at the guide wall. This correctly chosen impedance is referred to as the hard boundary condition. We have taken advantage of this property of the so-called "hard" guide to attempt to create a spatial power combiner/splitter that couples to an array of microstrip patch antennas feeding a bank of monolithic microwave integrated circuit (MMIC) power amplifiers. The hard horn described here employs longitudinal corrugations filled with a low-loss dielectric material along the vertical walls to achieve the hard boundary condition. We believe the use of dielectric-filled corrugations will improve the insertion loss performance over that of a hard guide using dielectric slabs bonded to the guide wall. Additionally, the horn is tapered to its maximum aperture along a cosine curve in order to improve return loss performance. Included in this article is a discussion of the fabrication process of prototype hard horns, measurements of a hard horn prototype, and preliminary modal analysis results.

  13. PULSE MODULATION POWER AMPLIFIER WITH ENHANCED CASCADE CONTROL METHOD

    DEFF Research Database (Denmark)

    1998-01-01

    A digital switching power amplifier with Multivariable Enhanced Cascade Controlled (MECC) includes a modulator, a switching power stage and a low pass filter. In the first preferred embodiment an enhanced cascade control structure local to the switching power stage is added, characterised by havi...... and feedback path A to determine stable self-oscillating conditions. An implemented 250W example MECC digital power amplifier has proven superior performance in terms of audio performance (0.005 % distortion, 115 dB dynamic range) and efficiency (92 %).......A digital switching power amplifier with Multivariable Enhanced Cascade Controlled (MECC) includes a modulator, a switching power stage and a low pass filter. In the first preferred embodiment an enhanced cascade control structure local to the switching power stage is added, characterised by having...

  14. 1.55 Micron High Peak Power Fiber Amplifier Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this proposal, we propose to demonstrate and build a 1.55 micron single frequency high energy and high peak power fiber amplifier by developing an innovative...

  15. 1.55 Micron High Peak Power Fiber Amplifier Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this proposal, we propose to demonstrate and build a 1.55 micron single frequency high energy and high peak power fiber amplifier by developing an innovative...

  16. Cryogenic cooling for high power laser amplifiers

    Directory of Open Access Journals (Sweden)

    Perin J.P.

    2013-11-01

    Full Text Available Using DPSSL (Diode Pumped Solid State Lasers as pumping technology, PW-class lasers with enhanced repetition rates are developed. Each of the Yb YAG amplifiers will be diode-pumped at a wavelength of 940 nm. This is a prerequisite for achieving high repetition rates (light amplification duration 1 millisecond and repetition rate 10 Hz. The efficiency of DPSSL is inversely proportional to the temperature, for this reason the slab amplifier have to be cooled at a temperature in the range of 100 K–170 K with a heat flux of 1 MW*m−2. This paper describes the thermo-mechanical analysis for the design of the amplification laser head, presents a preliminary proposal for the required cryogenic cooling system and finally outlines the gain of cryogenic operation for the efficiency of high pulsed laser.

  17. On Instantaneous Power Dissipation in Class B Amplifier

    Directory of Open Access Journals (Sweden)

    Hristo Zhivomirov

    2014-08-01

    Full Text Available The present paper describes the analysis of the instantaneous power dissipation by the two active components in a class B power amplifier. Attention is paid to restrictions of the instantaneous power dissipation relations in reference literature, and the consequences of their misuse. A new generalized equation that takes into account the power dissipated by the two active devices is proposed. The theoretical statement is substantiated by Matlab® numeric computation and visualization, Cadence OrCAD® simulations and measurements of a real-world audio power amplifier performed by NI USB-6211 measurement complex.

  18. Thermally induced nonlinear mode coupling in high power fiber amplifiers

    DEFF Research Database (Denmark)

    Johansen, Mette Marie; Hansen, Kristian Rymann; Alkeskjold, Thomas T.;

    2013-01-01

    Thermally induced nonlinear mode coupling leads to transverse mode instability (TMI) in high power fiber amplifiers. A numerical model including altering mode profiles from thermal effects and waveguide perturbations predicts a TMI threshold of ~200W.......Thermally induced nonlinear mode coupling leads to transverse mode instability (TMI) in high power fiber amplifiers. A numerical model including altering mode profiles from thermal effects and waveguide perturbations predicts a TMI threshold of ~200W....

  19. Thermal Effects in High-Power Fiber Amplifiers

    DEFF Research Database (Denmark)

    Hansen, Kristian Rymann; Lægsgaard, Jesper

    2011-01-01

    The effect of temperature gradients in Yb-doped fiber amplifiers is studied numerically. We investigate the dependence of the mode area on the signal power, and compare forward and backward pumping schemes.......The effect of temperature gradients in Yb-doped fiber amplifiers is studied numerically. We investigate the dependence of the mode area on the signal power, and compare forward and backward pumping schemes....

  20. 2250-MHz High Efficiency Microwave Power Amplifier (HEMPA)

    Science.gov (United States)

    Sims, W. Herbert; Bell, Joseph L. (Technical Monitor)

    2001-01-01

    Tnis paper will focus on developing an exotic switching technique that enhances the DC-to-RF conversion efficiency of microwave power amplifiers. For years, switching techniques implemented in the 10 kHz to 30 MHz region have resulted in DC-to-RF conversion efficiencies of 90-95-percent. Currently amplifier conversion efficiency, in the 2-3 GHz region approaches, 10-20-percent. Using a combination of analytical modeling and hardware testing, a High Efficiency Microwave Power Amplifier was built that demonstrated conversion efficiencies four to five times higher than current state of the art.

  1. Introduction to RF power amplifier design and simulation

    CERN Document Server

    Eroglu, Abdullah

    2015-01-01

    Introduction to RF Power Amplifier Design and Simulation fills a gap in the existing literature by providing step-by-step guidance for the design of radio frequency (RF) power amplifiers, from analytical formulation to simulation, implementation, and measurement. Featuring numerous illustrations and examples of real-world engineering applications, this book:Gives an overview of intermodulation and elaborates on the difference between linear and nonlinear amplifiersDescribes the high-frequency model and transient characteristics of metal-oxide-semiconductor field-effect transistorsDetails activ

  2. The Gain Dependence of the Power Transient in Raman Amplifier

    Institute of Scientific and Technical Information of China (English)

    Zheng Lei; Zhang Jiahong; Chen Zhangyuan; Wu Deming; Xu Anshi

    2003-01-01

    It is observed that the amplitude of the power transient overshoot depends on the gain of the amplifier when the input signal powers are the same. The other system parameters, such as the input pump power and fiber length, have no effects on it.

  3. Multi Carrier Modulator for Switch-Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Pfaffinger, Gerhard; Andersen, Michael Andreas E.

    2008-01-01

    While switch-mode audio power amplifiers allow compact implementations and high output power levels due to their high power efficiency, they are very well known for creating electromagnetic interference (EMI) with other electronic equipment, in particular radio receivers. Lowering the EMI of swit...

  4. High Power Performance of Rod Fiber Amplifiers

    DEFF Research Database (Denmark)

    Johansen, Mette Marie; Michieletto, Mattia; Kristensen, Torben

    2015-01-01

    An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W.......An improved version of the DMF rod fiber is tested in a high power setup delivering 360W of stable signal power. Multiple testing degrades the fiber and transverse modal instability threshold from >360W to ~290W....

  5. Multi Carrier Modulation Audio Power Amplifier with Programmable Logic

    DEFF Research Database (Denmark)

    Christiansen, Theis; Andersen, Toke Meyer; Knott, Arnold

    2009-01-01

    While switch-mode audio power amplifiers allow compact implementations and high output power levels due to their high power efficiency, they are very well known for creating electromagnetic interference (EMI) with other electronic equipment. To lower the EMI of switch-mode (class D) audio power...... for performance and out of band spectral amplitudes. The basic principle in MCM is to use programmable logic to combine two or more Pulse Width Modulated (PWM) audio signals at different switching frequencies. In this way the out of band spectrum will be lowered compared with conventional class D amplifiers...

  6. Phase noise measurement of high-power fiber amplifiers

    Institute of Scientific and Technical Information of China (English)

    Hu Xiao; Xiaolin Wang; Yanxing Ma; Bing He; Pu Zhou; Jun Zhou; Xiaojun Xu

    2011-01-01

    We measure the phase fluctuation in a high-power fiber amplifier using a multi-dithering technique. Its fluctuation property is qualitatively analyzed by the power spectral density and integrated spectral density.Low frequency fluctuations caused by the environment are dominant in the phase fluctuations in an amplifier, whereas the high frequency components related to laser power affect the control bandwidth. The bandwidth requirement of the active phase-locking is calculated to be 300 Hz, 670 Hz, 1.6 kHz, and 3.9 kHz under the output power of 25,55, 125, and 180W, respectively. The approximately linear relationship between the control bandwidth and laser power needs to be further investigated.%@@ We measure the phase fluctuation in a high-power fiber amplifier using a multi-dithering technique.Its fluctuation property is qualitatively analyzed by the power spectral density and integrated spectral density.Low frequency fluctuations caused by the environment are dominant in the phase fluctuations in an am-plifier, whereas the high frequency components related to laser power affect the control bandwidth.The bandwidth requirement of the active phase-locking is calculated to be 300 Hz, 670 Hz, 1.6 kHz, and 3.9kHz under the output power of 25, 55, 125, and 180 W, respectively.The approximately linear relationship between the control bandwidth and laser power needs to be further investigated.

  7. Wideband high efficiency CMOS envelope amplifiers for 4G LTE handset envelope tracking RF power amplifiers

    OpenAIRE

    Hassan, Muhammad

    2012-01-01

    Fourth generation cellular networks offer performance similar to cable modems while allowing wide mobility. Although the use of orthogonal frequency division multiplexing in fourth generation increases its spectral efficiency but it also increases the peak-to-average power ratio of the transmitted signal. If a conventional power amplifier is used to transmit a high peak-to-average power ratio signal, then to meet the stringent linearity requirements, it will be operating 6 to 10 dB back-off f...

  8. Wideband LTE power amplifier with integrated novel analog pre-distorter linearizer for mobile wireless communications.

    Science.gov (United States)

    Uthirajoo, Eswaran; Ramiah, Harikrishnan; Kanesan, Jeevan; Reza, Ahmed Wasif

    2014-01-01

    For the first time, a new circuit to extend the linear operation bandwidth of a LTE (Long Term Evolution) power amplifier, while delivering a high efficiency is implemented in less than 1 mm2 chip area. The 950 µm × 900 µm monolithic microwave integrated circuit (MMIC) power amplifier (PA) is fabricated in a 2 µm InGaP/GaAs process. An on-chip analog pre-distorter (APD) is designed to improve the linearity of the PA, up to 20 MHz channel bandwidth. Intended for 1.95 GHz Band 1 LTE application, the PA satisfies adjacent channel leakage ratio (ACLR) and error vector magnitude (EVM) specifications for a wide LTE channel bandwidth of 20 MHz at a linear output power of 28 dBm with corresponding power added efficiency (PAE) of 52.3%. With a respective input and output return loss of 30 dB and 14 dB, the PA's power gain is measured to be 32.5 dB while exhibiting an unconditional stability characteristic from DC up to 5 GHz. The proposed APD technique serves to be a good solution to improve linearity of a PA without sacrificing other critical performance metrics.

  9. Wideband LTE power amplifier with integrated novel analog pre-distorter linearizer for mobile wireless communications.

    Directory of Open Access Journals (Sweden)

    Eswaran Uthirajoo

    Full Text Available For the first time, a new circuit to extend the linear operation bandwidth of a LTE (Long Term Evolution power amplifier, while delivering a high efficiency is implemented in less than 1 mm2 chip area. The 950 µm × 900 µm monolithic microwave integrated circuit (MMIC power amplifier (PA is fabricated in a 2 µm InGaP/GaAs process. An on-chip analog pre-distorter (APD is designed to improve the linearity of the PA, up to 20 MHz channel bandwidth. Intended for 1.95 GHz Band 1 LTE application, the PA satisfies adjacent channel leakage ratio (ACLR and error vector magnitude (EVM specifications for a wide LTE channel bandwidth of 20 MHz at a linear output power of 28 dBm with corresponding power added efficiency (PAE of 52.3%. With a respective input and output return loss of 30 dB and 14 dB, the PA's power gain is measured to be 32.5 dB while exhibiting an unconditional stability characteristic from DC up to 5 GHz. The proposed APD technique serves to be a good solution to improve linearity of a PA without sacrificing other critical performance metrics.

  10. Design and multi-objective optimization for a broad self-amplified 2-DOF monolithic mechanism

    Indian Academy of Sciences (India)

    THANH-PHONG DAO; SHYH-CHOUR HUANG

    2017-09-01

    This paper proposes a structural design and multi-objective optimization of a two-degree-of-freedom (DOF) monolithic mechanism. The mechanism is designed based on compliant mechanism with flexure hinge and is compact in size (126 mm by 107 mm). Unlike traditional one-lever mechanisms, a new doublelever mechanism is developed to increase the working travel amplification ratio of the monolithic mechanism. The ideal amplification ratio, the working travel, the statics and the dynamics of the mechanism are taken into consideration. The effects of design variables on the output responses such as the displacement and first natural frequency are investigated via finite-element analysis based on response surface methodology. The fuzzy-logicbased Taguchi method is then used to simultaneously optimize the displacement and the first natural frequency. Experimental validations are conducted to verify the optimal results, which are compared to those of the original design. On using a finite-element method, the validation results indicated that the displacement and frequency are enhanced by up to 12.47% and 33.27%, respectively, over those of the original design. The experiment results are in a good agreement with the simulations. It also revealed that the developed fuzzy-logic-based Taguchi method is an effectively systematic reasoning approach for optimizing the multiple quality characteristics of compliant mechanisms. It was noted that the working travel/displacement of the double-levermechanism is much larger than that of the traditional one-lever mechanism. It leads to the conclusion that the proposed mechanism has good performances for manipulations and positioning systems.

  11. Minimizing Crosstalk in Self Oscillating Switch Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Ploug, Rasmus Overgaard

    2012-01-01

    The varying switching frequencies of self oscillating switch mode audio amplifiers have been known to cause interchannel intermodulation disturbances in multi channel configurations. This crosstalk phenomenon has a negative impact on the audio performance. The goal of this paper is to present...... a method to minimize this phenomenon by improving the integrity of the various power distribution systems of the amplifier. The method is then applied to an amplifier built for this investigation. The results show that the crosstalk is suppressed with 30 dB, but is not entirely eliminated...

  12. High-power phase locking of a fiber amplifier array

    Science.gov (United States)

    Shay, T. M.; Baker, J. T.; Sanchez, A. D.; Robin, C. A.; Vergien, C. L.; Zeringue, C.; Gallant, D.; Lu, Chunte A.; Pulford, Benjamin; Bronder, T. J.; Lucero, Arthur

    2009-02-01

    We report high power phase locked fiber amplifier array using the Self-Synchronous Locking of Optical Coherence by Single-detector Electronic-frequency Tagging technique. We report the first experimental results for a five element amplifier array with a total locked power of more than 725-W. We will report on experimental measurements of the phase fluctuations versus time when the control loop is closed. The rms phase error was measured to be λ/60. Recent results will be reported. To the best of the authors' knowledge this is the highest fiber laser power to be coherently combined.

  13. Monolithically integrated quantum dot optical gain modulator with semiconductor optical amplifier for 10-Gb/s photonic transmission

    Science.gov (United States)

    Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya

    2015-03-01

    Short-range interconnection and/or data center networks require high capacity and a large number of channels in order to support numerous connections. Solutions employed to meet these requirements involve the use of alternative wavebands to increase the usable optical frequency range. We recently proposed the use of the T- and O-bands (Thousand band: 1000-1260 nm, Original band: 1260-1360 nm) as alternative wavebands because large optical frequency resources (>60 THz) can be easily employed. In addition, a simple and compact Gb/s-order high-speed optical modulator is a critical photonic device for short-range communications. Therefore, to develop an optical modulator that acts as a highfunctional photonic device, we focused on the use of self-assembled quantum dots (QDs) as a three-dimensional (3D) confined structure because QD structures are highly suitable for realizing broadband optical gain media in the T+O bands. In this study, we use the high-quality broadband QD optical gain to develop a monolithically integrated QD optical gain modulator (QD-OGM) device that has a semiconductor optical amplifier (QD-SOA) for Gb/s-order highspeed optical data generation in the 1.3-μm waveband. The insertion loss of the device can be compensated through the SOA, and we obtained an optical gain change of up to ~7 dB in the OGM section. Further, we successfully demonstrate a 10-Gb/s clear eye opening using the QD-OGM/SOA device with a clock-data recovery sequence at the receiver end. These results suggest that the monolithic QD-EOM/SOA is suitable for increasing the number of wavelength channels for smart short-range communications.

  14. Measurement and Modeling of the Transfer Function of a Monolithic SOA-EA 2R-Regenerator

    DEFF Research Database (Denmark)

    Christiansen, Lotte Jin; Öhman, Filip; Kjær, Rasmus

    2005-01-01

    We have measured steep power transfer characteristics with tunable threshold for a monolithic 2R-regenerator combining amplifying and absorbing sections. Modeling results explain the basic characteristics.......We have measured steep power transfer characteristics with tunable threshold for a monolithic 2R-regenerator combining amplifying and absorbing sections. Modeling results explain the basic characteristics....

  15. Design and Development of Monolithic Microwave Integrated Amplifiers and Coupling Circuits for Telecommunication Systems Applications

    Directory of Open Access Journals (Sweden)

    R. Makri

    2002-01-01

    quadrature coupler and a Wilkinson one in order to reduce size. Finally, a two stages low noise amplifier was designed with the use of H40 GaAs process in order the differences between the relevant designs to be explored. The key specifications for this MMIC LNA include operation at 10 GHz with a total gain of 17 dB while the noise figure is less than 1.5 dB.

  16. A 240W Monolithic Class-D Audio Amplifier Output Stage

    DEFF Research Database (Denmark)

    Nyboe, Flemming; Kaya, Cetin; Risbo, Lars

    2006-01-01

    A single-channel class-D audio amplifier output stage outputs 240W undipped into 4Omega 0.1% open-loop THD+N allows using the device in a fully-digital audio signal path with no feedback. The output current capability is plusmn18A and the part is fabricated in a 0.4mum/1.8mum high-voltage Bi...

  17. 5 Watt GaN HEMT Power Amplifier for LTE

    Directory of Open Access Journals (Sweden)

    K. Niotaki

    2014-04-01

    Full Text Available This work presents the design and implementation of a stand-alone linear power amplifier at 2.4 GHz with high output power. A GaN HEMT transistor is selected for the design and implementation of the power amplifier. The device exhibits a gain of 11.7 dB and a drain efficiency of 39% for an output power of 36.7 dBm at 2.4 GHz for an input power of 25dBm. The carrier to intermodulation ratio is better than 25 dB for a two tone input signal of 25 dBm of total power and a spacing of 5 MHz. The fabricated device is also tested with LTE input signals of different bandwidths (5MHz to 20MHz.

  18. Optical power equalization using Fabry-Perot semiconductor optical amplifier

    Institute of Scientific and Technical Information of China (English)

    Yun Ling; Kun Qiu; Wei Zhang; Ying Pang

    2006-01-01

    A novel scheme of optical power equalization based on Fabry-Perot semiconductor optical amplifier (FPSOA) is proposed. Because of the gain characteristic of FP-SOA, real-time controlling mechanism according to input optical power is aborted in the scheme. The simulations show that 10-dB pulse peak power variation can be clamped in less than i dB. The influences of injecting current, pulse periods, and pulse width are discussed.

  19. Multislice behavioral modeling based on envelope domain for power amplifiers

    Institute of Scientific and Technical Information of China (English)

    Wang Huadong; Bao Jingfu; Wu Zhengde

    2009-01-01

    An envelope domain multislice behavioral modeling is introduced. The tradition AM-AM and AM-PM characteristics of power amplifiers are extended to envelope domain and base-band filter is applied to distortion complex envelope signal for description of the envelope memory effect. Using traditional one and two-tone tests, the coefficients of nonlinear model and the FIR filter can be extracted. At last the model has been applied to a 10 W WCDMA power amplifier to predict its output signal. And simulation results show that the model output conforms very well to the traditional transistor level simulation results.

  20. Solid-state microwave high-power amplifiers

    CERN Document Server

    Sechi, Franco

    2009-01-01

    This practical resource offers expert guidance on the most critical aspects of microwave power amplifier design. This comprehensive book provides descriptions of all the major active devices, discusses large signal characterization, explains all the key circuit design procedures. Moreover you gain keen insight on the link between design parameters and technological implementation, helping you achieve optimal solutions with the most efficient utilization of available technologies. The book covers a broad range of essential topics, from requirements for high-power amplifiers, device models, phas

  1. Current-Driven Switch-Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Buhl, Niels Christian; Andersen, Michael A. E.

    2012-01-01

    The conversion of electrical energy into sound waves by electromechanical transducers is proportional to the current through the coil of the transducer. However virtually all audio power amplifiers provide a controlled voltage through the interface to the transducer. This paper is presenting...... a switch-mode audio power amplifier not only providing controlled current but also being supplied by current. This results in an output filter size reduction by a factor of 6. The implemented prototype shows decent audio performance with THD + N below 0.1 %....

  2. Design And Construction Of 300W Audio Power Amplifier For Classroom

    Directory of Open Access Journals (Sweden)

    Shune Lei Aung

    2015-07-01

    Full Text Available Abstract This paper describes the design and construction of 300W audio power amplifier for classroom. In the construction of this amplifier microphone preamplifier tone preamplifier equalizer line amplifier output power amplifier and sound level indicator are included. The output power amplifier is designed as O.C.L system and constructed by using Class B among many types of amplifier classes. There are two types in O.C.L system quasi system and complementary system. Between them the complementary system is used in the construction of 300W audio power amplifier. The Multisim software is utilized for the construction of audio power amplifier.

  3. High Power Combiner/Divider Design for Dual Band RF Power Amplifiers

    OpenAIRE

    Flattery, Kyle; Amin, Shoaib; Rönnow, Daniel; Mahamat, Yaya; Eroglu, Abdullah

    2015-01-01

    Design of low loss with an enhanced thermal profile power divider/combiner for high power dual-band Radio Frequency (RF) power amplifier applications is given. The practical implementation, low loss and substrate characteristics make this type of combiner ideal for high power microwave applications.  The combiner operational frequencies are chosen to operate at 900 MHz and 2.14 GHz, which are common frequencies for concurrent dual band RF power amplifiers. The analytical results are verified ...

  4. Spatial Power Combining Amplifier for Ground and Flight Applications

    Science.gov (United States)

    Velazco, J. E.; Taylor, M.

    2016-11-01

    Vacuum-tube amplifiers such as klystrons and traveling-wave tubes are the workhorses of high-power microwave radiation generation. At JPL, vacuum tubes are extensively used in ground and flight missions for radar and communications. Vacuum tubes use electron beams as the source of energy to achieve microwave power amplification. Such electron beams operate at high kinetic energies and thus require high voltages to function. In addition, vacuum tubes use compact cavity and waveguide structures that hold very intense radio frequency (RF) fields inside. As the operational frequency is increased, the dimensions of these RF structures become increasingly smaller. As power levels and operational frequencies are increased, the highly intense RF fields inside of the tubes' structures tend to arc and create RF breakdown. In the case of very high-power klystrons, electron interception - also known as body current - can produce thermal runaway of the cavities that could lead to the destruction of the tube. The high voltages needed to power vacuum tubes tend to require complicated and cumbersome power supplies. Consequently, although vacuum tubes provide unmatched high-power microwaves, they tend to arc, suffer from thermal issues, and require failure-prone high-voltage power supplies. In this article, we present a new concept for generating high-power microwaves that we refer to as the Spatial Power Combining Amplifier (SPCA). The SPCA is very compact, requires simpler, lower-voltage power supplies, and uses a unique power-combining scheme wherein power from solid-state amplifiers is coherently combined. It is a two-port amplifier and can be used inline as any conventional two-port amplifier. It can deliver its output power to a coaxial line, a waveguide, a feed, or to any microwave load. A key feature of this new scheme is the use of higher-order-mode microwave structures to spatially divide and combine power. Such higher-order-mode structures have considerably larger cross

  5. Monolithically integrated semiconductor optical amplifier and electroabsorption modulator with dual-waveguide spot-size converter input and output

    Science.gov (United States)

    Hou, Lianping; Zhu, Hongliang; Zhou, Fan; Wang, Lufeng; Bian, Jing; Wang, Wei

    2005-09-01

    We have demonstrated an electroabsorption modulator and semiconductor optical amplifier monolithically integrated with novel dual-waveguide spot-size converters (SSC) at the input and output ports for low-loss coupling to a planar light-guide circuit silica waveguide or cleaved single-mode optical fibre. The device was fabricated by means of selective-area MOVPE growth, quantum well intermixing and asymmetric twin waveguide technologies with only a three-step low-pressure MOVPE growth. For the device structure, in the SOA/EAM section, a double ridge structure was employed to reduce the EAM capacitances and enable high bit-rate operation. In the SSC sections, buried ridge structure (BRS) was incorporated. Such a combination of ridge, ATG and BRS structure is reported for the first time in which it can take advantage of easy processing of the ridge structure and the excellent mode characteristic of BRS. At the wavelength range of 1550-1600 nm, lossless operation with extinction ratios of 25 dB dc and more than 10 GHz 3 dB bandwidth is successfully achieved. The beam divergence angles of the input and output ports of the device are as small as 8.0° × 12.6°, resulting in 3.0 dB coupling loss with a cleaved single-mode optical fibre.

  6. Semiconductor optical amplifier monolithically integrated with an electroabsorption modulator and dual-waveguide spot-size converters

    Science.gov (United States)

    Hou, Lianping; Zhu, Hongliang; Wang, Baojun; Zhou, Fan; Wang, Lufeng; Bian, Jing; Wang, Wei

    2005-09-01

    We have demonstrated an electroabsorption modulator and semiconductor optical amplifier monolithically integrated with novel dual-waveguide spot-size converters (SSC) at the input and output ports for low-loss coupling to planar light-guide circuit silica waveguide or cleaved single-mode optical fiber. The device was fabricated by means of selective-area MOVPE growth, quantum well intermixing and asymmetric twin waveguide technologies with only a three steps low-pressure MOVPE growth. For the device structure, in SOA/EAM section, double ridge structure was employed to reduce the EAM capacitances and enable high bit-rate operation. In the SSC sections, buried ridge structure (BRS) were incorporated. Such combination of ridge, ATG and BRS structure is reported for the first time in which it can take advantage of easy processing of ridge structure and the excellent mode characteristic of BRS. At the wavelength range of 1550~1600nm, lossless operation with extinction ratios of 25 dB dc and more than 10 GHz 3-dB bandwidth is successfully achieved. The beam divergence angles of the input and output ports of the device are as small as 8.0°×12.6°, resulting in 3.0 dB coupling loss with cleaved single-mode optical fiber.

  7. Analysis of Power Amplifier Modeling Schemes for Crosscorrelation Predistorters

    NARCIS (Netherlands)

    Kokkeler, Andre B.J.

    2004-01-01

    Amplification of signals with fluctuating envelopes leads to distortion because of non-linear behavior of the Power Amplifier (PA). Digital Predistortion can counteract these non-linear effects. A crosscorrelation predistorter is a digital predistorter, based on the calculation of crosscorrelation f

  8. Dynamic deviation Volterra predistorter designed for linearizing power amplifiers

    OpenAIRE

    2011-01-01

    Polynomial models of predistorter combined by the "black box" principle have been considered. A Volterra model using one-dimensional dynamic deviation was proposed. An adaptive predistorter was synthesized for linearizing the Wiener–Hammerstein model of power amplifiers. Estimates of the linearization accuracy and a comparative analysis of predistorter models were also presented.

  9. Orbital performance of communication satellite microwave power amplifiers (MPAs)

    Science.gov (United States)

    Strauss, R.

    1993-01-01

    This paper presents background data on the performance of microwave power amplifiers (MPAs) used as transmitters in currently operating commercial communication satellites. Specifically aspects of two competing MPA types are discussed. These are well known TWTA (travelling wave tube amplifier) and the SSPA (solid state power amplifier). Extensive in-orbit data has been collected from over 2000 MPAs in 1991 and 1993. The study in 1991 invovlved 75 S/C (spacecraft) covering 463 S/C years. The 1993 'second-look' study encompassed a slightly different population of 72 S/C with 497 S/C years of operation. A surprising result of both studies was that SSPAs, although quite reliable, did not achieve the reliability of TWTAs were one-third more reliable in the 1993 study. This was at C-band with comparable power amplifiers, e.g. 6-16W of RF output power and similar gains. Data at K(sub u)-band is for TWTAs only since there are no SSPAs in the current S/C inventory. The other complementary result was that the projected failure rates used as S/C payload design guidelines were, on average, somewhat higher for TWTAs than the actual failure rates uncovered by this study. SSPA rates were as projected.

  10. Quantum dot amplifiers with high output power and low noise

    DEFF Research Database (Denmark)

    Berg, Tommy Winther; Mørk, Jesper

    2003-01-01

    Quantum dot semiconductor optical amplifiers have been theoretically investigated and are predicted to achieve high saturated output power, large gain, and low noise figure. We discuss the device dynamics and, in particular, show that the presence of highly inverted barrier states does not limit ...

  11. Maximally Flat Waveforms Operation of Class-F Power Amplifiers

    Directory of Open Access Journals (Sweden)

    V. Krizhanovski

    2001-04-01

    Full Text Available The requirements to output network's impedance on higher harmoniccomponents and appropriate input driving for formation maximally flatwaveforms of drain current and voltage were presented. Using suchwaveforms allows obtaining maximal efficiency and output powercapability of class-F power amplifiers.

  12. Multi Carrier Modulator for Switch-Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Pfaffinger, Gerhard; Andersen, Michael Andreas E.

    2008-01-01

    While switch-mode audio power amplifiers allow compact implementations and high output power levels due to their high power efficiency, they are very well known for creating electromagnetic interference (EMI) with other electronic equipment, in particular radio receivers. Lowering the EMI of switch......-mode audio power amplifiers while keeping the performance measures to excellent levels is therefore of high general interest. A modulator utilizing multiple carrier signals to generate a two level pulse train will be shown in this paper. The performance of the modulator will be compared in simulation...... to existing modulation topologies. The lower EMI as well as the preserved audio performance will be shown in simulation as well as in measurement results on a prototype....

  13. A 4-9 GHz 10 W wideband power amplifier

    Institute of Scientific and Technical Information of China (English)

    陈中子; 陈晓娟; 姚小江; 袁婷婷; 刘新宇; 李滨

    2009-01-01

    A 4-9 GHz wideband high power amplifier is designed and fabricated, which has demonstrated saturated output power of 10 W covering 6-8 GHz band, and above 6 W over the other band. This PA module uses a bal-ance configuration, and presents power gain of 7.3 ± 0.9 dB over the whole 4-9 GHz band and 39% power-added efficiency (PAE) at 8 GHz. Both the input and output VSWR are also excellent, which are bellow -10 dB.

  14. 10 Gbps Colorless Optical Source in Wavelength-Division Multiplexed Passive Optical Networks for Monolithic Integration of Deep-Ridge Waveguide Electroabsorption Modulator with Planar Buried-Heterostructure Semiconductor Optical Amplifier

    Science.gov (United States)

    Kim, Dong Churl; Kim, Ki Soo; Kim, Hyun-Soo; Choi, Byung-Seok; Kwon, O.-Kyun

    2012-05-01

    For the 10 Gbps colorless optical source in wavelength-division multiplexed passive optical networks (WDM-PONs), we have fabricated a semiconductor optical amplifier-reflective electorabsorption modulator (SOA-REAM) by monolithic integration of deep-ridge waveguide REAM (DRW-REAM) with planar buried-heterostructure (PBH) SOA using a PNP-current blocking layer. The SOA-REAM has a spot-size convertor for easy fiber coupling. Using a butterfly module with an SMA connector, we have packaged the SOA-REAM. At a -10 dBm input power of 1550 nm, the saturation output power is about 6 dBm. At 10.7 Gbps, we can obtain clear eye diagrams, and the power penalty at 10-9 bit-error rate (BER) after 20 km transmission is less than 1 dB over 35 nm.

  15. Investigation on Satellite-borne High-power Solid-state Power Amplifier Technology and Experiment

    OpenAIRE

    Wu Xiao-po; Zhao Hai-yang; Xi Song-tao

    2014-01-01

    Based on the research and development efforts of satellite-borne lumped solid-state transmitters, the design of a satellite-borne high-power microwave amplifier module is introduced. Focusing on satellite-borne applications, aspects of the high-power density thermal design, multipactor proof design, EMC design and so on, which are critical technologies for a solid-state power amplifier, are discussed. Subsequently, experiments are used to verify the concept.

  16. Investigation on Satellite-borne High-power Solid-state Power Amplifier Technology and Experiment

    Directory of Open Access Journals (Sweden)

    Wu Xiao-po

    2014-06-01

    Full Text Available Based on the research and development efforts of satellite-borne lumped solid-state transmitters, the design of a satellite-borne high-power microwave amplifier module is introduced. Focusing on satellite-borne applications, aspects of the high-power density thermal design, multipactor proof design, EMC design and so on, which are critical technologies for a solid-state power amplifier, are discussed. Subsequently, experiments are used to verify the concept.

  17. Power Efficiency Improvements through Peak-to-Average Power Ratio Reduction and Power Amplifier Linearization

    Directory of Open Access Journals (Sweden)

    Zhou G Tong

    2007-01-01

    Full Text Available Many modern communication signal formats, such as orthogonal frequency-division multiplexing (OFDM and code-division multiple access (CDMA, have high peak-to-average power ratios (PARs. A signal with a high PAR not only is vulnerable in the presence of nonlinear components such as power amplifiers (PAs, but also leads to low transmission power efficiency. Selected mapping (SLM and clipping are well-known PAR reduction techniques. We propose to combine SLM with threshold clipping and digital baseband predistortion to improve the overall efficiency of the transmission system. Testbed experiments demonstrate the effectiveness of the proposed approach.

  18. Multisine Decomposition Algorithm for RF Power Amplifier Characterization

    DEFF Research Database (Denmark)

    Palmisano, Davide; Galasso, Andrea; Tafuri, Felice Francesco;

    2015-01-01

    This paper presents an algorithm for the generation of a multisine signal capable of accurately mimicking bandwidth and first order statistics such as the probability density function and the peak-to-average power ratio (PAPR) of an arbitrary digitally modulated signal. The implemented algorithm...... outperforms state-of-the-art multisine design procedures by proposing a solution capable of achieving an arbitrarily low PAPR error with respect to the digital signal being decomposed. This innovative step enables a fast multisine-based power amplifier characterization with results that closely match...... that obtained using the actual digital signal....

  19. Linear CMOS RF power amplifiers a complete design workflow

    CERN Document Server

    Ruiz, Hector Solar

    2013-01-01

    The work establishes the design flow for the optimization of linear CMOS power amplifiers from the first steps of the design to the final IC implementation and tests. The authors also focuses on design guidelines of the inductor's geometrical characteristics for power applications and covers their measurement and characterization. Additionally, a model is proposed which would facilitate designs in terms of transistor sizing, required inductor quality factors or minimum supply voltage. The model considers limitations that CMOS processes can impose on implementation. The book also provides diffe

  20. Systematic Approach for Design of Broadband, High Efficiency, High Power RF Amplifiers

    National Research Council Canada - National Science Library

    Mohadeskasaei, Seyed Alireza; An, Jianwei; Chen, Yueyun; Li, Zhi; Abdullahi, Sani Umar; Sun, Tie

    2017-01-01

    ...‐AB RF amplifiers with high gain flatness. It is usually difficult to simultaneously achieve a high gain flatness and high efficiency in a broadband RF power amplifier, especially in a high power design...

  1. Effect of absorbed pump power on the quality of output beam from monolithic microchip lasers

    Indian Academy of Sciences (India)

    Pranab K Mukhopadhyay; K Ranganathan; Jogy George; S K Sharma; T P S Nathan

    2002-04-01

    The dependence of the beam propagation factor (2 parameter) with the absorbed pump power in the case of monolithic microchip laser under face-cooled configuration is extensively studied. Our investigations show that the 2 parameter is related to the absorbed pump power through two parameters ( and ) whose values depend on the laser material properties and laser configuration. We have shown that one parameter arises due to the oscillation of higher order modes in the microchip cavity and the other parameter accounts for the spherical aberration associated with the thermal lens induced by the pump beam. Such dependency of 2 parameter with the absorbed pump power is experimentally verified for a face-cooled monolithic microchip laser based on Nd3+ - doped GdVO4 crystal and the values of and parameters were estimated from the experimentally measured data points.

  2. 5.2 GHz variable-gain amplifier and power amplifier driver for WLAN IEEE 802.11a transmitter front-end

    Institute of Scientific and Technical Information of China (English)

    Zhang Xuelian; Yan Jun; Shi Yin; Dai Fa Foster

    2009-01-01

    A 5.2 GHz variable-gain amplifier (VGA) and a power amplifier (PA) driver are designed for WLAN IEEE 802.11a monolithic RFIC. The VGA and the PA driver are implemented in a 50 GHz 0.35 μm SiGe BiCMOS technology and occupy 1.12×1.25 mm2 die area. The VGA with effective temperature compensation is controlled by 5 bits and has a gain range of 34 dB. The PA driver with tuned loads utilizes a differential input, single-ended output topology, and the tuned loads resonate at 5.2 GHz. The maximum overall gain of the VGA and the PA driver is 29 dB with the output third-order intercept point (OIP3) of 11 dBm. The gain drift over the temperature varying from -30 to 85℃ converges within±3 dB. The total current consumption is 45 mA under a 2.85 V power supply.

  3. Digitally Controlled Envelope Tracking Power Supply for an RF Power Amplifier

    DEFF Research Database (Denmark)

    Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.

    2007-01-01

    due to clock frequency quantization. An envelope tracking power supply for an RF Power Amplifier (RFPA) can help improve system efficiency by reducing the power consumption of the RFPA. To show the advantage of the DiSOM over traditional counter based Digital PWM modulators two designs were compared...

  4. TEDS Base Station Power Amplifier using Low-Noise Envelope Tracking Power Supply

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.

    2009-01-01

    This paper demonstrates a highly linear and efficient TETRA enhanced data service (TEDS) base-station RF power amplifier (RFPA). Based on the well-known combination of an envelope tracking (ET) power supply and a linear class-A/B RFPA, adequate adjacent channel power ratio (ACPR) and wideband noise...

  5. VDMOS transistors for power amplifier in UHF band

    Science.gov (United States)

    Kassmi, Kamal

    Modeling of power VDMOSFET transistors working in the UHF band is considered. VDMOSFET power structures suited to mobile radiotelephony power amplification are described. A nonlinear physical model suitable for all working regimes is developed. The elements of this model only depend on physical and technological data and bias voltages of the device. A reduced model compatible with SPICE (Simulation Program with Integrated Circuit Emphasis) is presented. A first comparison between measured and computed characteristics is presented under DC switching and small signal conditions. A methodology for the study and design of radio frequency power amplifiers in a nonlinear regime is described. The performance of these devices in terms of power gain, output power, efficiency, linearity and the drain bias influence as well as third order Intermodulation Distortion (IMD3) are considered. It is shown that IMD and power gain performances are controlled by DC output characteristics in the ohmic zone. Practical conclusions with respect to the intrinsic qualities and drawbacks of these products for UHF power amplification are drawn.

  6. Thermal effects in high average power optical parametric amplifiers.

    Science.gov (United States)

    Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas

    2013-03-01

    Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given.

  7. X-Parameter Based Modelling of Polar Modulated Power Amplifiers

    DEFF Research Database (Denmark)

    Wang, Yelin; Nielsen, Troels Studsgaard; Sira, Daniel

    2013-01-01

    X-parameters are developed as an extension of S-parameters capable of modelling non-linear devices driven by large signals. They are suitable for devices having only radio frequency (RF) and DC ports. In a polar power amplifier (PA), phase and envelope of the input modulated signal are applied...... at separate ports and the envelope port is neither an RF nor a DC port. As a result, X-parameters may fail to characterise the effect of the envelope port excitation and consequently the polar PA. This study introduces a solution to the problem for a commercial polar PA. In this solution, the RF-phase path...

  8. Development of copper bromide laser master oscillator power amplifier system

    Indian Academy of Sciences (India)

    G N Tiwari; R K Mishra; R Khare; S V Nakhe

    2014-02-01

    Development of master oscillator power amplifier (MOPA) system of copper bromide laser (CBL) operating at 110 W average power is reported. The spectral distribution of power at green (510.6 nm) and yellow (578.2 nm) components in the output of a copper bromide laser is studied as a function of operating parameters. The electrical input power was varied from 2.6 to 4.3 kW, the pulse repetition frequency (PRF) was changed from 16 to 19 kHz, and the pressure of the buffer gas (neon) was kept fixed at 20 mbar. When the electrical input power was increased to 4.3 kW from 2.6 kW, the tube-wall temperature also increased to 488°C from 426°C but the ratio of the green to yellow power decreased to 1.53 from 3.73. The ratio of green to yellow power decreased to 1.53 from 1.63 when the PRF of the laser was increased to 19 kHz from 16 kHz. These observations are explained in terms of electron temperature, energy levels of transitions, and voltage and current waveforms across the laser head.

  9. Design of mm-wave InP DHBT power amplifiers

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Yan, Lei

    2011-01-01

    power, gain, and efficiency. The design issues associated with cascode based power amplifiers at mm-wave frequencies is described. The experimental results on a two-way combined single-stage cascode based InP DHBT power amplifier demonstrate 13.4dB linear power gain and 12.5dBm saturated output power...

  10. Efficiency Enhancement of Pico-cell Base Station Power Amplifier MMIC in Gallium Nitride HFET Technology Using the Doherty technique

    Science.gov (United States)

    Seneviratne, Sashieka

    With the growth of smart phones, the demand for more broadband, data centric technologies are being driven higher. As mobile operators worldwide plan and deploy 4th generation (4G) networks such as LTE to support the relentless growth in mobile data demand, the need for strategically positioned pico-sized cellular base stations known as 'pico-cells' are gaining traction. In addition to having to design a transceiver in a much compact footprint, pico-cells must still face the technical challenges presented by the new 4G systems, such as reduced power consumptions and linear amplification of the signals. The RF power amplifier (PA) that amplifies the output signals of 4G pico-cell systems face challenges to minimize size, achieve high average efficiencies and broader bandwidths while maintaining linearity and operating at higher frequencies. 4G standards as LTE use non-constant envelope modulation techniques with high peak to average ratios. Power amplifiers implemented in such applications are forced to operate at a backed off region from saturation. Therefore, in order to reduce power consumption, a design of a high efficiency PA that can maintain the efficiency for a wider range of radio frequency signals is required. The primary focus of this thesis is to enhance the efficiency of a compact RF amplifier suitable for a 4G pico-cell base station. For this aim, an integrated two way Doherty amplifier design in a compact 10mm x 11.5mm2 monolithic microwave integrated circuit using GaN device technology is presented. Using non-linear GaN HFETs models, the design achieves high effi-ciencies of over 50% at both back-off and peak power regions without compromising on the stringent linearity requirements of 4G LTE standards. This demonstrates a 17% increase in power added efficiency at 6 dB back off from peak power compared to conventional Class AB amplifier performance. Performance optimization techniques to select between high efficiency and high linearity operation are

  11. Completely monolithic linearly polarized high-power fiber laser oscillator

    Science.gov (United States)

    Belke, Steffen; Becker, Frank; Neumann, Benjamin; Ruppik, Stefan; Hefter, Ulrich

    2014-03-01

    We have demonstrated a linearly polarized cw all-in-fiber oscillator providing 1 kW of output power and a polarization extinction ratio (PER) of up to 21.7 dB. The design of the laser oscillator is simple and consists of an Ytterbium-doped polarization maintaining large mode area (PLMA) fiber and suitable fiber Bragg gratings (FBG) in matching PLMA fibers. The oscillator has nearly diffraction-limited beam quality (M² high power 6+1:1 pump coupler. The slope efficiency of the laser is 75 %. The electro/optical efficiency of the complete laser system is ~30 % and hence in the range of Rofin's cw non-polarized fiber lasers. Choosing an adequate bending diameter for the Yb-doped PLMA fiber, one polarization mode as well as higher order modes are sufficiently supressed1. Resulting in a compact and robust linearly polarized high power single mode laser without external polarizing components. Linearly polarized lasers are well established for one dimensional cutting or welding applications. Using beam shaping optics radially polarized laser light can be generated to be independent from the angle of incident to the processing surface. Furthermore, high power linearly polarized laser light is fundamental for nonlinear frequency conversion of nonlinear materials.

  12. High Power Narrow Linewidth 1.26 Micron Ho-Doped Fiber Amplifier Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is for the development of an innovative, high power, and extremely reliable 1.26-micron Ho-doped fluoride fiber amplifier. The proposed fiber amplifier...

  13. High Power Narrow Linewidth 1.26 Micron Ho-Doped Fiber Amplifier Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is for the development of an innovative, high power, and extremely reliable 1.26-micron Ho-doped fluoride fiber amplifier. The proposed fiber amplifier...

  14. Theoretical analysis of quantum dot amplifiers with high saturation power and low noise figure

    DEFF Research Database (Denmark)

    Berg, Tommy Winther; Mørk, Jesper

    2002-01-01

    Semiconductor quantum dot amplifiers are predicted to exhibit superior characteristics such as high gain, and output power and low noise. The analysis provides criteria and design guidelines for the realization of high quality amplifiers.......Semiconductor quantum dot amplifiers are predicted to exhibit superior characteristics such as high gain, and output power and low noise. The analysis provides criteria and design guidelines for the realization of high quality amplifiers....

  15. Time-reversal duality of high-efficiency RF power amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Reveyrand, T; Ramos, I; Popovic, Z

    2012-12-06

    The similarity between RF power amplifiers and rectifiers is discussed. It is shown that the same high-efficiency harmonically-terminated power amplifier can be operated in a dual rectifier mode. Nonlinear simulations with a GaN HEMT transistor model show the time-reversal intrinsic voltage and current waveform relationship between a class-F amplifier and rectifier. Measurements on a class-F-1 amplifier and rectifier at 2.14 GHz demonstrate over 80% efficiency in both cases.

  16. Multi-pass amplifier architecture for high power laser systems

    Science.gov (United States)

    Manes, Kenneth R; Spaeth, Mary L; Erlandson, Alvin C

    2014-04-01

    A main amplifier system includes a first reflector operable to receive input light through a first aperture and direct the input light along an optical path. The input light is characterized by a first polarization. The main amplifier system also includes a first polarizer operable to reflect light characterized by the first polarization state. The main amplifier system further includes a first and second set of amplifier modules. Each of the first and second set of amplifier modules includes an entrance window, a quarter wave plate, a plurality of amplifier slablets arrayed substantially parallel to each other, and an exit window. The main amplifier system additionally includes a set of mirrors operable to reflect light exiting the first set of amplifier modules to enter the second set of amplifier modules and a second polarizer operable to reflect light characterized by a second polarization state.

  17. RF power amplifier: pushing the boundaries of performance versus cost

    Science.gov (United States)

    De Souza, M. M.; Chevaux, N.; Rasheduzzaman, M.

    2012-10-01

    The Radio Frequency Power Amplifier lies at the heart of all modern day communication systems ranging from the cellular infrastructure market to broadcast, radar, medical, automotive and military to name a few. Transmission systems not only require substantial power at high frequencies, but they are also one of the most demanding of semiconductor applications on account of their requirements for efficiency and linearity, which inherently introduces a tradeoff during design. Three types of device technologies have been in typical use for RF power amplification: the VDMOS (at frequencies upto 1 GHz), the LDMOS (at frequencies upto 3.5 GHz), and more recently the Gallium Nitride HEMT, which extends the frequency range upto 5-7 GHz. As an emerging technology, GaN has huge potential, but its widespread use is still currently limited by the level of experience, absence of reliable device models and prices which are roughly (6-10 times that of silicon). This overview highlights the distinct features of the RF Power devices and touches upon the performance metrics of the above technologies (in silicon and GaN).

  18. Direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    This paper discusses the advantages and problems when implementing direct energy conversion switching-mode audio power amplifiers. It is shown that the total integration of the power supply and Class D audio power amplifier into one compact direct converter can simplify the design, increase...... efficiency, reduce the product volume and lower its cost. As an example, the principle of operation and the measurements made on a direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp are presented....

  19. SiGe HBTs Optimization for Wireless Power Amplifier Applications

    Directory of Open Access Journals (Sweden)

    Pierre-Marie Mans

    2010-01-01

    Full Text Available This paper deals with SiGe HBTs optimization for power amplifier applications dedicated to wireless communications. In this work, we investigate the fT-BVCEO tradeoff by various collector optimization schemes such as epilayer thickness and dopant concentration, and SIC and CAP characteristics. Furthermore, a new trapezoidal base Germanium (Ge profile is proposed. Thanks to this profile, precise control of Ge content at the metallurgical emitter-base junction is obtained. Gain stability is obtained for a wide range of temperatures through tuning the emitter-base junction Ge percent. Finally, a comprehensive investigation of Ge introduction into the collector (backside Ge profile is conducted in order to improve the fT values at high injection levels.

  20. Cascade Structure of Digital Predistorter for Power Amplifier Linearization

    Directory of Open Access Journals (Sweden)

    E. B. Solovyeva

    2015-12-01

    Full Text Available In this paper, a cascade structure of nonlinear digital predistorter (DPD synthesized by the direct learning adaptive algorithm is represented. DPD is used for linearization of power amplifier (PA characteristic, namely for compensation of PA nonlinear distortion. Blocks of the cascade DPD are described by different models: the functional link artificial neural network (FLANN, the polynomial perceptron network (PPN and the radially pruned Volterra model (RPVM. At synthesis of the cascade DPD there is possibility to overcome the ill conditionality problem due to reducing the dimension of DPD nonlinear operator approximation. Results of compensating nonlinear distortion in Wiener–Hammerstein model of PA at the GSM–signal with four carriers are shown. The highest accuracy of PA linearization is produced by the cascade DPD containing PPN and RPVM.

  1. 2.5 GHz integrated graphene RF power amplifier on SiC substrate

    Science.gov (United States)

    Hanna, T.; Deltimple, N.; Khenissa, M. S.; Pallecchi, E.; Happy, H.; Frégonèse, S.

    2017-01-01

    In this work, we report the design of 2.5 GHz integrated power amplifier based on a graphene FET fabricated with thermal deposition on SiC. In this first large signal study of graphene radiofrequency power amplifiers, a power gain of 8.9 dB is achieved, the maximum reported output power and power added efficiency are 5.1 dBm and 2.2% respectively. Furthermore, graphene and Si CMOS amplifiers are compared; conclusions are drawn towards the technology enhancements to optimize the amplifiers figures of merit.

  2. Self-oscillating modulators for direct energy conversion audio power amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.; Andersen, Michael A.E.

    2005-07-01

    Direct energy conversion audio power amplifier represents total integration of switching-mode power supply and Class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count and eventually low cost. This paper presents how self-oscillating modulators can be used with the direct switching-mode audio power amplifier to improve its performance by providing fast hysteretic control with high power supply rejection ratio, open-loop stability and high bandwidth. Its operation is thoroughly analyzed and simulated waveforms of a prototype amplifier are presented. (au)

  3. Self-oscillating modulators for direct energy conversion audio power amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.; Andersen, Michael A.E.

    2005-07-01

    Direct energy conversion audio power amplifier represents total integration of switching-mode power supply and Class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count and eventually low cost. This paper presents how self-oscillating modulators can be used with the direct switching-mode audio power amplifier to improve its performance by providing fast hysteretic control with high power supply rejection ratio, open-loop stability and high bandwidth. Its operation is thoroughly analyzed and simulated waveforms of a prototype amplifier are presented. (au)

  4. Self-oscillating modulators for direct energy conversion audio power amplifiers

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2005-01-01

    Direct energy conversion audio power amplifier represents total integration of switching-mode power supply and Class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count and eventually low cost. This paper presents how self......-oscillating modulators can be used with the direct switching-mode audio power amplifier to improve its performance by providing fast hysteretic control with high power supply rejection ratio, open-loop stability and high bandwidth. Its operation is thoroughly analyzed and experimental results from prototype amplifier...

  5. A high-linearity InGaP/GaAs HBT power amplifier for IEEE 802.11a/n

    Institute of Scientific and Technical Information of China (English)

    Cui Jie; Chen Lei; Kang Chunlei; Shi Jia; Zhang Xuguang; Ai Baoli; Liu Yi

    2013-01-01

    A three-stage 4.8-6 GHz monolithic power amplifier (PA) compatible with IEEE 802.11 a/n designed based on an advanced 2 μm InGaP/GaAs hetero-junction bipolar transistor (HBT) process is presented.The PA integrates input matching and closed-loop power control circuits on chip.Under 3.3 V DC bias,the amplifier achieves a ~31 dB small signal gain,excellent wide band input and output matching among overall 1.2 GHz bandwidth,and up to 24.5 dBm linear output power below EVM 3% with IEEE 802.1 la 64QAM OFDM input signal.

  6. 338-GHz Semiconductor Amplifier Module

    Science.gov (United States)

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

    2010-01-01

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

  7. 75 FR 3985 - Trade Regulation Rule Relating to Power Output Claims for Amplifiers Utilized in Home...

    Science.gov (United States)

    2010-01-26

    ... receive information useful to their purchasing decision, or, at worst, could be deceived by certain power... CFR Part 432 Trade Regulation Rule Relating to Power Output Claims for Amplifiers Utilized in Home... Rule Relating to Power Output Claims for Amplifiers Utilized in Home Entertainment Products...

  8. High Efficiency, High Linearity, Switch Mode Power Amplifiers for Varying envelop Signal Applications

    DEFF Research Database (Denmark)

    Tong, Tian; Sira, Daniel; Nielsen, Michael;

    2009-01-01

    using switch-mode power amplifier aided by various linearization techniques can present a feasible way to achieve both high linearity and high power efficiency. In this paper two different implementations of the switch-mode power amplifier a re p resented for varying envelop applications: the RF pulse...

  9. Monolithic solid oxide fuel cell technology advancement for coal-based power generation

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-14

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  10. Linearization and efficiency enhancement of power amplifiers using digital predistortion

    Energy Technology Data Exchange (ETDEWEB)

    Safari, Nima

    2008-07-01

    Today, demand of higher spectral efficiency forces wireless communication systems to employ non-constant envelope modulation schemes such as Quadrature Amplitude Modulations (QAM), Code Division Multiple Access (CDMA) and Orthogonal Frequency-Division Multiplexing (OFDM) schemes. These modulation techniques generate signals with wide range of envelope fluctuation. This property makes these schemes sensitive to nonlinear amplifications. Nonlinearities introduced by Power Amplifiers (PA) cause both a distortion of the signal and an increased out of band output spectrum, which leads to a rise in adjacent channel interference. Thus, in order to ensure a high spectral efficiency and to avoid spectral regrowth, a linearization technique is required. Among all the linearization techniques, basedband Digital Predistortion (DPD) is one of the commonly used linearization techniques, which is characterized by robust operation, low implementation cost and high accuracy. In the first chapter of this thesis, an introduction on the motivation and necessity of using PA linearization techniques is presented. Digital Predistortion as a popular linearization technique aims to improve the efficiency and linearity of RF power amplifiers. The scope of the thesis, the goals to be achieved and the contributions are also discussed in chapter one. Chapter two, mainly discusses sample-by-sample updating algorithm in Digital Predistorters to adaptively linearize the PA memoryless nonlinearities. Look-up Table (LUT) and polynomial approaches are studied and implemented in Hardware using a test-bed provided by Nera Research. The experimental results together with a discussion are then given. A new DPD algorithm based on block estimation is proposed in chapter three to avoid realtime signal processing, reduce the complexity and also avoid the bad performance during the slow adaptation of adaptive the Adjacent Channel Power Ratio (ACPR) and the Error Vector Magnitude (EVM) requirements. In

  11. Power scaling of supercontinuum seeded megahertz-repetition rate optical parametric chirped pulse amplifiers.

    Science.gov (United States)

    Riedel, R; Stephanides, A; Prandolini, M J; Gronloh, B; Jungbluth, B; Mans, T; Tavella, F

    2014-03-15

    Optical parametric chirped-pulse amplifiers with high average power are possible with novel high-power Yb:YAG amplifiers with kW-level output powers. We demonstrate a compact wavelength-tunable sub-30-fs amplifier with 11.4 W average power with 20.7% pump-to-signal conversion efficiency. For parametric amplification, a beta-barium borate crystal is pumped by a 140 W, 1 ps Yb:YAG InnoSlab amplifier at 3.25 MHz repetition rate. The broadband seed is generated via supercontinuum generation in a YAG crystal.

  12. A monolithic integrated low-voltage deep brain stimulator with wireless power and data transmission

    Science.gov (United States)

    Zhang, Zhang; Ye, Tan; Jianmin, Zeng; Xu, Han; Xin, Cheng; Guangjun, Xie

    2016-09-01

    A monolithic integrated low-voltage deep brain stimulator with wireless power and data transmission is presented. Data and power are transmitted to the stimulator by mutual inductance coupling, while the in-vitro controller encodes the stimulation parameters. The stimulator integrates the digital control module and can generate the bipolar current with equal amplitude in four channels. In order to reduce power consumption, a novel controlled threshold voltage cancellation rectifier is proposed in this paper to provide the supply voltage of the stimulator. The monolithic stimulator was fabricated in a SMIC 0.18 μm 1-poly 6-metal mixed-signal CMOS process, occupying 0.23 mm2, and consumes 180 μW on average. Compared with previously published stimulators, this design has advantages of large stimulated current (0-0.8 mA) with the double low-voltage supply (1.8 and 3.3 V), and high-level integration. Project supported by the National Natural Science Foundation of China (Nos. 61404043, 61401137), the Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences (Nos. IIMDKFJJ-13-06, IIMDKFJJ-14-03), and the Fundamental Research Funds for the Central Universities (No. 2015HGZX0026).

  13. Efficient regenerative wavelength conversion at 10Gbit/s over C- and L-band (80nm span) using a Mach-Zehnder interferometer with monolithically integrated semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Dülk, M.; Fischer, St.; Gamper, E.;

    2000-01-01

    A demonstration is presented of 10Gbit/s 2R regenerative wavelength up- and down-conversion within the C-band as well as up-conversion to the L-band using a monolithically integrated Mach-Zehnder interferometer module with semiconductor optical amplifiers (MZI-SOAs). The converted output signals ...

  14. A Q-band low noise GaAs pHEMT MMIC power amplifier for pulse electron spin resonance spectrometer

    Science.gov (United States)

    Sitnikov, A.; Kalabukhova, E.; Oliynyk, V.; Kolisnichenko, M.

    2017-05-01

    We present the design and development of a single stage pulse power amplifier working in the frequency range 32-38 GHz based on a monolithic microwave integrated circuit (MMIC). We have designed the MMIC power amplifier by using the commercially available packaged GaAs pseudomorphic high electron mobility transistor. The circuit fabrication and assembly process includes the elaboration of the matching networks for the MMIC power amplifier and their assembling as well as the topology outline and fabrication of the printed circuit board of the waveguide-microstrip line transitions. At room ambient temperature, the measured peak output power from the prototype amplifier is 35.5 dBm for 16.6 dBm input driving power, corresponding to 19 dB gain. The measured rise/fall time of the output microwave signal modulated by a high-speed PIN diode was obtained as 5-6 ns at 20-250 ns pulse width with 100 kHz pulse repetition rate frequency.

  15. NONLINEAR CHARACTERIZATION OF CONCURRENT DUAL-BAND RF POWER AMPLIFIERS

    Institute of Scientific and Technical Information of China (English)

    Hui Ming; Liu Taijun; Ye Yan; Zhang Haili; Shen Dongya; Li Liang

    2012-01-01

    In this paper,the synchronous concurrent dual-band RF signal is used to drive the RF Power Amplifier (PA).The nonlinear characterization of a concurrent dual-band RF PA is discussed while two band signals in the dual-band are modulated by CDMA2000 and WCDMA signals.When the two band signals in the dual-band of the PA are modulated with the same signals,it is found that the nonlinearity of the PA can be expressed by any of the two corresponding baseband data.On the other hand,when the two band signals in the dual-band of the PA are modulated with two different signals,the PA nonlinearity cannot be characterized by any of the two corresponding baseband data.In this case,its nonlinearity has to be denoted by a composite signals consisting of the two baseband signals.Consequently,the requirements for the speed of the A/D converter can be largely reduced.The experimental results with CDMA2000 and WCDMA signals demonstrate the speed of the A/D converter required is only 30 M Sample Per Second (SaPS),but it will be at least 70 M SaPS for the conventional method.

  16. On the power amplifier nonlinearity in MIMO transmit beamforming systems

    KAUST Repository

    Qi, Jian

    2012-03-01

    In this paper, single-carrier multiple-input multiple-output (MIMO) transmit beamforming (TB) systems in the presence of high-power amplifier (HPA) nonlinearity are investigated. Specifically, due to the suboptimality of the conventional maximal ratio transmission/maximal ratio combining (MRT/MRC) under HPA nonlinearity, we propose the optimal TB scheme with the optimal beamforming weight vector and combining vector, for MIMO systems with nonlinear HPAs. Moreover, an alternative suboptimal but much simpler TB scheme, namely, quantized equal gain transmission (QEGT), is proposed. The latter profits from the property that the elements of the beamforming weight vector have the same constant modulus. The performance of the proposed optimal TB scheme and QEGT/MRC technique in the presence of the HPA nonlinearity is evaluated in terms of the average symbol error probability and mutual information with the Gaussian input, considering the transmission over uncorrelated quasi-static frequency-flat Rayleigh fading channels. Numerical results are provided and show the effects on the performance of several system parameters, namely, the HPA parameters, numbers of antennas, quadrature amplitude modulation modulation order, number of pilot symbols, and cardinality of the beamforming weight vector codebook for QEGT. © 2012 IEEE.

  17. A C-band GaN based linear power amplifier with 55.7% PAE

    Science.gov (United States)

    Luo, Weijun; Chen, Xiaojuan; Zhang, Hui; Liu, Guoguo; Zheng, Yingkui; Liu, Xinyu

    2010-04-01

    A C-band linear power amplifier is successfully developed with a one-chip 2 mm AlGaN/GaN high electron mobility transistors (HEMTs). Two kinds of matching circuits for the linear power amplifier are compared. Besides, stabilization methods for the amplifier are also discussed. At 5.4 GHz, the developed GaN HEMTs linear power amplifier delivers a 37.2 dBm (5.2 W) cw P1 dB output power with 9 dB linear gain and 55.7% maximum power-added efficiency (PAE) with a drain voltage of 25 V. To our best knowledge, the achieved PAE is the state-of-the-art result ever reported for 2 mm gate width single die GaN-based hybrid microwave integrated power amplifier at C-band.

  18. A 24 channel acoustic/vibration test power amplifier

    Science.gov (United States)

    Barlett, F. R.

    1978-01-01

    In the present paper, the advantages and drawbacks of a multichannel amplifier operating in a vibration or acoustic facility are discussed. The configuration of the facility and the multichannel amplifier proposed is a compromise based on the particular requirements and anticipated work load in a specific case under consideration.

  19. An RF-input outphasing power amplifier with RF signal decomposition network

    OpenAIRE

    Barton, Taylor W.; Perreault, David J.

    2015-01-01

    This work presents an outphasing power amplifier that directly amplifies a modulated RF input. The approach eliminates the need for multiple costly IQ modulators and baseband signal component separation found in conventional outphasing power amplifier systems, which have previously required both an RF carrier input and a separate baseband input to synthesize a modulated RF output. A novel RF signal decomposition network enables direct RF-input / RF-output outphasing by directly synthesizing t...

  20. Power amplifier for 1064 nm using Yb3+-doped double-clad fiber

    Institute of Scientific and Technical Information of China (English)

    Lingfeng Kong(孔令峰); Qihong Lou(楼祺洪); Jun Zhou(周军); Zhonglin Wu(吴中林); Jingxing Dong(董景星); Yunrong Wei(魏运荣); Jianqiang Zhu(朱健强)

    2004-01-01

    @@ A master-oscillator fiber power amplifier(MOPA)system is presented,which consists of a single modelaser as the master oscillator and an Yba+-doped large-mode-area double-clad fiber as the power amplifier.The system emits up to 6 W of amplified radiation at a wavelength of 1064 nm.The slope efficiency andextracted pulse energy as a function of pulse repetition rate are analyzed.

  1. Low-power, enhanced-gain adaptive-biasing-based Operational Transconductance Amplifiers

    DEFF Research Database (Denmark)

    Moradi, Farshad

    A symmetrical PMOS OTA (Operational Transconductance Amplifier) is used to build an advanced rail-to-rail amplifier with improved DC-gain and reduced power consumption. By using the adaptive biasing circuit for two differential inputs, a low stand-by current can be achieved, reducing power...

  2. L-band AlGaN/GaN Power Amplifier with Protection Against Load Mismatch

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Houwen, E.H. van der; Chowdhary, A.; Vliet, F.E. van

    2013-01-01

    Solid-state power amplifiers need protection at the output to handle high reflections due to mismatch. Normally this is implemented by using a ferrite-based isolator. These are however large and bulky components. This paper presents a Gallium-Nitride power amplifier module with automatic protection

  3. Stability investigation for InP DHBT mm‐wave power amplifier

    DEFF Research Database (Denmark)

    Yan, Lei; Johansen, Tom Keinicke; Kammersgaard, Jacob

    2013-01-01

    microwave integrated circuit power amplifier. Experimental results from a redesigned power amplifier with improved stability are presented to confirm that the previously detected oscillation loop is removed using odd‐mode stabilization resistors with the correct choice of values and locations. © 2012 Wiley...

  4. Design of Wireless Power Transfer System Using E-class Amplifier

    Science.gov (United States)

    Zhang, Le; Zhang, Yuan; Zhu, Wu; Huang, Jing

    2016-05-01

    This paper mainly discuss the wireless power transfer system based on class-E amplifier. Firstly, the system coupling model was established and the working principle and parameter design of class-E amplifier was analyzed in detail. Then proposed a method of high frequency driver design using high frequency power transistor push-pull mode. On this basis, we successfully designed and built the wireless power transfer system. The maximum transmission power is 15W and the transmission distance is 20cm. The method of class-E amplifier is verified in wireless power transfer system.

  5. Microwave dynamic large signal waveform characterization of advanced InGaP HBT for power amplifiers

    Institute of Scientific and Technical Information of China (English)

    Zhao Lixin; Jin Zhi; Liu Xinyu

    2009-01-01

    In wireless mobile communications and wireless local area networks (WLAN), advanced lnGaP HBT with power amplifiers are key components. In this paper, the microwave large signal dynamic waveform characteristics of an advanced InGaP HBT are investigated experimentally for 5.8 GHz power amplifier applications. The microwave large signal waveform distortions at various input power levels, especially at large signal level, are investigated and the reasons are analyzed. The output power saturation is also explained. These analyses will be useful for power amplifier designs.

  6. W-band Solid State Power Amplifier for Remote Sensing Radars Project

    Data.gov (United States)

    National Aeronautics and Space Administration — High power, compact, reliable and affordable power amplifiers operating in the W-band (94 GHz region) are critical to realizing transmitters for many NASA missions...

  7. MMIC for High-Efficiency Ka-BAnd GaN Power Amplifiers (2007043) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal addresses the need for high-efficiency, high-output power amplifiers operating in the Ka-band frequencies. For space communications, the power...

  8. 167 W, 1178 nm Ytterbium-Doped Photonic Bandgap Fiber Amplifier with Power Scalability

    DEFF Research Database (Denmark)

    Olausson, Christina Bjarnal Thulin; Shirakawa, Akira; Chen, Meishin

    2010-01-01

    We have generated 167 W of output power at 1178 nm using an ytterbium-doped photonic bandgap fiber. Distributed spectral filtering efficiently suppresses amplified spontaneous emission at shorter wavelengths and enables power scalable amplification at 1178nm.......We have generated 167 W of output power at 1178 nm using an ytterbium-doped photonic bandgap fiber. Distributed spectral filtering efficiently suppresses amplified spontaneous emission at shorter wavelengths and enables power scalable amplification at 1178nm....

  9. Diode-Pumped High Energy and High Average Power All-Solid-State Picosecond Amplifier Systems

    OpenAIRE

    Jiaxing Liu; Wei Wang; Zhaohua Wang; Zhiguo Lv; Zhiyuan Zhang; Zhiyi Wei

    2015-01-01

    We present our research on the high energy picosecond laser operating at a repetition rate of 1 kHz and the high average power picosecond laser running at 100 kHz based on bulk Nd-doped crystals. With diode-pumped solid state (DPSS) hybrid amplifiers consisting of a picosecond oscillator, a regenerative amplifier, end-pumped single-pass amplifiers, and a side-pumped amplifier, an output energy of 64.8 mJ at a repetition rate of 1 kHz was achieved. An average power of 37.5 W at a repetition ra...

  10. Empirical multichannel power consumption model for erbium-doped fiber amplifiers

    DEFF Research Database (Denmark)

    Saldaña Cercos, Silvia; de Paiva, Getulio E. R.; Argentato, Marcio Colazza;

    2015-01-01

    simultaneously contributes significantly, up to 48%, to the total power consumption due to the circuitry used for controlling the EDFA. As the number of simultaneous amplified WDM channels in high capacity long and medium reach transmission links reflects closely traffic patterns generated by end......In this paper we report on the first experimental power consumption analysis and model of single and multi-stage booster erbium-doped fiber amplifiers (EDFAs) with automatic gain control (AGC), accounting for channel number dependency. Results show that the amount of channels being amplified......-users, it is relevant to study channel number dependent power consumption for devising EDFA power efficient control and design....

  11. The Simulation Analysis of Nonlinear for a Power Amplifier with Memory Effects

    Directory of Open Access Journals (Sweden)

    Lv. Jinqiu

    2014-09-01

    Full Text Available For the nonlinear distortion problem of current power amplifiers (PAs with memory effects, we use goal programming to present a memoryless predistorter matrix model based on limiting baseband predistortion technique, and the normalized mean squared error (NMSE is limited in a satisfactory range while the output power is maximum. Then we propose a nonlinear power amplifier with memory effects based on back propagation neural network (BPNN with three tapped delay nodes and six single hidden layer nodes, which is single input - dual output. Simulation results show that the method proposed in this paper makes the experimental precision higher. Further, the linearization effect of power amplifiers becomes better.

  12. Direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.; Andersen, Michael A.E.

    2005-07-01

    This paper discusses the advantages and problems when implementing direct energy conversion switching-mode audio power amplifiers. It is shown that the total integration of the power supply and Class D audio power amplifier into one compact direct converter can simplify design, increase efficiency and integration level, reduce product volume and lower its cost. As an example, the principle of operation and the measurements made on a direct-conversion switching-mode audio power amplifier with active capacitive voltage clamp are presented. (au)

  13. Diode-Pumped High Energy and High Average Power All-Solid-State Picosecond Amplifier Systems

    Directory of Open Access Journals (Sweden)

    Jiaxing Liu

    2015-12-01

    Full Text Available We present our research on the high energy picosecond laser operating at a repetition rate of 1 kHz and the high average power picosecond laser running at 100 kHz based on bulk Nd-doped crystals. With diode-pumped solid state (DPSS hybrid amplifiers consisting of a picosecond oscillator, a regenerative amplifier, end-pumped single-pass amplifiers, and a side-pumped amplifier, an output energy of 64.8 mJ at a repetition rate of 1 kHz was achieved. An average power of 37.5 W at a repetition rate of 100 kHz pumped by continuous wave laser diodes was obtained. Compact, stable and high power DPSS laser amplifier systems with good beam qualities are excellent picosecond sources for high power optical parametric chirped pulse amplification (OPCPA and high-efficiency laser processing.

  14. A high efficiency C-band internally-matched harmonic tuning GaN power amplifier

    Science.gov (United States)

    Lu, Y.; Zhao, B. C.; Zheng, J. X.; Zhang, H. S.; Zheng, X. F.; Ma, X. H.; Hao, Y.; Ma, P. J.

    2016-09-01

    In this paper, a high efficiency C-band gallium nitride (GaN) internally-matched power amplifier (PA) is presented. This amplifier consists of 2-chips of self-developed GaN high-electron mobility transistors (HEMTs) with 16 mm total gate width on SiC substrate. New harmonic manipulation circuits are induced both in the input and output matching networks for high efficiency matching at fundamental and 2nd-harmonic frequency, respectively. The developed amplifier has achieved 72.1% power added efficiency (PAE) with 107.4 W output power at 5 GHz. To the best of our knowledge, this amplifier exhibits the highest PAE in C-band GaN HEMT amplifiers with over 100 W output power. Additionally, 1000 hours' aging test reveals high reliability for practical applications.

  15. A High-Efficiency Monolithic DC-DC PFM Boost Converter with Parallel Power MOS Technique

    Directory of Open Access Journals (Sweden)

    Hou-Ming Chen

    2013-01-01

    Full Text Available This paper presents a high-efficiency monolithic dc-dc PFM boost converter designed with a standard TSMC 3.3/5V 0.35 μm CMOS technology. The proposed boost converter combines the parallel power MOS technique with pulse-frequency modulation (PFM technique to achieve high efficiency over a wide load current range, extending battery life and reducing the cost for the portable systems. The proposed parallel power MOS controller and load current detector exactly determine the size of power MOS to increase power conversion efficiency in different loads. Postlayout simulation results of the designed circuit show that the power conversion is 74.9–90.7% efficiency over a load range from 1 mA to 420 mA with 1.5 V supply. Moreover, the proposed boost converter has a smaller area and lower cost than those of the existing boost converter circuits.

  16. A bit-rate flexible and power efficient all-optical demultiplexer realised by monolithically integrated Michelson interferometer

    DEFF Research Database (Denmark)

    Vaa, Michael; Mikkelsen, Benny; Jepsen, Kim Stokholm;

    1996-01-01

    A novel bit-rate flexible and very power efficient all-optical demultiplexer using differential optical control of a monolithically integrated Michelson interferometer with MQW SOAs is demonstrated at 40 to 10 Gbit/s. Gain switched DFB lasers provide ultra stable data and control signals....

  17. FPGA-Based Digital Current Switching Power Amplifiers Used in Magnetic Bearing Systems

    Science.gov (United States)

    Wang, Yin; Zhang, Kai; Dong, Jinping

    For a traditional two-level current switching power amplifier (PA) used in a magnetic bearing system, its current ripple is obvious. To increase its current ripple performance, three-level amplifiers are designed and their current control is generally based on analog and logical circuits. So the required hardware is complex and a performance increase from the hardware adjustment is difficult. To solve this problem, a FPGA-based digital current switching power amplifier (DCSPA) was designed. Its current ripple was obviously smaller than a two-level amplifier and its control circuit was much simpler than a tri-level amplifier with an analog control circuit. Because of the field-programmable capability of a FPGA chip used, different control algorithms including complex nonlinear algorithms could be easily implemented in the amplifier and their effects could be compared with the same hardware.

  18. Power neodymium-glass amplifier of a repetitively pulsed laser

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, Aleksandr V; Gaganov, V E; Garanin, Sergey G; Zhidkov, N V; Krotov, V A; Martynenko, S P; Pozdnyakov, E V; Solomatin, I I [Russian Federal Nuclear Center ' All-Russian Research Institute of Experimental Physics' , Sarov, Nizhnii Novgorod region (Russian Federation)

    2011-11-30

    A neodymium-glass diode-pumped amplifier with a zigzag laser beam propagation through the active medium was elaborated; the amplifier is intended for operation in a repetitively pulsed laser. An amplifier unit with an aperture of 20 Multiplication-Sign 25 mm and a {approx}40-cm long active medium was put to a test. The energy of pump radiation amounts to 140 J at a wavelength of 806 nm for a pump duration of 550 {mu}s. The energy parameters of the amplifier were experimentally determined: the small-signal gain per pass {approx}3.2, the linear gain {approx}0.031 cm{sup -1} with a nonuniformity of its distribution over the aperture within 15%, the stored energy of 0.16 - 0.21 J cm{sup -3}. The wavefront distortions in the zigzag laser-beam propagation through the active element of the amplifier did not exceed 0.4{lambda} ({lambda} = 0.63 {mu}m is the probing radiation wavelength).

  19. A novel design for monolithic interconnected modules (MIMs) for thermophotovoltaic (TPV) power conversion

    Energy Technology Data Exchange (ETDEWEB)

    Ward, J.S.; Duda, A.; Wanlass, M.W. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1997-06-01

    The design for the fabrication of Monolithic Interconnected Modules (MIMs) for thermophotovoltaic (TPV) power conversion described in this paper utilizes a novel, interdigitated contacting scheme that increases the flexibility in the size of the component cells and hence the output current and voltage of the module. This flexibility is gained at the expense of only minimally increased grid obscuration. Because the design uses the grid fingers of the component cells as the interconnect structure, the area of the device used for this purpose becomes negligible. In this paper the authors report on the specifics of the design as well as issues related to the fabrication of the modules. Preliminary performance data for representative modules also are offered.

  20. Peak power tunable mid-infrared oscillator pumped by a high power picosecond pulsed fiber amplifier with bunch output

    Science.gov (United States)

    Wei, Kaihua; Guo, Yan; Lai, Xiaomin; Fan, Shanhui

    2016-07-01

    A high power mid-infrared optical parametric oscillator (OPO) with picosecond pulse bunch output is experimentally demonstrated. The pump source was a high power master oscillation power amplifier (MOPA) picosecond pulsed fiber amplifier. The seed of the MOPA was a gain-switched distributed Bragg reflector (DBR) laser diode (LD) with picosecond pulse operation at a high repetition rate. The seed laser was amplified to 50 W by two-stage pre-amplifiers and a large mode area (LMA) Yb fiber based power-amplifier. A fiber-pigtailed acousto-optic modulator with the first order diffraction transmission was inserted into the second pre-amplifier to form a picosecond pulse bunch train and to change the peak power simultaneously. The power-amplified pulse bunches were focused to pump a wavelength-tunable OPO for emitting high power mid-infrared laser. By adjusting the OPO cavity length, the maximum average idler powers obtained at 3.1, 3.3 and 3.5 μm were 7, 6.6 and 6.4 W respectively.

  1. Comparison of Power Supply Pumping of Switch-Mode Audio Power Amplifiers with Resistive Loads and Loudspeakers as Loads

    DEFF Research Database (Denmark)

    Knott, Arnold; Petersen, Lars Press

    2013-01-01

    Power supply pumping is generated by switch-mode audio power amplifiers in half-bridge configuration, when they are driving energy back into their source. This leads in most designs to a rising rail voltage and can be destructive for either the decoupling capacitors, the rectifier diodes...... in the power supply or the power stage of the amplifier. Therefore precautions are taken by the amplifier and power supply designer to avoid those effects. Existing power supply pumping models are based on an ohmic load attached to the amplifier. This paper shows the analytical derivation of the resulting...... waveforms and extends the model to loudspeaker loads. Measurements verify, that the amount of supply pumping is reduced by a factor of 4 when comparing the nominal resistive load to a loudspeaker. A simplified and more accurate model is proposed and the influence of supply pumping on the audio performance...

  2. Short pulse mid-infrared amplifier for high average power

    CSIR Research Space (South Africa)

    Botha, LR

    2006-09-01

    Full Text Available @csir.co.za Telephone number of main author: +27-12-841-3447 Fax number of main author: +27-12-841-3152 Complete mailing address of main author: L R Botha, P O Box 395, Building 46, 2 nd Floor, Pretoria, 0001, South Africa Topic Area: Gas lasers including metal....1  Hz. If the relationship 4.0 vt is used then pulses as short as 0.5 ps can be amplified. The gain bandwidth can be increased by using isotopic mixtures and consequently this will allow pulses shorter than 0.5ps to be amplified. Gas lasers...

  3. Design of an S-band power combiner system with two parallel power amplifiers and phase shifters

    OpenAIRE

    Özbey, Burak

    2011-01-01

    Ankara : The Department of Electrical and Electronics Engineering and the Institute of Engineering and Science of Bilkent University, 2011. Thesis (Master's) -- Bilkent University, 2011. Includes bibliographical references leaves 70-72. RF power amplifiers are important blocks in a wireless communication system that play a vital role in determining the level of overall performance. In some situations, more power than a single power amplifier can alone provide is required in...

  4. X-band inverse class-F GaN internally-matched power amplifier

    Science.gov (United States)

    Zhao, Bo-Chao; Lu, Yang; Han, Wen-Zhe; Zheng, Jia-Xin; Zhang, Heng-Shuang; Ma, Pei-jun; Ma, Xiao-Hua; Hao, Yue

    2016-09-01

    An X-band inverse class-F power amplifier is realized by a 1-mm AlGaN/GaN high electron mobility transistor (HEMT). The intrinsic and parasitic components inside the transistor, especially output capacitor Cds, influence the harmonic impedance heavily at the X-band, so compensation design is used for meeting the harmonic condition of inverse class-F on the current source plane. Experiment results show that, in the continuous-wave mode, the power amplifier achieves 61.7% power added efficiency (PAE), which is 16.3% higher than the class-AB power amplifier realized by the same kind of HEMT. To the best of our knowledge, this is the first inverse class-F GaN internally-matched power amplifier, and the PAE is quite high at the X-band. Project supported by the National High Technology Research and Development Program of China (Grant No. 2015AA016801).

  5. High power pulse amplification of ytterbium-doped double-clad fiber amplifier

    Institute of Scientific and Technical Information of China (English)

    Liping Chang; Wei Fan; Jialin Chen; Li Wang; Bai Chen; Zunqi Lin

    2007-01-01

    By solving a set of time-dependent equations, the characteristics of the ytterbium-doped double-clad fiber amplifier are presented. Besides the steady state in the fiber of the upper-state population, pump power and amplified spontaneous emission without the input signal, the dynamic characteristics of the high power Gaussian pulse amplification like the evolution of pulse waveform distortion, upper-state population distribution and stored energy and pulse energy of the amplifier under the forward and backward pump,are simulated. The relations between the output pulse energy of the amplifier and the different input pulse peak power or pump power are also discussed. The models and results can provide important guide for the design and optimization of the high power pulse amplification.

  6. High-power microwave amplifier based on overcritical relativistic electron beam without external magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kurkin, S. A., E-mail: KurkinSA@gmail.com; Koronovskii, A. A. [Saratov State University, Astrakhanskaja 83, Saratov 410012 (Russian Federation); Saratov State Technical University, Politechnicheskaja 77, Saratov 410028 (Russian Federation); Frolov, N. S.; Hramov, A. E. [Saratov State Technical University, Politechnicheskaja 77, Saratov 410028 (Russian Federation); Saratov State University, Astrakhanskaja 83, Saratov 410012 (Russian Federation); Rak, A. O. [Belarusian State University of Informatics and Radioelectronics, Minsk (Belarus); Saratov State Technical University, Politechnicheskaja 77, Saratov 410028 (Russian Federation); Kuraev, A. A. [Belarusian State University of Informatics and Radioelectronics, Minsk (Belarus)

    2015-04-13

    The high-power scheme for the amplification of powerful microwave signals based on the overcritical electron beam with a virtual cathode (virtual cathode amplifier) has been proposed and investigated numerically. General output characteristics of the virtual cathode amplifier including the dependencies of the power gain on the input signal frequency and amplitude have been obtained and analyzed. The possibility of the geometrical working frequency tuning over the range about 8%–10% has been shown. The obtained results demonstrate that the proposed virtual cathode amplifier scheme may be considered as the perspective high-power microwave amplifier with gain up to 18 dB, and with the following important advantages: the absence of external magnetic field, the simplicity of construction, the possibility of geometrical frequency tuning, and the amplification of relatively powerful microwave signals.

  7. Impact of gain saturation on the mode instability threshold in high-power fiber amplifiers

    DEFF Research Database (Denmark)

    Hansen, Kristian Rymann; Lægsgaard, Jesper

    2014-01-01

    We present a coupled-mode model of transverse mode instability in high-power fiber amplifiers, which takes the effect of gain saturation into account. The model provides simple semi-analytical formulas for the mode instability threshold, which are valid also for highly saturated amplifiers...

  8. Small sized high-gain PHEMT high-power amplifiers for X-band applications

    NARCIS (Netherlands)

    Hek, A.P. de; Hunneman, P.A.H.

    2000-01-01

    The development of two small sized broadband X-band high-power amplifiers is discussed. The amplifiers are realised with the help of the pseudomorphic HEMT technology of the Fraunhofer Institute for Applied Solid State Physics (FhG-IAF). With the help of this technology the feasibility of

  9. High-Voltage class-D power amplifiers: design and optimization

    NARCIS (Netherlands)

    Ma, H.

    2015-01-01

    ABSTRACT Nowadays transducers are ubiquitous as interfaces between the increasingly digital world and the real physical world. The same holds for the power amplifiers driving them. This thesis focuses on the design and optimization of high-voltage class-D amplifiers, which are used for driving

  10. Ka-Band AlGaN/GaN HEMT high power and driver amplifier MMICs

    NARCIS (Netherlands)

    Heijningen, M. van; Vliet, F.E. van; Quay, R.; Raay, F. van; Kiefer, R.; Mueller, S.; Krausse, D.; Seelmann-Eggebert, M.; Mikulla, M.; Schlechtweg, M.

    2005-01-01

    In this paper the MMIC technology, design and characterization of a high power amplifier and driver amplifier MMIC at 30 GHz in AlGaN/GaN HEMT technology are presented. The MMICs are designed using CPW technology on a 390 μm thick SiC substrate. The measured small-signal gain of the driver is 14 dB

  11. A New Principle for a High Efficiency Power Audio Amplifier for Use with a Digital Preamplifier

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1986-01-01

    The use of class-B and class-D amlifiers for converting digital audio signals to analog signals is discussed. It is shown that the class-D amplifier is unsuitable due to distortion. Therefore, a new principle involving a switch-mode power supply and a class-B amplifier is suggested. By regulating...

  12. Small sized high-gain PHEMT high-power amplifiers for X-band applications

    NARCIS (Netherlands)

    Hek, A.P. de; Hunneman, P.A.H.

    2000-01-01

    The development of two small sized broadband X-band high-power amplifiers is discussed. The amplifiers are realised with the help of the pseudomorphic HEMT technology of the Fraunhofer Institute for Applied Solid State Physics (FhG-IAF). With the help of this technology the feasibility of integratin

  13. Output impedance and stability of audio power amplifiers

    NARCIS (Netherlands)

    Schaink, T.

    2006-01-01

    This report is about the design of an audio amplifier which is stable for all passive loads. If stability analysis of an opamp is done, the ‘classical’ approach is to derive its transfer function. Investigation of the open loop gain and a phase/gain margin determine the stability of the opamp. Desig

  14. An X-band four-way combined GaN solid-state power amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Chen Chi; Hao Yue; Feng Hui; Gu Wenping; Li Zhiming; Hu Shigang; Ma Teng, E-mail: ccachi@163.co [National Key Laboratory of Wide Band-Gap Semiconductor Technology, School of Microelectronics, Xidian University, Xi' an 710071 (China)

    2010-01-15

    An X-band four-way combined GaN solid-state power amplifier module is fabricated based on a self-developed AlGaN/GaN HEMT with 2.5-mm gate width technology on SiC substrate. The module consists of an AlGaN/GaN HEMT, Wilkinson power hybrids, a DC-bias circuit and microstrip matching circuits. For the stability of the amplifier module, special RC networks at the input and output, a resistor between the DC power supply and a transistor gate at the input and 3{lambda}/4 Wilkinson power hybrids are used for the cancellation of low frequency self-oscillation and crosstalk of each amplifier. Under V{sup ds} = 27 V, V{sup gs} = -4.0 V, CW operating conditions at 8 GHz, the amplifier module exhibits a line gain of 5 dB with a power added efficiency of 17.9%, and an output power of 42.93 dBm; the power gain compression is 2 dB. For a four-way combined solid-state amplifier, the power combining efficiency is 67.5%. It is concluded that the reduction in combining efficiency results from the non-identical GaN HMET, the loss of the hybrid coupler and the circuit fabricating errors of each one-way amplifier. (semiconductor integrated circuits)

  15. A compact high efficiency 8 kW 325 MHz power amplifier for accelerator applications

    Science.gov (United States)

    Mishra, Jitendra Kumar; Ramarao, B. V.; Pande, Manjiri M.; Singh, P.

    2014-11-01

    A solid state RF power amplifier (SSRFPA) has been designed and developed for 8 kW RF power at 325 MHz. The work was carried out to achieve high efficiency (over 70% efficiency), high gain and compact size for the amplifier module. The sub-components of this amplifier like a 1 kW amplifier module at 325 MHz, an 8-way RF power combiner rated for 8 kW RF power and a micro-strip based power divider have been designed and developed in-house. The size of the amplifier is miniaturized by incorporating innovative design techniques and proper selection of the substrate material in the input/output matching networks. Measured power gain and conversion efficiency of the solid state RF power amplifier module at 1.06 kW output is 21.7 dB and 73.2%, respectively. A coaxial line based 8-way Wilkinson power combiner has been designed and developed. Return loss of the combiner at the output (combined) port is 26.4 dB at 325 MHz. Transmission parameters of the combiner from each input (splitting) port to output port are 9.1 dB±0.15 dB. This amplifier uses a pre-driver of 20 W and a driver amplifier of 150 W. Total power gain and efficiency of 8 kW SSRFPA have been 92.3 dB (including the driver stages) and 68.3%, respectively. The harmonic content in the RF output is less than -50 dBc for all the harmonics. Main features of this development are high power density (kW/cm3), large value for kW/module, high efficiency (68.3%) for 8 kW SSRFPA at 325 MHz and rugged operation.

  16. A compact high efficiency 8 kW 325 MHz power amplifier for accelerator applications

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Jitendra Kumar, E-mail: jkmishra@barc.gov.in; Ramarao, B.V.; Pande, Manjiri M.; Singh, P.

    2014-11-11

    A solid state RF power amplifier (SSRFPA) has been designed and developed for 8 kW RF power at 325 MHz. The work was carried out to achieve high efficiency (over 70% efficiency), high gain and compact size for the amplifier module. The sub-components of this amplifier like a 1 kW amplifier module at 325 MHz, an 8-way RF power combiner rated for 8 kW RF power and a micro-strip based power divider have been designed and developed in-house. The size of the amplifier is miniaturized by incorporating innovative design techniques and proper selection of the substrate material in the input/output matching networks. Measured power gain and conversion efficiency of the solid state RF power amplifier module at 1.06 kW output is 21.7 dB and 73.2%, respectively. A coaxial line based 8-way Wilkinson power combiner has been designed and developed. Return loss of the combiner at the output (combined) port is 26.4 dB at 325 MHz. Transmission parameters of the combiner from each input (splitting) port to output port are 9.1 dB±0.15 dB. This amplifier uses a pre-driver of 20 W and a driver amplifier of 150 W. Total power gain and efficiency of 8 kW SSRFPA have been 92.3 dB (including the driver stages) and 68.3%, respectively. The harmonic content in the RF output is less than −50 dBc for all the harmonics. Main features of this development are high power density (kW/cm{sup 3}), large value for kW/module, high efficiency (68.3%) for 8 kW SSRFPA at 325 MHz and rugged operation.

  17. Low-timing-jitter high-power mode-locked 1063 nm Nd:GdVO₄ master oscillator power amplifier.

    Science.gov (United States)

    Wang, Zhi-min; Zhang, Feng-feng; Zuo, Jun-wei; Yang, Jing; Yuan, Lei; Peng, Qin-jun; Cui, Da-fu; Xu, Zu-yan

    2015-10-01

    A low-timing-jitter high-power semiconductor saturable absorber mirror mode-locked picosecond (ps) 1063 nm Nd:GdVO4 master oscillator power amplifier is presented. Using a single-pass Nd:GdVO4 amplifier, an amplified laser with 21.5 W output power and 8.3 ps pulsewidth was achieved at 250 MHz repetition rate. Employing a servo control, an average RMS timing jitter of ∼222  fs was realized. This laser can be used as a drive laser for photocathode injectors in free-electron lasers.

  18. A compact 500 MHz 4 kW Solid-State Power Amplifier for accelerator applications

    Science.gov (United States)

    Gaspar, M.; Pedrozzi, M.; Ferreira, L. F. R.; Garvey, T.

    2011-05-01

    We present the development of a compact narrow-band Solid-State Power Amplifier (SSPA). We foresee a promising application of solid-state amplifiers specifically in accelerators for new generation synchrotron light sources. Such a new technology has reached a competitive price/performance ratio and expected lifetime in comparison with klystron and IOT amplifiers. The increasing number of synchrotron light sources using 500 MHz as base frequency justifies the effort in the development of the proposed amplifier. Two different techniques are also proposed to improve the control and performance of these new distributed amplification systems which we call, respectively, complete distributed system and forced compression.

  19. Performance Analysis of Low Power, High Gain Operational Amplifier Using CMOS VLSI Design

    Directory of Open Access Journals (Sweden)

    Ankush S. Patharkar

    2014-07-01

    Full Text Available The operational amplifier is one of the most useful and important component of analog electronics. They are widely used in popular electronics. Their primary limitation is that they are not especially fast. The typical performance degrades rapidly for frequencies greater than about 1 MHz, although some models are designed specifically to handle higher frequencies. The primary use of op-amps in amplifier and related circuits is closely connected to the concept of negative feedback. The operational amplifier has high gain, high input impedance and low output impedance. Here the operational amplifier designed by using CMOS VLSI technology having low power consumption and high gain.

  20. A programmable log-linear amplifier for wide range nuclear power measuring channels

    Science.gov (United States)

    Khaleeq, M. Tahir; Alam, Mahmood; Ghumman, Iftikhar Ahmad

    2002-12-01

    A programmable log-linear amplifier has been developed for nuclear channels. The amplifier can be programmed for logarithmic, linear or log-linear mode of operation. In the log-linear mode, the amplifier operates partially in log mode and automatically switches to linear mode at any preset point. The log-linear mode is used for wide range operation of nuclear channels and, hence, the amplifier will improve the fault finding capabilities of the nuclear channels used in power range. The amplifier is tested at nuclear reactor and the results are found in very good agreement with the designed specifications. This article presents design and construction of the amplifier and field test results.

  1. Offering Students a Selection of Multiple Class B/AB Power Amplifiers as a Remote Laboratory

    National Research Council Canada - National Science Library

    Dag Andreas Hals Samuelsen; Olaf Hallan Graven

    2011-01-01

    In this paper a remote laboratory setup for conducting experiments on a class B/AB power amplifier is presented, addressing the problems related to running experiments requiring temperature matching...

  2. Optimized Pump Power Ratio on 2nd Order Pumping Discrete Raman Amplifier

    Institute of Scientific and Technical Information of China (English)

    Renxiang; Huang; Youichi; Akasaka; David; L.; Harris; James; Pan

    2003-01-01

    By optimizing pump power ratio between 1st order backward pump and 2nd order forward pump on discrete Raman amplifier, we demonstrated over 2dB noise figure improvement without excessive non-linearity degradation.

  3. High Performance Ka Band Power Amplifiers for Future EVA Radio Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this proposal, AlphaSense, Inc. and the University of Washington detail the development of a novel, high performance Ka band power amplifier for EVA radio...

  4. Heterojunction Bipolar Transistor Power Amplifiers for Long-Range X-band Communications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this SBIR Phase I project, Vega Wave Systems, Inc. will develop and demonstrate a novel InGaP-GaAs heterojunction bipolar transistor power amplifier for...

  5. Behavioral modeling of microwave power amplifiers using a look up table method

    NARCIS (Netherlands)

    Shen, Y.; Gajadharsing, J.; Tauritz, J.L.

    2007-01-01

    The possibility of building a microwave power amplifier (PA) behavioral model based on the look-up table principle is investigated. The model so constructed avoids the difficulties in model structure selection and/or its parameter estimation.

  6. High-average-power and high-beam-quality Innoslab picosecond laser amplifier.

    Science.gov (United States)

    Xu, Liu; Zhang, Hengli; Mao, Yefei; Yan, Ying; Fan, Zhongwei; Xin, Jianguo

    2012-09-20

    We demonstrated a laser-diode, end-pumped picosecond amplifier. With effective shaping of the seed laser, we achieved 73 W amplified laser output at the pump power of 255 W, and the optical-optical efficiency was about 28%. The beam propagation factors M(2) measured at the output power of 60 W in the horizontal direction and the vertical direction were 1.5 and 1.4, respectively.

  7. Gain and noise penalty for detuned 980 nm pumping or erbium-doped fiber power amplifiers

    DEFF Research Database (Denmark)

    Pedersen, B.; Chirravuri, J.; Miniscalco, W. J.

    1992-01-01

    The impact of altering the fiber length and pump wavelength on the gain and noise performance of erbium-doped fiber power amplifiers pumped in the 980-nm band is examined. A gain penalty of......The impact of altering the fiber length and pump wavelength on the gain and noise performance of erbium-doped fiber power amplifiers pumped in the 980-nm band is examined. A gain penalty of...

  8. A New Principle for a High Efficiency Power Audio Amplifier for Use with a Digital Preamplifier

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1986-01-01

    The use of class-B and class-D amlifiers for converting digital audio signals to analog signals is discussed. It is shown that the class-D amplifier is unsuitable due to distortion. Therefore, a new principle involving a switch-mode power supply and a class-B amplifier is suggested. By regulating...... the supply voltage to the amplifier according to the amplitude of the audio signal, a higher efficiency than can be obtained by the current principles is achieved. The regulation can be done very efficiently by generating the control signal to the power supply in advance of the audio signal, made possible...

  9. Power amplifiers for the S-, C-, X- and Ku-bands an EDA perspective

    CERN Document Server

    Božanić, Mladen

    2016-01-01

    This book provides a detailed review of power amplifiers, including classes and topologies rarely covered in books, and supplies sufficient information to allow the reader to design an entire amplifier system, and not just the power amplification stage. A central aim is to furnish readers with ideas on how to simplify the design process for a preferred power amplifier stage by introducing software-based routines in a programming language of their choice. The book is in two parts, the first focusing on power amplifier theory and the second on EDA concepts. Readers will gain enough knowledge of RF and microwave transmission theory, principles of active and passive device design and manufacturing, and power amplifier design concepts to allow them to quickly create their own programs, which will help to accelerate the transceiver design process. All circuit designers facing the challenge of designing an RF or microwave power amplifier for frequencies from 2 to 18 GHz will find this book to be a valuable asset.

  10. A describing function approach to bipolar RF-power amplifier simulation

    DEFF Research Database (Denmark)

    Vidkjær, Jens

    1981-01-01

    A method for fast and accurate computations of the primary performance parameters such as gain, efficiency, output power, and bandwidth in class-C biased RF-power amplifier stages is presented. The method is based on a describing function characterization of the RF-power transistor where the term...

  11. Output Impedance Shaping for Frequency Compensation of MOS Audio Power Amplifiers

    NARCIS (Netherlands)

    van der Zee, Ronan A.R.; Mostert, Fred

    2009-01-01

    A frequency compensation technique for MOS audio power amplifiers is presented that allows the frequency compensation capacitors around the power transistors to be smaller than the circuit parasitics without power or stability penalty. Stability is analysed by inspecting the output impedance of the

  12. CMOS 60-GHz and E-band power amplifiers and transmitters

    CERN Document Server

    Zhao, Dixian

    2015-01-01

    This book focuses on the development of design techniques and methodologies for 60-GHz and E-band power amplifiers and transmitters at device, circuit and layout levels. The authors show the recent development of millimeter-wave design techniques, especially of power amplifiers and transmitters, and presents novel design concepts, such as “power transistor layout” and “4-way parallel-series power combiner”, that can enhance the output power and efficiency of power amplifiers in a compact silicon area. Five state-of-the-art 60-GHz and E-band designs with measured results are demonstrated to prove the effectiveness of the design concepts and hands-on methodologies presented. This book serves as a valuable reference for circuit designers to develop millimeter-wave building blocks for future 5G applications.

  13. Self-Powered Ultrabroadband Photodetector Monolithically Integrated on a PMN-PT Ferroelectric Single Crystal.

    Science.gov (United States)

    Fang, Huajing; Xu, Chao; Ding, Jie; Li, Qiang; Sun, Jia-Lin; Dai, Ji-Yan; Ren, Tian-Ling; Yan, Qingfeng

    2016-12-07

    Photodetectors capable of detecting two or more bands simultaneously with a single system have attracted extensive attentions because of their critical applications in image sensing, communication, and so on. Here, we demonstrate a self-powered ultrabroadband photodetector monolithically integrated on a 0.72Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 (PMN-28PT) single crystal. By combining the optothermal and pyroelectric effect, the multifunctional PMN-28PT single crystal can response to a wide wavelength range from UV to terahertz (THz). At room temperature, the photodetector could generate a pyroelectric current under the intermittent illumination of incident light in absence of external bias. A systematic study of the photoresponse was investigated. The pyroelectric current shows an almost linear relationship to illumination intensity. Benefiting from the excellent pyroelectric property of PMN-28PT single crystal and the optimized device architecture, the device exhibited a dramatic improvement in operation frequency up to 3 kHz without any obvious degradation in sensitivity. Such a self-powered photodetector with ultrabroadband response may open a window for the novel application of ferroelectric materials in optoelectronics.

  14. Power scaling of a picosecond vortex laser based on a stressed Yb-doped fiber amplifier.

    Science.gov (United States)

    Koyama, Mio; Hirose, Tetsuya; Okida, Masahito; Miyamoto, Katsuhiko; Omatsu, Takashige

    2011-01-17

    Power scaling of a picosecond vortex laser based on a stressed Yb-doped fiber amplifier is analyzed. An output power of 25 W was obtained for 53 W of pumping, with a peak power of 37 kW. Frequency doubling of the vortex output was demonstrated using a nonlinear PPSLT crystal. A second-harmonic output power of up to 1.5 W was measured at a fundamental power of 11.2 W.

  15. Coherent Combining of High-Power Yb Fiber Amplifiers

    Science.gov (United States)

    2011-04-20

    the power~in-the-bucket ( PIB ) vertical beam quality (VBQ) [J 5], which is a related to the fraction of the power within a given far-field angle...compared with a reference ideal beam (the ideal tophat in this case). The power-in- the-bucket ( PIB ) vertical beam quality (VBQ) [I 5] is given by (c/ay!ll

  16. High-power near-diffraction-limited solid-state amplified spontaneous emission laser devices.

    Science.gov (United States)

    Smith, G; Shardlow, P C; Damzen, M J

    2007-07-01

    We present investigations into high-power scaling of solid-state amplified spontaneous emission (ASE) laser sources by use of two high-gain (~10(4)) Nd:YVO(4) bounce amplifiers. The sources deliver high power with a high-quality spatial output, but unlike a laser they have a high misalignment tolerance and do not require a precisely aligned cavity. In one system with two amplifiers, we demonstrate an ASE source with 24.5W of output power with good spatial quality, M(2)vertical. In a more sophisticated setup, the two amplifiers are arranged in a loop configuration producing 30W of ASE output with near-diffraction-limited spatial quality, with M(2)vertical, at an ~38% optical-to-optical conversion efficiency.

  17. The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier

    Energy Technology Data Exchange (ETDEWEB)

    J.G. Kulpin, K.J. Kleman, R.A. Legg

    2012-07-01

    A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

  18. Multi-Watt femtosecond optical parametric master oscillator power amplifier at 43 MHz.

    Science.gov (United States)

    Mörz, Florian; Steinle, Tobias; Steinmann, Andy; Giessen, Harald

    2015-09-07

    We present a high repetition rate mid-infrared optical parametric master oscillator power amplifier (MOPA) scheme, which is tunable from 1370 to 4120nm. Up to 4.3W average output power are generated at 1370nm, corresponding to a photon conversion efficiency of 78%. Bandwidths of 6 to 12nm with pulse durations between 250 and 400fs have been measured. Strong conversion saturation over the whole signal range is observed, resulting in excellent power stability. The system consists of a fiber-feedback optical parametric oscillator that seeds an optical parametric power amplifier. Both systems are pumped by the same Yb:KGW femtosecond oscillator.

  19. Nd:YVO4 amplifier for ultrafast low-power lasers.

    Science.gov (United States)

    Agnesi, Antonio; Carrà, Luca; Piccoli, Riccardo; Pirzio, Federico; Reali, Giancarlo

    2012-09-01

    An Nd:YVO4 amplifier consisting of two modules end pumped at 808 nm at 30 W total absorbed power has been designed for efficient, diffraction-limited amplification of ultrafast pulses from low-power seeders. We investigated amplification with a 50 mW, 7 ps Nd:YVO4 oscillator, a 2 mW, 15 ps Yb fiber laser, and a 30 mW, 300 fs Nd:glass laser. Output power as high as 9.5 W with 8 ps pulses was achieved with the 250 MHz vanadate seeder, whereas the 20 MHz fiber laser was amplified to 6 W. The femtosecond seeder allowed extracting Fourier-limited 4 ps pulses at 7 W output power. To our knowledge, these are the shortest pulses from any Nd:YVO4 laser device with at least 7 W output power. This suggests a novel approach to exploit the gain bandwidth of vanadate amplifiers with high output power levels. Such amplifier technology promises to offer an interesting alternative to high-power thin disk oscillators at few picoseconds duration, as well as to regenerative amplifiers with low-repetition-rate fiber seeders.

  20. Adaptive Digital Predistortion with Iterative Noise Cancelation for Power Amplifier Linearization

    Science.gov (United States)

    Jeon, Sungho; Kim, Junghyun; Lee, Jaekwon; Suh, Young-Woo; Seo, Jong-Soo

    In this paper, we propose a power amplifier linearization technique combined with iterative noise cancelation. This method alleviates the effect of added noises which prevents the predistorter (PD) from estimating the exact characteristics of the power amplifier (PA). To iteratively cancel the noise added in the feedback signal, the output signal of the power amplifier without noise is reconstructed by applying the inverse characteristics of the PD to the predistorted signals. The noise can be revealed by subtracting the reconstructed signals from the feedback signals. Simulation results based on the mean-square error (MSE) and power spectral density (PSD) criteria are presented to evaluate PD performance. The results show that the iterative noise cancelation significantly enhances the MSE performance, which leads to an improvement of the out-of-band power suppression. The performance of the proposed technique is verified by computer simulation and hardware test results.

  1. High efficiency class-Ⅰ audio power amplifier using a single adaptive supply

    Institute of Scientific and Technical Information of China (English)

    Peng Zhenfei; Yang Shanshan; Feng Yong; Liu Yang; Hong Zhiliang

    2012-01-01

    A high efficiency class-Ⅰ linear audio power amplifier (PA) with an adaptive supply is presented.Its efficiency is improved by a dynamic supply to reduce the power transistors' voltage drop.A gain compression technique is adopted to make the amplifier accommodate a single positive supply.Circuit complicity and chip area are reduced because no charge pump is necessary for the negative supply.A common shared mode voltage and a symmetric layout pattern are used to minimize the non-linearity.A peak efficiency of 80% is reached at peak output power.The measured THD+N before and after the supply switching point are 0.01% and 0.05%,respectively.The maximum output power is 410 mW for an 8 Ω speaker load.Unlike switching amplifiers,the class-Ⅰ amplifier operates as a linear amplifier and hence has a low EMI.The advantage of a high efficiency and low EMI makes the class-Ⅰ amplifier suitable for portable and RF sensitive applications.

  2. Theoretical treatment of modal instability in high-power cladding-pumped Raman amplifiers

    Science.gov (United States)

    Naderi, Shadi; Dajani, Iyad; Grosek, Jacob; Madden, Timothy

    2015-03-01

    Cladding-pumped Raman fiber amplifiers (RFA) have been proposed as gain media to achieve power scaling. It is well-known that the onset of the modal instability (MI) phenomenon is a limiting factor for achieving higher output powers in Yb-doped fiber amplifiers with good beam quality. In this paper, we present an analytical approach to the investigation of the MI phenomenon in high-power, cladding-pumped RFAs. By utilizing the conservation of the number of photons and the conservation of energy in the absence of loss, the nonlinear equations for the propagation of the pump power and the total signal power can be decoupled from one another. Decoupling lead to exact solutions for the pump power and transverse modes signal powers. Further we investigate various MI suppression techniques including increasing the seed power and gain-tailored design.

  3. High efficiency WCDMA power amplifier with Pulsed Load Modulation (PLM) technique

    Science.gov (United States)

    Liao, Shu-Hsien

    In wireless communication, high data rate complex modulation is used for spectral efficiency. However, power efficiency of power amplifier degrades when complex modulation is applied. Therefore, efficiency enhancement is necessary to maintain the performance. However, conventional efficiency enhancement schemes are nonlinear and performance improvement can only be optimized over a small range of power level. In order to preserve linearity and power efficiency, we propose a new digital power amplification technique "Pulsed Load Modulation (PLM)" for high efficiency and linear amplification. The PLM technique realizes load impedance modulation in digital fashion which is insensitive to device nonlinearity. Furthermore, the optimum power efficiency can be maintained over a wide range of output power. In this work, a PLM power amplifier module has been fabricated and to demonstrate the ability of PLM to provide high efficiency and linear amplification.

  4. Power Parameters and Efficiency of Class B Audio Amplifiers in Real-World Scenario

    Directory of Open Access Journals (Sweden)

    H. Zhivomirov

    2017-04-01

    Full Text Available Consumer audio amplifiers are intended to op¬erate with various loudspeaker loads, i.e. the load imped¬ance profile of the audio amplifier is a priori unknown. We propose the power parameters analysis of the class B audio amplifiers to be carried out in the realistic worst-case (RWC scenario of operation with the minimal value of the impedance and a RWC type of signal, instead of the nominal impedance of the loudspeaker and a sine-wave signal. Experimental validation, carried out for different types of signals and loudspeaker loads, demonstrate the advantages of the proposed RWC-based power parameters estimation. Furthermore, we provide a way of assessing the safe-operating area (SOA boundaries, based on the output I-V loci of the amplifier and by means of an equi¬valent load line (ELL.

  5. An Octave Bandwidth, High PAE, Linear, Class J GaN High Power Amplifier

    Science.gov (United States)

    2012-03-12

    versus the modeled small-signal gain and return loss response of the Class J amplifier using a 45-W CREE GaN HEMT . The amplifier has a gain of 13 to...AFFTC-PA-12055 An Octave Bandwidth, High PAE, Linear, Class J GaN High Power Amplifier Kris Skowronski, Steve Nelson, Rajesh Mongia, Howard...Technical Paper 3. DATES COVERED (From - To) 11/11 – 03/12 (etc.) 4. TITLE AND SUBTITLE An Octave Bandwidth, High PAE, Linear, Class J GaN High

  6. 2.45 GHz Class E Power Amplifier for a Transmitter Combining LINC and EER

    Directory of Open Access Journals (Sweden)

    M. Dirix

    2009-01-01

    Full Text Available A 10 W class-E RF power amplifier (PA is designed and fabricated using a Cree GaN HEMT. The proposed PA uses an innovative input circuit to optimize band with. At 2.45 GHz the PA achieves a PAE of 60 % at an outputpower of 40 dBm. The resulting amplifier is simulated and constructed using a transmissionline topology. Two of these amplifiers are fabricated on a single board for outphasing application. Their suitability for outphasing application and supply modulation is investigated. 

  7. New Driver For The Powerful Output Rf Amplifier Of Mmf Dtl Rf System

    CERN Document Server

    Kvasha, A I; Vassilyev, A G

    2004-01-01

    More than 30 years ago a few powerful vacuum tubes were specially designed and produced in the former design office Swetlana for the Moscow meson factory DTL RF system. Among them was tetrode GI-51A with output pulse RF power up to 300 kW at frequency 198.2 MHz, which was used as driver for RF power amplifier with output RF pulse power (2-3) MW. In connection with well-known events in our country manufacture of these tubes, including GI-51A was finished about 10 years ago. In "SED-SPb" (successor of the design office Swetlana) triode GI-57A was offered instead of GI-51A. In this paper results of calculations and design of RF amplifier with new triode are presented. Preliminary results of RF amplifier tests, also presented in the paper, showed that triode GI-57A will be able successfully used in the DTL RF system channels.

  8. A novel technique for electronic phasing of high power fiber amplifier arrays

    Science.gov (United States)

    Shay, T. M.; Baker, J. T.; Sanchez, Anthony D.; Robin, C. A.; Vergien, C. L.; Zeringue, C.; Gallant, D.; Lu, Chunte A.; Pulford, Benjamin; Bronder, T. J.; Lucero, Arthur

    2009-06-01

    We report high power phase locked fiber amplifier array using the Self-Synchronous Locking of Optical Coherence by Single-detector Electronic-frequency Tagging technique. We report the first experimental results for a five element amplifier array with a total locked power of more than 725-W. We will report on experimental measurements of the phase fluctuations versus time when the control loop is closed. The rms phase error was measured to be λ/60. Recent results will be reported. To the best of the authors' knowledge this is the highest fiber laser power to be coherently combined.

  9. 167 W, power scalable ytterbium-doped photonic bandgap fiber amplifier at 1178nm

    DEFF Research Database (Denmark)

    Olausson, Christina Bjarnal Thulin; Shirakawa, A.; Chen, M.

    2010-01-01

    An ytterbium-doped photonic bandgap fiber amplifier operating at the long wavelength edge of the ytterbium gain band is investigated for high power amplification. The spectral filtering effect of the photonic bandgap efficiently suppresses amplified spontaneous emission at the conventional...... ytterbium gain wavelengths and thus enables high power amplification at 1178 nm. A record output power of 167 W, a slope efficiency of 61% and 15 dB saturated gain at 1178 nm have been demonstrated using the ytterbium-doped photonic bandgap fiber....

  10. The Paralleling of High Power High Frequency Amplifier Based on Synchronous and Asynchronous Control

    Institute of Scientific and Technical Information of China (English)

    程荣仓; 刘正之

    2004-01-01

    The vertical position of plasma in the HT-7U Tokamak is inherently unstable. In order to realize active stabilization, the response rate of the high-power high-frequency amplifier feeding the active control coils must be fast enough. This paper analyzes the paralleling scheme of the power amplifier through two kinds of control mode. One is the synchronous control; the other is the asynchronous control. Via the comparison of the two kinds of control mode, both of their characteristics are given in the text. At last, the analyzed result is verified by a small power experiment.

  11. Generation of high energy and good beam quality pulses with a master oscillator power amplifier

    Institute of Scientific and Technical Information of China (English)

    Zhigang Li(李志刚); Z.Xiong; Nicholas Moore; Chen Tao; G.C.Lim; Weiling Huang(黄维玲); Dexiu Huang(黄德修)

    2004-01-01

    A high efficiency and high peak power laser system with short-pulse and good beam quality has been demonstrated by using a master oscillator power amplifier with two-pass amplification configuration. The master oscillator, end-pumped with a fiber-coupled laser diode array, provides low power but excellent beam quality pulses, and the amplifier boosts the pulse energy by orders without significant beam quality degradation. Short pulses of 8.5 ns with energy up to 130 mJ and approximately diffraction limited beam quality have been demonstrated.

  12. Single frequency 1083nm ytterbium doped fiber master oscillator power amplifier laser.

    Science.gov (United States)

    Huang, Shenghong; Qin, Guanshi; Shirakawa, Akira; Musha, Mitsuru; Ueda, Ken-Ichi

    2005-09-05

    Single frequency 1083nm ytterbium fiber master oscillator power amplifier system was demonstrated. The oscillator was a linear fiber cavity with loop mirror filter and polarization controller. The loop mirror with unpumped ytterbium fiber as a narrow bandwidth filter discriminated and selected laser longitudinal modes efficiently. Spatial hole burning effect was restrained by adjusting polarization controller appropriately in the linear cavity. The amplifier was 5 m ytterbium doped fiber pumped by 976nm pigtail coupled laser diode. The linewidth of the single frequency laser was about 2 KHz. Output power up to 177 mW was produced under the launched pump power of 332 mW.

  13. Efficient operation of a high-power {ital X}-band traveling wave tube amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Wang, P.; Xu, Z.; Ivers, J.D.; Nation, J.A.; Naqvi, S.; Schachter, L. [Cornell University, Ithaca, New York 14853 (United States)

    1999-10-01

    We report experimental results demonstrating 54{percent} power conversion efficiency (43{percent} energy conversion efficiency), from a two-stage {ital X}-band traveling wave tube amplifier designed for high-power operation. The first stage of the amplifier is a 12-cm-long Boron Nitride dielectric section used to modulate the electron beam. The second stage consists of a long high-phase-velocity bunching section followed by a short low-phase-velocity output section. Output powers of up to 78 MW with narrow spectrum width were obtained with {approximately}700 kV, {approximately}200 A beam. {copyright} {ital 1999 American Institute of Physics.}

  14. Piecewise-polynomial and cascade models of predistorter for linearization of power amplifier

    OpenAIRE

    2012-01-01

    To combat non-linear signal distortions in a power amplifier we suggest using predistorter with cascade structure in which first and second nodes have piecewise-polynomial and polynomial models. On example of linearizing the Winner–Hammerstein amplifier model we demonstrate that cascade structure of predistorter improves precision of amplifier’s linearization. To simplify predistorter’s synthesis the degree of polynomial model used in first node should be moderate, while precision should be i...

  15. Generation of sub-50 fs pulses from a high-power Yb-doped fiber amplifier.

    Science.gov (United States)

    Deng, Yujun; Chien, Ching-Yuan; Fidric, Bernard G; Kafka, James D

    2009-11-15

    We demonstrate the generation of 48 fs pulses with 18 W average power and 226 nJ of pulse energy from a Yb-doped fiber amplifier. The system uses a simple stretcher-free single-stage amplifier configuration operating in the parabolic pulse regime. The gain fiber length and pump wavelength are chosen in order to reduce the gain per unit length and generate both shorter pulses and higher pulse energy.

  16. High Power Uplink Amplifier for Deep Space Communications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Critical to the success of delivering on the promise of deep space optical communications is the creation of a stable and reliable high power multichannel optical...

  17. High Power Uplink Amplifier for Deep Space Communications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Critical to the success of delivering on the promise of deep space optical communications is the creation of a stable and reliable high power multichannel optical...

  18. Waveform measurement in mocrowave device characterization: impact on power amplifiers design

    Directory of Open Access Journals (Sweden)

    Roberto Quaglia

    2016-07-01

    Full Text Available This paper describes an example of a measurement setup enabling waveform measurements during the load-pull characterization of a microwave power device. The significance of this measurement feature is highlighted showing how waveform engineering can be exploited to design high efficiency microwave power amplifiers.

  19. High power picosecond vortex laser based on a large-mode-area fiber amplifier.

    Science.gov (United States)

    Tanaka, Yuichi; Okida, Masahito; Miyamoto, Katsuhiko; Omatsu, Takashige

    2009-08-03

    We present the production of picosecond vortex pulses from a stressed large-mode-area fiber amplifier for the first time. 8.5 W picosecond output with a peak power of approximately 12.5 kW was obtained at a pump power of 29 W. 2009 Optical Society of America.

  20. A 1-Watt Ku-Band Power Amplifier MMIC Using Cost-Effective Organic SMD Package

    NARCIS (Netherlands)

    Bessemoulin, A.; Parisot, M.; Quentin, P.; Saboureau, C.; Heijningen, M. van; Priday, J.

    2004-01-01

    This paper presents the design and performance of a compact 1-Watt Ku-band power amplifier MMIC implemented in a novel microwave organic power package, compatible with SMD assembly lines. Due to the use of simple materials, like RO4003 substrate and copper, it allows significant cost reduction for

  1. A 1-Watt Ku-Band Power Amplifier MMIC Using Cost-Effective Organic SMD Package

    NARCIS (Netherlands)

    Bessemoulin, A.; Parisot, M.; Quentin, P.; Saboureau, C.; Heijningen, M. van; Priday, J.

    2004-01-01

    This paper presents the design and performance of a compact 1-Watt Ku-band power amplifier MMIC implemented in a novel microwave organic power package, compatible with SMD assembly lines. Due to the use of simple materials, like RO4003 substrate and copper, it allows significant cost reduction for R

  2. Efficiency Enhancement of an Envelope Tracking Power Amplifier Combining Supply Shaping and Dynamic Biasing

    DEFF Research Database (Denmark)

    Tafuri, Felice Francesco; Sira, Daniel; Jensen, Ole Kiel

    2013-01-01

    of the input envelope by means of two shaping functions jointly designed on the basis of a single-tone characterization. The presented technique is demonstrated by means of measurements on a commercial GaAs HBT power amplifier. Measured results showed a PA power added efficiency (PAE) of 51.9%, an error vector...

  3. Millimeter‐wave INP DHBT power amplifier based on power‐optimized cascode configuration

    DEFF Research Database (Denmark)

    Johansen, Tom K.; Yan, Lei; Dupuy, Jean‐Yves

    2013-01-01

    This letter describes the use of a power‐optimized cascode configuration for obtaining maximum output power at millimeter‐wave (mm‐wave) frequencies for a two‐way combined power amplifier (PA). The PA has been fabricated in a high‐speed InP double heterojunction bipolar transistor technology...

  4. Approaches to building single-stage AC/AC conversion switch-mode audio power amplifiers

    DEFF Research Database (Denmark)

    Ljusev, Petar; Andersen, Michael Andreas E.

    2004-01-01

    This paper discusses the possible topologies and promising approaches towards direct single-phase AC-AC conversion of the mains voltage for audio applications. When compared to standard Class-D switching audio power amplifiers with a separate power supply, it is expected that direct conversion...

  5. Design Methodology of High Power Distributed Amplifier Employing Broadband Impedance Transformer

    DEFF Research Database (Denmark)

    Narendra, Kumar; Zhurbenko, Vitaliy; Collantes, Juan Mari;

    2009-01-01

    A novel topology of a high power distributed amplifier (DA) in combination with a broadband impedance transformer is presented. The advantages of the proposed topology are explored analytically and verified by a full-wave 3D simulations. Stability of the high power DA is verified with the pole...

  6. Integrating switch mode audio power amplifiers and electro dynamic loudspeakers for a higher power efficiency

    DEFF Research Database (Denmark)

    Poulsen, Søren; Andersen, Michael Andreas E.

    2004-01-01

    The work presented in this paper is related to integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker's voice coil as output filter, and the magnetic structure as heatsink for the amplifier.......The work presented in this paper is related to integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker's voice coil as output filter, and the magnetic structure as heatsink for the amplifier....

  7. Finite-duration Seeding Effects in Powerful Backward Raman Amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    N.A. Yampolsky; V.M. Malkin; N.J. Fisch

    2003-07-14

    In the process of backward Raman amplification (BRA), the leading layers of the seed laser pulse can shadow the rear layers, thus weakening the effective seeding power and affecting parameters of output pulses in BRA. We study this effect numerically and also analytically by approximating the pumped pulse by the ''*-pulse'' manifold of self-similar solutions. We determine how the pumped pulse projection moves within the *-pulse manifold, and describe quantitatively the effective seeding power evolution. Our results extend the quantitative theory of BRA to regimes where the effective seeding power varies substantially during the amplification. These results might be of broader interest, since the basic equations, are general equations for resonant 3-wave interactions.

  8. Design of a new VHF RF power amplifier system for LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Lyles, John T M [Los Alamos National Laboratory

    2010-01-01

    A major upgrade is replacing much of the 40 year-old proton drift tube linac RF system with new components at the Los Alamos Neutron Science Center (LANSCE). When installed, the new system will reduce the total number of electron power tubes from twenty-four to eight in the RF powerplant. A new 200 MHz high power cavity amplifier has being developed at LANSCE. This 3.2 MW final power amplifier (FPA) uses a Thales TH628 Diacrode{reg_sign}, a state-of-the-art tetrode that eliminates the large anode modulator of the triode-based FPA that has been in use for four decades. Drive power for the FPA is provided by a new tetrode intermediate power amplifier (and a solid-state driver stage). The new system has sufficient duty-factor capability to allow LANSCE to return to 1 MW beam operation. Prototype RF power amplifiers have been designed, fabricated, and assembled, and are being tested. High voltage DC power became available through innovative re-engineering of an installed system. Details of the electrical and mechanical design of the FPA and ancillary systems are discussed.

  9. Concentric Parallel Combining Balun for Millimeter-Wave Power Amplifier in Low-Power CMOS with High-Power Density

    Science.gov (United States)

    Han, Jiang-An; Kong, Zhi-Hui; Ma, Kaixue; Yeo, Kiat Seng; Lim, Wei Meng

    2016-11-01

    This paper presents a novel balun for a millimeter-wave power amplifier (PA) design to achieve high-power density in a 65-nm low-power (LP) CMOS process. By using a concentric winding technique, the proposed parallel combining balun with compact size accomplishes power combining and unbalance-balance conversion concurrently. For calculating its power combination efficiency in the condition of various amplitude and phase wave components, a method basing on S-parameters is derived. Based on the proposed parallel combining balun, a fabricated 60-GHz industrial, scientific, and medical (ISM) band PA with single-ended I/O achieves an 18.9-dB gain and an 8.8-dBm output power at 1-dB compression and 14.3-dBm saturated output power ( P sat) at 62 GHz. This PA occupying only a 0.10-mm2 core area has demonstrated a high-power density of 269.15 mW/mm2 in 65 nm LP CMOS.

  10. Debugging of Class-D Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Crone, Lasse; Pedersen, Jeppe Arnsdorf; Mønster, Jakob Døllner

    2012-01-01

    Determining and optimizing the performance of a Class-D audio power amplier can be very dicult without knowledge of the use of audio performance measuring equipment and of how the various noise and distortion sources in uence the audio performance. This paper gives an introduction on how to measure...

  11. The power stability of a fiber amplifier based on a multifunction card and PID control program

    Science.gov (United States)

    Zhang, Linjie; Yang, Wenguang; Zhang, Hao; Zhao, JianMing; Jia, Suotang

    2016-06-01

    The power stability of a fiber amplifier was significantly improved by means of simultaneously controlling the current of a fiber amplifier and the diffraction efficiency of an acousto-optical modulator. The real-time fluctuation of laser power was recorded by a multifunction card and processed by a proportional-integral-derivative (PID) control program. The feedback loop voltage was introduced to the fiber laser amplifier and acoustic-optic modulator through the analog output of the multifunction card. The control method based on a multifunction card and PID program has good scalability, flexibility and reliability for the complex system on the condition in which the frequency and power of the laser need to be precisely stabilized.

  12. Inverse class-f power amplifier using slot resonators as a harmonic filter

    Directory of Open Access Journals (Sweden)

    Rassokhina Yu. V.

    2014-06-01

    Full Text Available The authors proposed and experimentally verified the power amplifier circuit of inverse class F (F–1 based on GaN transistor NPTB00004, operating at 1,7 GHz. The novelty of this scheme is the application of a three-layer structure based on slot rectangular shaped resonators in the ground plane of the microstrip transmission line as a filter of higher harmonics. To control the levels of the second and third harmonics in the output signal spectrum and simultaneously to match the 50 ohm load at the operating frequency of the amplifier, a planar periodic structure is used, consisting of two slot resonators of different lengths. Power added efficiency for experimental model of the amplifier is 60% at an output power of 3.9 W and a gain factor of 13 dB.

  13. A compact 10 kW solid-state RF power amplifier at 352 MHz

    Science.gov (United States)

    Dancila, Dragos; Hoang Duc, Long; Jobs, Magnus; Holmberg, Måns; Hjort, Adam; Rydberg, Anders; Ruber, Roger

    2017-07-01

    A compact 10 kW RF power amplifier at 352 MHz was developed at FREIA for the European Spallation Source, ESS. The specifications of ESS for the conception of amplifiers are related to its pulsed operation: 3.5 ms pulse length and a duty cycle of 5%. The realized amplifier is composed of eight kilowatt level modules, combined using a planar Gysel 8-way combiner. The combiner has a low insertion loss of only 0.2 dB, measured at 10 kW peak power. Each module is built around a commercially available LDMOS transistor in a singleended architecture. During the final tests, a total output peak power of 10.5 kW was measured.

  14. Low-cost high-efficient 10-Watt X-band high-power amplifier

    NARCIS (Netherlands)

    Bent, G. van der; Hek, A.P. de; Bessemoulin, A.; Vliet, F.E. van

    2009-01-01

    A high power X-band amplifier with an output power over 10 Watts and a Power Added Efficiency (PAE) in excess of 40 percent has been developed. The design was fabricated in a 0.25 μm pHEMT GaAs process (WIN Semiconductor PP25-01). The small die area in combination with a 6-inch wafer technology prov

  15. Benefits of active transmit balanced antenna fed by differential power amplifier

    OpenAIRE

    Sagor, Md. Hasanuzzaman; Callaghan, Peter

    2014-01-01

    A differential amplifier feeding a balanced antenna is investigated experimentally. This approach would suit modern RFIC design rather than using a 50Ω unbalanced connection. As such the balun or power-combining network is eliminated resulting in a compact RF front-end design with wider bandwidth and lower losses. Experimental result shows that this technique promises higher output power compared to conventional feeding approach while using same RFIC and same power supply.

  16. Design and Research on Sigma-Delta Digital-to-Analog Converters for Audio Power Amplifiers

    OpenAIRE

    Puidokas, Vytenis

    2011-01-01

    The dissertation investigates the issues of analyzing a digital Sigma-Delta digital-to-analog converter (DAC) for audio power amplifiers. The main objects of research include a digital Sigma-Delta audio power DAC, improvement of its structure and an experimental research. The primary purpose of the dissertation is to suggest methods for improvement the structure of digital Sigma-Delta audio power DAC interpolator and the converter analysis. Disertacijoje nagrinėjami Sigma-Delta skaitmenini...

  17. A high efficiency PWM CMOS class-D audio power amplifier

    Institute of Scientific and Technical Information of China (English)

    朱樟明; 刘帘曦; 杨银堂; 雷晗

    2009-01-01

    Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5 μm CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD+N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 μA. The active area of the class-D audio power amplifier is about 1.47 × 1.52 mm2. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.

  18. A high efficiency PWM CMOS class-D audio power amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Zhangming; Liu Lianxi; Yang Yintang [Institute of Microelectronics, Xidian University, Xi' an 710071 (China); Lei Han, E-mail: zmyh@263.ne [Xi' an Power-Rail Micro Co., Ltd, Xi' an 710075 (China)

    2009-02-15

    Based on the difference close-loop feedback technique and the difference pre-amp, a high efficiency PWM CMOS class-D audio power amplifier is proposed. A rail-to-rail PWM comparator with window function has been embedded in the class-D audio power amplifier. Design results based on the CSMC 0.5 mum CMOS process show that the max efficiency is 90%, the PSRR is -75 dB, the power supply voltage range is 2.5-5.5 V, the THD+N in 1 kHz input frequency is less than 0.20%, the quiescent current in no load is 2.8 mA, and the shutdown current is 0.5 muA. The active area of the class-D audio power amplifier is about 1.47 x 1.52 mm{sup 2}. With the good performance, the class-D audio power amplifier can be applied to several audio power systems.

  19. High-gain Yb:YAG amplifier for ultrashort pulse laser at high-average power

    Science.gov (United States)

    Vetrovec, John; Copeland, Drew A.; Litt, Amardeep S.; Du, Detao

    2016-03-01

    We report on a Yb:YAG laser amplifier for ultrashort pulse applications at kW-class average power. The laser uses two large-aperture, disk-type gain elements fabricated from composite ceramic YAG material, and a multi-pass extraction architecture to obtain high gain in a chirped-pulse amplification system. The disks are edge-pumped, thus allowing for reduced doping of host material with laser ions, which translates to lower lasing threshold and lower heat dissipation in the Yb:YAG material. The latter makes it possible to amplify a near diffraction-limited seed without significant thermo-optical distortions. This work presents results of testing the laser amplifier with relay optics configured for energy extraction with up to 40 passes through the disks. Applications for the ultrashort pulse laser amplifier include producing laser-induced plasma channel, laser material ablation, and laser acceleration of atomic particles.

  20. High-power, 1-ps, all-Yb:YAG thin-disk regenerative amplifier.

    Science.gov (United States)

    Fattahi, Hanieh; Alismail, Ayman; Wang, Haochuan; Brons, Jonathan; Pronin, Oleg; Buberl, Theresa; Vámos, Lénárd; Arisholm, Gunnar; Azzeer, Abdallah M; Krausz, Ferenc

    2016-03-15

    We report a 100 W, 20 mJ, 1-ps, all-Yb:YAG thin-disk regenerative amplifier seeded by a microjoule-level Yb:YAG thin-disk Kerr-lens mode-locked oscillator. The regenerative amplifier is implemented in a chirped pulse amplification system and operates at an ambient temperature in air, delivering ultrastable output pulses at a 5 kHz repetition rate and with a root mean square power noise value of less than 0.5%. Second harmonic generation of the amplifier's output in a 1.5 mm-thick BBO crystal results in more than 70 W at 515 nm, making the system an attractive source for pumping optical parametric chirped pulse amplifiers in the visible and near-infrared spectral ranges.

  1. Active Electromagnetic Interference Cancelation for Automotive Switch-Mode Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Knott, Arnold; Pfaffinger, Gerhard; Andersen, Michael A. E.

    2009-01-01

    . Electromagnetic interference between switch-mode audio power amplifiers and receivers show the same physical obstacle as the described ANC endeavors are targeting. The principle of active electromagnetic interference cancelation (AEC) is derived in this paper on a theoretical basis with verifications...... in simulation and experiment. The resulting switch-mode audio power amplifier of this experiment keeps its high efficiency and is able to deliver the signal with less than 0.1 % distortion, while improving the source of electromagnetic interference by 15 dB....

  2. Design of Digital Predistortion Technique for RF Power Amplifier using Memory Polynomial

    Directory of Open Access Journals (Sweden)

    Er. Sweety Badhwar

    2014-09-01

    Full Text Available Linearization of power amplifier has been an area of intense research from the last many years. The various types of linearization techniques are available for linearising PA but Digital Predistortion technique has been observed as one of the most common and effective method. But due to the issues like memory effects and exact characterization of non-linear behaviour of power amplifier, the implementation of existing predistortion technique suffers. So in this paper, a digital predistorter based on memory polynomial has been proposed that takes care of above mentioned issues. The presented technique is easy to implement and simple.

  3. Linearization and efficiency enhancement techniques for silicon power amplifiers from RF to mmW

    CERN Document Server

    Kerhervé, Eric

    2015-01-01

    This book provides an overview of current efficiency enhancement and linearization techniques for silicon power amplifier designs. It examines the latest state of the art technologies and design techniques to address challenges for RF cellular mobile, base stations, and RF and mmW WLAN applications. Coverage includes material on current silicon (CMOS, SiGe) RF and mmW power amplifier designs, focusing on advantages and disadvantages compared with traditional GaAs implementations. With this book you will learn: The principles of linearization and efficiency improvement techniquesThe arch

  4. Low Power and Fast Transient High Swing CMOS Telescopic Operational Amplifier

    Directory of Open Access Journals (Sweden)

    Akshay Kumar Kansal

    2015-12-01

    Full Text Available CMOS telescopic operational amplifier with high-swing and high-performance is described in this paper. The swing is attained by using the tail and current source-transistors in deep-linear region. The resultant deprivation in parameters like differential gain, CMRR and added characteristics are recompensed by using regulatedcascode differential gain enhancement and a replica-tail feedback technique. Operating at power supply of 3.3V, the power consumption, slew rate and settling time are improved using transmission controlled pass circuitry and level amplifier. It is shown through simulations that the Op-Amp preserves its high CMRR and unity gain frequency.

  5. High-Power Er3+/Yb3+ Codoped Double-Cladding Fibre Amplifier with More Than 2 W Output Power

    Institute of Scientific and Technical Information of China (English)

    LIU Yan-Ge; FENG Xin-Huan; LI Li-Jun; LI Yao; YUAN Shu-Zhong; KAI Gui-Yun; LI Yi-Gang; DONG Xiao-Yi

    2005-01-01

    @@ A high-power Er3+/Yb3+-codoped double-cladding all-fibre amplifier was successfully demonstrated and experimentally investigated. The amplifier could be operated with a maximum output power of 2.18 W and 2.11 W at 1541nm and 1550nm wavelengths, respectively, when the maximum pump power was 6.07W. The power conversion efficiency was up to 35.6% and 34.4% at the two wavelengths, respectively. The output power and the gain were greater than 2.00 W and 20.0dB, respectively, in the wavelength range from 1539nm to 1565nm for 20.0mW input signal power. The gain fluctuation and the noise figure around 1550nm wavelength were less than 0.3 dB and 6.0 dB, respectively.

  6. Studies on Nd∶YAG Single-pass Amplifiers for High-power Q-switched Laser System

    Institute of Scientific and Technical Information of China (English)

    CAO Sansong(曹三松); ZHANG Xiangyang(张向阳); HUANG Yanlin(黄燕琳); LI Guangrong(李光荣); SU Xinzhi(苏心智)

    2002-01-01

    The output of Nd∶YAG single-pass laser amplifiers is studied analytically and experimentally. Methods of analysis for single-pass Nd∶YAG laser amplifier are presented. A flashlamp-pumped Q-switched Nd∶YAG oscillator/amplifier laser system has been developed with the average output power of 121.5 W.

  7. Analytical Design Equations for Class-E Power Amplifiers with Finite DC-Feed Inductance and Switch On-Resistance

    NARCIS (Netherlands)

    Acar, Mustafa; Annema, Anne Johan; Nauta, Bram

    2007-01-01

    Many critical design trade-offs of the class-E power amplifier (e.g power efficiency) are influenced by the switch on-resistance and the value of dc-feed drain inductance. In literature, the time-domain mathematical analyses of the class-E power amplifier with finite dc-feed inductance assume zero s

  8. A digitally controlled power amplifier with neutralization capacitors for Zigbee™ applications

    Science.gov (United States)

    Fei, Jia; Shengxi, Diao; Xuejuan, Zhang; Zhongqian, Fu; Fujiang, Lin

    2012-12-01

    This paper presents a single chip CMOS power amplifier with neutralization capacitors for Zigbee™ system according to IEEE 802.15.4. A novel structure with digital interface is adopted, which allows the output power of a PA to be controlled by baseband signal directly, so there is no need for DAC. The neutralization capacitors will increase reverse isolation. The chip is implemented in SMIC 0.18 μm CMOS technology. Measurement shows that the proposed power amplifier has a 13.5 dB power gain, 3.48 dBm output power and 35.1% PAE at P1dB point. The core area is 0.73 × 0.55 mm2.

  9. A High-Voltage class-D power amplifier with switching frequency regulation for improved high-efficiency output power range

    NARCIS (Netherlands)

    Ma, Haifeng; Zee, van der Ronan; Nauta, Bram

    2015-01-01

    This paper describes the power dissipation analysis and the design of an efficiency-improved high-voltage class-D power amplifier. The amplifier adaptively regulates its switching frequency for optimal power efficiency across the full output power range. This is based on detecting the switching outp

  10. Broadband Fiber Raman Power-Amplifier for Narrow Linewidth Tunable Seed Lasers Used in Spectroscopic Sensing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose an energy and space efficient high power continuous wave (cw) narrow linewidth broadband fiber Raman amplifier (FRA) with spectrally tunable...

  11. Compressed sensing based joint-compensation of power amplifier's distortions in OFDMA cognitive radio systems

    KAUST Repository

    Ali, Anum Z.

    2013-12-01

    Linearization of user equipment power amplifiers driven by orthogonal frequency division multiplexing signals is addressed in this paper. Particular attention is paid to the power efficient operation of an orthogonal frequency division multiple access cognitive radio system and realization of such a system using compressed sensing. Specifically, precompensated overdriven amplifiers are employed at the mobile terminal. Over-driven amplifiers result in in-band distortions and out of band interference. Out of band interference mostly occupies the spectrum of inactive users, whereas the in-band distortions are mitigated using compressed sensing at the receiver. It is also shown that the performance of the proposed scheme can be further enhanced using multiple measurements of the distortion signal in single-input multi-output systems. Numerical results verify the ability of the proposed setup to improve error vector magnitude, bit error rate, outage capacity and mean squared error. © 2011 IEEE.

  12. Third-order Intermodulation Reduction in Mobile Power Amplifiers by the First Stage Bias Control

    Directory of Open Access Journals (Sweden)

    J. H. Jung

    2012-06-01

    Full Text Available In this paper, the third order intermodulation distortion (IMD3 of three-stage power amplifier (PA is analyzed using the Volterra series. The analysis explains how the total IMD3 of the three-stage power amplifier can be reduced by the first-stage bias condition. The three-stage PA, which is fabricated using InGaP/GaAs hetero-junction bipolar transistor (HBT, operates with an optimized first driver stage bias for higher P1dB and good gain flatness. The power amplifier has been designed for 1626.5 MHz~1660.5 MHz satellite mobile communications. With π/4 DQPSK modulation signals, this PA can deliver a highly linear output power of 33 dBm from 3.6V supply voltage. At 33 dBm output power, it shows a gain of 31.9 dB, a power-added efficiency (PAE of 39.8%, an adjacent channel power ratio (ACPR of -28.2 dBc at a 31.25 KHz offset frequency.

  13. Thermo-optical effects in high-power Ytterbium-doped fiber amplifiers

    DEFF Research Database (Denmark)

    Hansen, Kristian Rymann; Alkeskjold, Thomas Tanggaard; Broeng, Jes

    2011-01-01

    We investigate the effect of temperature gradients in high-power Yb-doped fiber amplifiers by a numerical beam propagation model, which takes thermal effects into account in a self-consistent way. The thermally induced change in the refractive index of the fiber leads to a thermal lensing effect,...

  14. Generalized Design Equations for Class-E Power Amplifiers with Finite DC Feed Inductance

    NARCIS (Netherlands)

    Acar, M.; Annema, A.J.; Nauta, B.

    2006-01-01

    In literature, it is widely accepted that the design of Class-E Power Amplifier (PA) with finite dc feed inductance requires a long iterative solution procedure. To avoid such iterative solution methods, analytical design equations should be known. The problem associated with the finite dc feed indu

  15. Efficiency Investigation of Switch Mode Power Amplifier Drving Low Impedance Transducers

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Schneider, Henrik; Knott, Arnold;

    2015-01-01

    the amplifier rail voltage requirement as a function of the voice coil nominal resistance is presented. The method is based on a crest factor analysis of music signals and estimation of the electrical power requirement from a specific target of the sound pressure level. Experimental measurements confirms a huge...

  16. 47 CFR 15.204 - External radio frequency power amplifiers and antenna modifications.

    Science.gov (United States)

    2010-10-01

    ... person shall use, manufacture, sell or lease, offer for sale or lease (including advertising for sale or lease), or import, ship, or distribute for the purpose of selling or leasing, any external radio... separate product. (1) An external radio frequency power amplifier may be marketed for individual...

  17. An audio FIR-DAC in a BCD process for high power Class-D amplifiers

    NARCIS (Netherlands)

    Doorn, T.S.; Tuijl, van E.; Schinkel, D.; Annema, A.J.; Berkhout, M.; Nauta, B.

    2005-01-01

    A 322 coefficient semi-digital FIR-DAC using a 1-bit PWM input signal was designed and implemented in a high voltage, audio power bipolar CMOS DMOS (BCD) process. This facilitates digital input signals for an analog class-D amplifier in BCD. The FIR-DAC performance depends on the ISI-resistant natur

  18. An audio FIR-DAC in a BCD process for high power Class-D amplifiers

    NARCIS (Netherlands)

    Doorn, T.S.; van Tuijl, Adrianus Johannes Maria; Schinkel, Daniel; Annema, Anne J.; Berkhout, M.; Berkhout, M.; Nauta, Bram

    A 322 coefficient semi-digital FIR-DAC using a 1-bit PWM input signal was designed and implemented in a high voltage, audio power bipolar CMOS DMOS (BCD) process. This facilitates digital input signals for an analog class-D amplifier in BCD. The FIR-DAC performance depends on the ISI-resistant

  19. A power-efficient audio amplifier combining switching and linear techniques

    NARCIS (Netherlands)

    van der Zee, Ronan A.R.; van Tuijl, Adrianus Johannes Maria

    1999-01-01

    Integrated class-D audio amplifiers are very power efficient but require an external LC reconstruction filter, which prevents further integration. Also due to this filter, large feedback factors are hard to realize, so that the load influences the distortion and transfer characteristics. The 30 W

  20. A power-efficient audio amplifier combining switching and linear techniques

    NARCIS (Netherlands)

    van der Zee, Ronan A.R.; van Tuijl, Adrianus Johannes Maria

    1999-01-01

    Integrated class-D audio amplifiers are very power efficient but require an external LC reconstruction filter, which prevents further integration. Also due to this filter, large feedback factors are hard to realize, so that the load influences the distortion and transfer characteristics. The 30 W am

  1. Audio power amplifier techniques with energy efficient power conversion. Vol. 1

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Karsten

    1998-04-01

    A fundamental study of both analog and digital pulse modulation methods is carried out. A novel class of multi-level pulse modulation methods - Phase Shifted Carrier Pulse Width Modulation (PSCPWM) - is introduced and show to have several advantageous features, primarily caused by the much improved synthesis of the modulating signal. Enhanced digital pulse modulation methods for digital Pulse Modulation Amplifier (PMA) systems are investigated, and a simple methodology for digital PWM modulator synthesis is devised. It is concluded, that the modulator performance is not a limitation in the system, regardless of the domain of modulator implementation. Power conversion in PMA systems is adressed from the perspective of both linearity and efficienty optimization. Based on detailed studies of the distortion mechanisms in the power conversion stage it is concluded, that this is the fundamental limitation on system performance due to several physical limitations. The analysis of general power stage efficiency concludes that dramatic improvements in energy efficiency are possible with PMA systems that are optimized for efficiency. A control system design methodology is devised as a platform for synthesis of robust control systems. Investigations of three fundamental control structures show that even simple control systems offer a remarkable value, although the considered topologies also have their limitations which is verified by practical evaluation in hardware. A novel control method is introduced - Multivariable Enhanced Cascade Control (MECC). MECC provides flexible control over all essential system parameters and is furthermore simple in realization. Practical evaluation of a MECC based PMA shows state-of-the-art performance. The application of non-linear control methods is investigated with the introduction of an enhanced non-linear control/modulator topology. Although the non-linear controller is theoretically interesting, the method proves to suffer from various

  2. Efficiency Enhancement of an Envelope Tracking Power Amplifier Combining Supply Shaping and Dynamic Biasing

    DEFF Research Database (Denmark)

    Tafuri, Felice Francesco; Sira, Daniel; Jensen, Ole Kiel

    2013-01-01

    This paper presents a new method to improve the performance of envelope tracking (ET) power amplifiers (PAs). The method consists of combining the supply modulation that characterizes the envelope tracking architecture with supply shaping and dynamic biasing. The inclusion of dynamic biasing allows...... of the input envelope by means of two shaping functions jointly designed on the basis of a single-tone characterization. The presented technique is demonstrated by means of measurements on a commercial GaAs HBT power amplifier. Measured results showed a PA power added efficiency (PAE) of 51.9%, an error vector...... magnitude (EVM) of 1.2% and an adjacent channel power ratio (ACPR) of -39.4/-43.5 dBc. The presented transmitter architecture allowed an improvement of 12% PAE compared to a classical ET transmitter where the measured PA was biased in class-AB, maintaining the linearity indicators....

  3. Low Power and Fast Transient High Swing CMOS Telescopic Operational Amplifier

    OpenAIRE

    Akshay Kumar Kansal; Asst Prof. Gayatri Sakya

    2015-01-01

    CMOS telescopic operational amplifier with high-swing and high-performance is described in this paper. The swing is attained by using the tail and current source-transistors in deep-linear region. The resultant deprivation in parameters like differential gain, CMRR and added characteristics are recompensed by using regulatedcascode differential gain enhancement and a replica-tail feedback technique. Operating at power supply of 3.3V, the power consumption, slew rate and settling t...

  4. Extended Cann Model for Behavioral Modeling of Envelope Tracking Power Amplifiers

    DEFF Research Database (Denmark)

    Tafuri, Felice Francesco; Larsen, Torben

    2013-01-01

    This paper deals with behavioral modeling of power amplifiers (PAs) for envelope tracking (ET) applications. In such a scenario, the power supply modulation brings in several additional challenges for the system design and, similarly, it becomes more difficult to obtain an accurate and general PA...... by the ET operation. The model performance is tested modeling data-sets acquired from an ET test bench including a commercial RFMD PA and an envelope modulator designed using a commercial IC from TI....

  5. High-power linearly-polarized picosecond thulium-doped all-fiber master-oscillator power-amplifier.

    Science.gov (United States)

    Liu, Jiang; Liu, Chen; Shi, Hongxing; Wang, Pu

    2016-06-27

    We demonstrated a linearly-polarized picosecond thulium-doped all-fiber-integrated master-oscillator power-amplifier system, which yielded 240 W of average output power at 127 MHz repetition rate. The seed source is a passively mode-locked polarization-maintaining thulium-doped all-fiber oscillator with a nearly transform-limited pulse duration of 10 ps. In combination with a pre-chirp fiber having a positive group velocity dispersion and a three stage polarization-maintaining thulium-doped all-fiber amplifier, output pulse energies up to 1.89 µJ with 42 kW pulse peak power are obtained without the need of complex free-space stretcher or compressor setups. To the best of our knowledge, this is the highest average output power ever reported for a picosecond all-fiber-integrated laser at 2 µm wavelength region.

  6. Dynamic Floating Output Stage for Low Power Buffer Amplifier for LCD Application

    Directory of Open Access Journals (Sweden)

    Hari Shanker Srivastava

    2015-02-01

    Full Text Available This topic proposes low-power buffer means low quiescent current buffer amplifier. A dynamic floating current node is used at the output of two-stage amplifier to increase the charging and discharging of output capacitor as well as settling time of buffer. It is designed for 10 bit digital analog converter to support for LCD column driver it is implemented in 180 nm CMOS technology with the quiescent current of 5 µA for 30 pF capacitance, the settling time calculated as 4.5µs, the slew rate obtained as 5V/µs and area on chip is 30×72µ

  7. Efficiency of Switch-Mode Power Audio Amplifiers - Test Signals and Measurement Techniques

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Knott, Arnold; Andersen, Michael A. E.

    2016-01-01

    Switch-mode technology is greatly used for audio amplification. This is mainly due to the great efficiency this technology offers. Normally the efficiency of a switch-mode audio amplifier is measured using a sine wave input. However this paper shows that sine waves represent real audio very poorly....... An alternative signal is proposed for test purposes. The efficiency of a switch-mode power audio amplifier is modelled and measured with both sine wave and the proposed test signal as inputs. The results show that the choice of switching devices with low on resistances are unfairly favored when measuring...

  8. Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges

    Directory of Open Access Journals (Sweden)

    Mahammad A. Hannan

    2014-12-01

    Full Text Available With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil’s mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning

  9. Automatic frequency controller for power amplifiers used in bio-implanted applications: issues and challenges.

    Science.gov (United States)

    Hannan, Mahammad A; Hussein, Hussein A; Mutashar, Saad; Samad, Salina A; Hussain, Aini

    2014-12-11

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  10. Tri-state Modulation Power Driving of Electro-hydraulic Proportional Amplifier

    Institute of Scientific and Technical Information of China (English)

    NIE Yong; WANG Qingfeng

    2009-01-01

    Switch electro-hydraulic proportional amplifier(PA) widely employs single switch modulation power driving(SSMPD) or reverse discharging power driving(RDPD) at present. SSMPD has slow dynamic response, and can't adjust independently the dither signal's amplitude and frequency;RDPD accelerates the current decay;consequently, it increases current ripple and power loss. For the purpose of solving the above mentioned problem, the tri-state modulation power driving(TSMPD) scheme was proposed for improving the performance of power driving. Detailedly, the hardware circuit for the tri-state modulation power driving is designed;the tri-state modulation algorithm is realized by digital signal processor(DSP). The tri-state modulation power driving is investigated by experiments, comparetive experiments among the single switch modulation power driving(SSMPD), reverse discharging power driving(RDPD), and the TSMPD are implemented, and the experimental results demonstrate that the linearity error of TSMDP meets the requirement of PA;the current response of TSMSP is the best;the amplitude of ripple current of the TSMPD can be reduced without increasing frequency of PWM, in addition, dither signal amplitude and frequency can be adjusted independently for each other. It is very meaningful to guide the development of high performance proportional amplifier for high frequency response proportional solenoid.

  11. Efficiency Investigation of Switch Mode Power Amplifier Drving Low Impedance Transducers

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Schneider, Henrik; Knott, Arnold

    2015-01-01

    The typical nominal resistance span of an electro dynamic transducer is 4 Ω to 8 Ω. This work examines the possibility of driving a transducer with a much lower impedance to enable the amplifier and loudspeaker to be directly driven by a low voltage source such as a battery. A method for estimating...... the amplifier rail voltage requirement as a function of the voice coil nominal resistance is presented. The method is based on a crest factor analysis of music signals and estimation of the electrical power requirement from a specific target of the sound pressure level. Experimental measurements confirms a huge...... performance leap in terms of efficiency compared to a conventional battery driven sound system. Future optimization of low voltage, high current amplifiers for low impedance loudspeaker drivers are discussed....

  12. F-band, High-Efficiency GaN Power Amplifier for the Scanning Microwave Limb Sounder and SOFIA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a 4-watt Solid-State Power Amplifier (SSPA) operating at F-band (106-114 GHz) with a power-added efficiency (PAE) of greater...

  13. 0.18μm CMOS Low Voltage Power Amplifier For WSN Application

    Directory of Open Access Journals (Sweden)

    Wu Chenjian

    2013-08-01

    Full Text Available This paper presents the design of a Class A/B power amplifier (PA for 2.4-2.4835GHz Wireless Sensor Network (WSN system in 0.18μm CMOS technology. The PA adopts the single-stage differential structure and the output power of the PA can be controlled by switching the sizes of transistors. Seven different level of output power can be obtained through a three- bit control code. The tested results shows that the proposed PA achieves power added efficiency (PAE of 26.73% while delivering an output power of 6.35dBm at 1dB compression point. Its power gain is 15.87dB. With a low DC voltage supply of 1V, its power consumption is 15.3mW. The PA die size is 1070×610μm2.

  14. Frequency dependent loss analysis and minimization of system losses in switchmode audio power amplifiers

    DEFF Research Database (Denmark)

    Yamauchi, Akira; Knott, Arnold; Jørgensen, Ivan Harald Holger

    2014-01-01

    In this paper, frequency dependent losses in switch-mode audio power amplifiers are analyzed and a loss model is improved by taking the voltage dependence of the parasitic capacitance of MOSFETs into account. The estimated power losses are compared to the measurement and great accuracy is achieved....... By choosing the optimal switching frequency based on the proposed analysis, the experimental results show that system power losses of the reference design are minimized and an efficiency improvement of 8 % in maximum is achieved without compromising audio performances....

  15. Study of high power, two-stage, TWT X-band amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Wang, P.; Golkowski, C.; Hayashi, Y.; Ivers, J.D.; Nation, J.A.; Schachter, L.

    1999-07-01

    A disk loaded slow wave structure with a cold wave phase (without electron beam) velocity of the TM{sub 01} wave greater than the speed of light (1.05c) is used as the electron bunching stage of a two stage X-band amplifier. The high phase velocity section produces well defined electron bunches. The second section, where the cold wave phase velocity is (0.84c), i.e., less than beam velocity of 0.91c, is used to generate the high output power microwave radiation. The tightly bunched beam from the high phase velocity section enhances the beam energy conversion into microwave radiation compared to that obtained with a synchronous electron-wave bunches. The amplifier is driven by a 7mm diameter 750 kV, 500A pencil electron beam. The structure, which has a 4 GHz bandwidth, produces an amplified output with a power in the range of 20--60 MW. At higher output powers (>60MW) pulse shortening develops. The authors suspect that the pulse shortening is a result of excitation of the hybrid mode, HEM{sub 11}, which overlaps (about 0.5 GHz separation) with the frequency domain of the desired TM{sub 0.1} mode. A new amplifier with similar phase velocity characteristics but with a 1 GHz bandwidth and an HEM{sub 11}, TM{sub 01} mode frequency separation of 3.3 GHz has been designed and constructed. The interaction frequency for the HEM mode is above the passband of the TM mode. Testing is in progress. The performance of the new amplifier will be compared with results obtained using the earlier configuration.

  16. A 5.2 GHz RF combined power amplifier with fully integrated on-chip impedance matching Wilkinson power combiner and splitter

    OpenAIRE

    Kaymaksüt, Ercan; Kaymaksut, Ercan

    2008-01-01

    In this thesis a 5.2 GHz combined power amplifier is designed for Wireless Local Area Network (WLAN) application. A new on-chip power combining technique by using impedance matching Wilkinson power divider circuits will be presented. Two impedance matching Wilkinson power dividers are employed for matching the input and output impedances of the amplifier to 50 (omega)Ω as well as splitting the input power into two amplifiers and combining their output powers. A 5.2 GHz fully integrated class-...

  17. High-Power and Low-Noise 10-GHz All-Active Monolithic Mode-Locked Lasers with Surface Etched Bragg Grating

    DEFF Research Database (Denmark)

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter.......We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter....

  18. A new principle for a high-efficiency power audio amplifier for use with a digital preamplifier

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    1987-01-01

    The use of class-B and class-D amplifiers for converting digital audio signals to analog signals is discussed. It is shown that the class-D amplifier is unsuitable due to distortion. Therefore a new principle involving a switch-mode power supply and a class-B amplifier is suggested. By regulating...... the supply voltage to the amplifier according to the amplitude of the audio signal, a higher efficiency than can be obtained by the usual principles is achieved. The regulation can be done very efficiently by generating the control signal to the power supply in advance of the audio signal, made possible...

  19. Area-Efficient 60 GHz +18.9 dBm Power Amplifier with On-Chip Four-Way Parallel Power Combiner in 65-nm CMOS

    Science.gov (United States)

    Farahabadi, Payam Masoumi; Basaligheh, Ali; Saffari, Parvaneh; Moez, Kambiz

    2017-02-01

    This paper presents a compact 60-GHz power amplifier utilizing a four-way on-chip parallel power combiner and splitter. The proposed topology provides the capability of combining the output power of four individual power amplifier cores in a compact die area. Each power amplifier core consists of a three-stage common-source amplifier with transformer-coupled impedance matching networks. Fabricated in 65-nm CMOS process, the measured gain of the 0.19-mm2 power amplifier at 60 GHz is 18.8 and 15 dB utilizing 1.4 and 1.0 V supply. Three-decibel band width of 4 GHz and P1dB of 16.9 dBm is measured while consuming 424 mW from a 1.4-V supply. A maximum saturated output power of 18.3 dBm is measured with the 15.9% peak power added efficiency at 60 GHz. The measured insertion loss is 1.9 dB at 60 GHz. The proposed power amplifier achieves the highest power density (power/area) compared to the reported 60-GHz CMOS power amplifiers in 65 nm or older CMOS technologies.

  20. Augmented twin-nonlinear two-box behavioral models for multicarrier LTE power amplifiers.

    Science.gov (United States)

    Hammi, Oualid

    2014-01-01

    A novel class of behavioral models is proposed for LTE-driven Doherty power amplifiers with strong memory effects. The proposed models, labeled augmented twin-nonlinear two-box models, are built by cascading a highly nonlinear memoryless function with a mildly nonlinear memory polynomial with cross terms. Experimental validation on gallium nitride based Doherty power amplifiers illustrates the accuracy enhancement and complexity reduction achieved by the proposed models. When strong memory effects are observed, the augmented twin-nonlinear two-box models can improve the normalized mean square error by up to 3 dB for the same number of coefficients when compared to state-of-the-art twin-nonlinear two-box models. Furthermore, the augmented twin-nonlinear two-box models lead to the same performance as previously reported twin-nonlinear two-box models while requiring up to 80% less coefficients.

  1. Wavelet network based predistortion method for wideband RF power amplifiers exhibiting memory effects

    Institute of Scientific and Technical Information of China (English)

    JIN Zhe; SONG Zhi-huan; HE Jia-ming

    2007-01-01

    RF power amplifiers (PAs) are usually considered as memoryless devices in most existing predistortion techniques.Nevertheless, in wideband communication systems, PA memory effects can no longer be ignored and memoryless predistortion cannot linearize PAs effectively. After analyzing PA memory effects, a novel predistortion method based on wavelet networks (WNs) is proposed to linearize wideband RF power amplifiers. A complex wavelet network with tapped delay lines is applied to construct the predistorter and then a complex backpropagation algorithm is developed to train the predistorter parameters. The simulation results show that compared with the previously published feed-forward neural network predistortion method, the proposed method provides faster convergence rate and better performance in reducing out-of-band spectral regrowth.

  2. High Power Amplifiers Chain nonlinearity influence on the accelerating beam stability in free electron laser (FLASH)

    CERN Document Server

    Cichalewski, w

    2010-01-01

    The high power amplifiers transfer characteristics nonlinearities can have a negative influence on the overall system performance. This is also true for the TESLA superconducting cavities accelerating field parameters control systems. This Low Level Radio Frequency control systems uses microwave high power amplifiers (like 10 MW klystrons) as actuators in the mentioned feedback loops. The amplitude compression and phase deviations phenomena introduced to the control signals can reduce the feedback performance and cause electron beam energy instabilities. The transfer characteristics deviations in the Free Electron Laser in Hamburg experiment have been investigated. The outcome of this study together with the description of the developed linearization method based on the digital predistortion approach have been described in this paper. Additionally, the results from the linearization tool performance tests in the FLASH's RF systems have been placed.

  3. Radar Waveform Pulse Analysis Measurement System for High-Power GaN Amplifiers

    Science.gov (United States)

    Thrivikraman, Tushar; Perkovic-Martin, Dragana; Jenabi, Masud; Hoffman, James

    2012-01-01

    This work presents a measurement system to characterize the pulsed response of high-power GaN amplifiers for use in space-based SAR platforms that require very strict amplitude and phase stability. The measurement system is able to record and analyze data on three different time scales: fast, slow, and long, which allows for greater detail of the mechanisms that impact amplitude and phase stability. The system is fully automated through MATLAB, which offers both instrument control capability and in-situ data processing. To validate this system, a high-power GaN HEMT amplifier operated in saturation was characterized. The fast time results show that variations to the amplitude and phase are correlated to DC supply transients, while long time characteristics are correlated to temperature changes.

  4. Augmented Twin-Nonlinear Two-Box Behavioral Models for Multicarrier LTE Power Amplifiers

    Directory of Open Access Journals (Sweden)

    Oualid Hammi

    2014-01-01

    Full Text Available A novel class of behavioral models is proposed for LTE-driven Doherty power amplifiers with strong memory effects. The proposed models, labeled augmented twin-nonlinear two-box models, are built by cascading a highly nonlinear memoryless function with a mildly nonlinear memory polynomial with cross terms. Experimental validation on gallium nitride based Doherty power amplifiers illustrates the accuracy enhancement and complexity reduction achieved by the proposed models. When strong memory effects are observed, the augmented twin-nonlinear two-box models can improve the normalized mean square error by up to 3 dB for the same number of coefficients when compared to state-of-the-art twin-nonlinear two-box models. Furthermore, the augmented twin-nonlinear two-box models lead to the same performance as previously reported twin-nonlinear two-box models while requiring up to 80% less coefficients.

  5. A Distributed Model of Four-Port Monolithic Transformer

    OpenAIRE

    Lee, Dong Ho; Ko, Sangsoo; Jeon, Sang-Hoon; Park, Jae-Woo; Hong, Songcheol

    2004-01-01

    This paper deals with modeling of a monolithic spiral transformer. The transformer is designed and fabricated as a symmetrical octagonal spiral structure using two-metal layer process on GaAs substrate for input balun applications of 2 GHz and 5 GHz push-pull power amplifiers. A distributed model of the transformer is developed to fit in wide frequency range with four ports. The model includes the skin effect which describes increase in series resistance with frequency. Six different se...

  6. High-power Yb-doped photonic bandgap fiber amplifier at 1150-1200 nm

    DEFF Research Database (Denmark)

    Shirakawa, A; Maruyama, H; Ueda, K

    2009-01-01

    Ytterbium-doped solid-core photonic bandgap fiber amplifiers operating at the long-wavelength edge of the ytterbium gain band are reported. The low-loss bandgap transmission window is formed in the very low gain region, whilst outside the bandgap, large attenuation inhibits the exponential growth...... knowledge, these are the highest output powers generating from active photonic bandgap fibers, as well as from ytterbium-doped fiber lasers at these wavelengths. (C) 2009 Optical Society of America...

  7. An efficient predistorter design for compensating nonlinear memory high power amplifier

    OpenAIRE

    2011-01-01

    This contribution applies digital predistorter to compensate distortions caused by memory high power amplifiers (HPAs) which exhibit true output saturation characteristics. Particle swarm optimization is first implemented to identify the Wiener HPA’s parameters. The estimated Wiener HPA model is then directly used to design the predistorter. The proposed digital predistorter solution is attractive owing to its low on-line computational complexity, small memory units required and simple VLSI h...

  8. A power supply error correction method for single-ended digital audio class D amplifiers

    Science.gov (United States)

    Yu, Zeqi; Wang, Fengqin; Fan, Yangyu

    2016-12-01

    In single-ended digital audio class D amplifiers (CDAs), the errors caused by power supply noise in the power stages degrade the output performance seriously. In this article, a novel power supply error correction method is proposed. This method introduces the power supply noise of the power stage into the digital signal processing block and builds a power supply error corrector between the interpolation filter and the uniform-sampling pulse width modulation (UPWM) lineariser to pre-correct the power supply error in the single-ended digital audio CDA. The theoretical analysis and implementation of the method are also presented. To verify the effectiveness of the method, a two-channel single-ended digital audio CDA with different power supply error correction methods is designed, simulated, implemented and tested. The simulation and test results obtained show that the method can greatly reduce the error caused by the power supply noise with low hardware cost, and that the CDA with the proposed method can achieve a total harmonic distortion + noise (THD + N) of 0.058% for a -3 dBFS, 1 kHz input when a 55 V linear unregulated direct current (DC) power supply (with the -51 dBFS, 100 Hz power supply noise) is used in the power stages.

  9. All-fiber 194 W single-frequency single-mode Yb-doped master-oscillator power-amplifier

    Science.gov (United States)

    Mermelstein, M. D.; Brar, K.; Andrejco, M. J.; Yablon, A. D.; Fishteyn, M.; Headley, C., III; DiGiovanni, D. J.

    2008-02-01

    A four-stage all-fiber single-frequency single-mode continuous-wave (cw) master-oscillator power-amplifier (MOPA) at 1083 nm is presented. Small mode area (SMA) and large mode area (LMA) amplifier stages are mode matched with a fiber mode converter (MC) and the signal and pumps are combined with tapered fiber bundles (TFBs). The final power stage uses a LMA Yb doped SBS-suppressing fiber. A single-frequency output power of 194 W is demonstrated with optical net and slope efficiencies of 73% and 80%, respectively. Numerical simulations for the signal output power and the SBS-induced Stokes backscattered power in the 4th stage amplifier agree with the experimental results. Pulse amplifier measurements showed a 400 W peak power output that was limited by the forward output ASE. The SBS reflectivity at 400 W output was only 2.75 x 10 -4.

  10. Design and analysis of a highly-integrated CMOS power amplifier for RFID readers

    Institute of Scientific and Technical Information of China (English)

    Gao Tongqiang; Zhang Chun; Chi Baoyong; Wang Zhihua

    2009-01-01

    To implement a fully-integrated on-chip CMOS power amplifier (PA) for RFID readers, the resonant frequency of each matching network is derived in detail. The highlight of the design is the adoption of a bonding wire as the output-stage inductor. Compared with the on-chip inductors in a CMOS process, the merit of the bondwire inductor is its high quality factor, leading to a higher output power and efficiency. The disadvantage of the bondwire inductor is that it is hard to control. A highly integrated class-E PA is implemented with 0.18-μm CMOS process. It can provide a maximum output power of 20 dBm and a 1 dB output power of 14.5 dBm. The maximum power-added efficiency (PAE) is 32.1%. Also, the spectral performance of the PA is analyzed for the specified RFID protocol.

  11. Design and analysis of a highly-integrated CMOS power amplifier for RFID readers

    Energy Technology Data Exchange (ETDEWEB)

    Gao Tongqiang [Department of Electronics, Tsinghua University, Beijing 100084 (China); Zhang Chun; Chi Baoyong; Wang Zhihua, E-mail: gtq03@mails.tsinghua.edu.c [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

    2009-06-01

    To implement a fully-integrated on-chip CMOS power amplifier (PA) for RFID readers, the resonant frequency of each matching network is derived in detail. The highlight of the design is the adoption of a bonding wire as the output-stage inductor. Compared with the on-chip inductors in a CMOS process, the merit of the bondwire inductor is its high quality factor, leading to a higher output power and efficiency. The disadvantage of the bondwire inductor is that it is hard to control. A highly integrated class-E PA is implemented with 0.18-mum CMOS process. It can provide a maximum output power of 20 dBm and a 1 dB output power of 14.5 dBm. The maximum power-added efficiency (PAE) is 32.1%. Also, the spectral performance of the PA is analyzed for the specified RFID protocol.

  12. Efficient power allocation for fixed-gain amplify-and-forward relaying in rayleigh fading

    KAUST Repository

    Zafar, Ammar

    2013-06-01

    In this paper, we study power allocation strategies for a fixed-gain amplify-and-forward relay network employing multiple relays. We consider two optimization problems for the relay network: 1) optimal power allocation to maximize the end-to-end signal-to-noise ratio (SNR) and 2) minimizing the total consumed power while maintaining the end-to-end SNR over a threshold value. We assume that the relays have knowledge of only the channel statistics of all the links. We show that the SNR maximization problem is concave and the power minimization problem is convex. Hence, we solve the problems through convex programming. Numerical results show the benefit of allocating power optimally rather than uniformly. © 2013 IEEE.

  13. Accurate geometry scalable complementary metal oxide semiconductor modelling of low-power 90 nm amplifier circuits

    Directory of Open Access Journals (Sweden)

    Apratim Roy

    2014-05-01

    Full Text Available This paper proposes a technique to accurately estimate radio frequency behaviour of low-power 90 nm amplifier circuits with geometry scalable discrete complementary metal oxide semiconductor (CMOS modelling. Rather than characterising individual elements, the scheme is able to predict gain, noise and reflection loss of low-noise amplifier (LNA architectures made with bias, active and passive components. It reduces number of model parameters by formulating dependent functions in symmetric distributed modelling and shows that simple fitting factors can account for extraneous (interconnect effects in LNA structure. Equivalent-circuit model equations based on physical structure and describing layout parasites are developed for major amplifier elements like metal–insulator–metal (MIM capacitor, spiral symmetric inductor, polysilicon (PS resistor and bulk RF transistor. The models are geometry scalable with respect to feature dimensions, i.e. MIM/PS width and length, outer-dimension/turns of planar inductor and channel-width/fingers of active device. Results obtained with the CMOS models are compared against measured literature data for two 1.2 V amplifier circuits where prediction accuracy for RF parameters (S(21, noise figure, S(11, S(22 lies within the range of 92–99%.

  14. Theoretical analysis of mode instability in high-power fiber amplifiers

    DEFF Research Database (Denmark)

    Hansen, Kristian Rymann; Alkeskjold, Thomas Tanggaard; Broeng, Jes;

    2013-01-01

    We present a simple theoretical model of transverse mode instability in high-power rare-earth doped fiber amplifiers. The model shows that efficient power transfer between the fundamental and higher-order modes of the fiber can be induced by a nonlinear interaction mediated through the thermo......-optic effect, leading to transverse mode instability. The temporal and spectral characteristics of the instability dynamics are investigated, and it is shown that the instability can be seeded by both quantum noise and signal intensity noise, while pure phase noise of the signal does not induce instability...

  15. The Design and Life Test of a Multifunction Power Amplifier for Space Application

    Directory of Open Access Journals (Sweden)

    Xiuqin Xu

    2016-01-01

    Full Text Available A new multifunction power amplifier (MFPA is designed and fabricated for the application of point-to-point K-Band backhaul TR module. A DC temperature life test was performed to model the up-limit temperature effect of the designed MFPA under space application. After 240 hours of 100°C life test, the test results illustrate that the designed MFPA has only slight power degradation at the saturation region without change of the linear gain. The general performance of the designed MFPA satisfies the requirement of the application scenario.

  16. Spectral Analysis of Polynomial Nonlinearity with Applications to RF Power Amplifiers

    Directory of Open Access Journals (Sweden)

    G. Tong Zhou

    2004-09-01

    Full Text Available The majority of the nonlinearity in a communication system is attributed to the power amplifier (PA present at the final stage of the transmitter chain. In this paper, we consider Gaussian distributed input signals (such as OFDM, and PAs that can be modeled by memoryless or memory polynomials. We derive closed-form expressions of the PA output power spectral density, for an arbitrary nonlinear order, based on the so-called Leonov-Shiryaev formula. We then apply these results to answer practical questions such as the contribution of AM/PM conversion to spectral regrowth and the relationship between memory effects and spectral asymmetry.

  17. Vacuum Testing of a Miniaturized Switch Mode Amplifier Powering an Electrothermal Plasma Micro-Thruster

    Directory of Open Access Journals (Sweden)

    Christine Charles

    2017-08-01

    Full Text Available A structurally supportive miniaturized low-weight (≤150 g radiofrequency switch mode amplifier developed to power the small diameter Pocket Rocket electrothermal plasma micro-thruster called MiniPR is tested in vacuum conditions representative of space to demonstrate its suitability for use on nano-satellites such as “CubeSats.” Argon plasma characterization is carried out by measuring the optical emission signal seen through the plenum window vs. frequency (12.8–13.8 MHz and the plenum cavity pressure increase (indicative of thrust generation from volumetric gas heating in the plasma cavity vs. power (1–15 Watts with the amplifier operating at atmospheric pressure and a constant flow rate of 20 sccm. Vacuum testing is subsequently performed by measuring the operational frequency range of the amplifier as a function of gas flow rate. The switch mode amplifier design is finely tuned to the input impedance of the thruster (~16 pF to provide a power efficiency of 88% at the resonant frequency and a direct feed to a low-loss (~10 % impedance matching network. This system provides successful plasma coupling at 1.54 Watts for all investigated flow rates (10–130 sccm for cryogenic pumping speeds of the order of 6,000 l.s−1 and a vacuum pressure of the order of ~2 × 10−5 Torr during operation. Interestingly, the frequency bandwidth for which a plasma can be coupled increases from 0.04 to 0.4 MHz when the gas flow rate is increased, probably as a result of changes in the plasma impedance.

  18. Econophysics of adaptive power markets: When a market does not dampen fluctuations but amplifies them.

    Science.gov (United States)

    Krause, Sebastian M; Börries, Stefan; Bornholdt, Stefan

    2015-07-01

    The average economic agent is often used to model the dynamics of simple markets, based on the assumption that the dynamics of a system of many agents can be averaged over in time and space. A popular idea that is based on this seemingly intuitive notion is to dampen electric power fluctuations from fluctuating sources (as, e.g., wind or solar) via a market mechanism, namely by variable power prices that adapt demand to supply. The standard model of an average economic agent predicts that fluctuations are reduced by such an adaptive pricing mechanism. However, the underlying assumption that the actions of all agents average out on the time axis is not always true in a market of many agents. We numerically study an econophysics agent model of an adaptive power market that does not assume averaging a priori. We find that when agents are exposed to source noise via correlated price fluctuations (as adaptive pricing schemes suggest), the market may amplify those fluctuations. In particular, small price changes may translate to large load fluctuations through catastrophic consumer synchronization. As a result, an adaptive power market may cause the opposite effect than intended: Power demand fluctuations are not dampened but amplified instead.

  19. Investigation of Energy Consumption and Sound Quality for Class-D Audio Amplifiers using Tracking Power Supplies

    DEFF Research Database (Denmark)

    Yamauchi, Akira; Schneider, Henrik; Knott, Arnold;

    2015-01-01

    The main advantage of Class-D audio amplifiers is high efficiency which is often stated to be more than 90 % but at idle or low power levels the efficiency is much lower. The waste energy is an environmental concern, a concern in mobile applications where long battery operation is required...... power supply tracking and its influence on power losses, audio performance and environmental impact for a 130 W class-D amplifier prototype as well as a commercialized class-D amplifier. Both modeled and experimental results verify that a large improvement of efficiency can be achieved. The total...

  20. High Power and Efficiency Space Traveling-Wave Tube Amplifiers With Reduced Size and Mass for NASA Missions

    Science.gov (United States)

    Simons, Rainee N.; Wilson, Jeffrey D.; Force, Dale A.

    2008-01-01

    Recent advances in high power and efficiency space traveling-wave tube amplifiers (TWTAs) for NASA s space-to-Earth communications are presented in this paper. The RF power and efficiency of a new K-Band amplifier are 40 W and 50 percent and that of a new Ka-Band amplifier are 200 W and 60 percent. An important figure-of-merit, which is defined as the ratio of the RF power output to the mass (W/kg) of a TWT has improved by a factor of ten over the previous generation Ka-Band devices.

  1. 175-W continuous-wave master oscillator power amplifier structure ytterbium-doped all-fiber laser

    Institute of Scientific and Technical Information of China (English)

    Ping Yan; Shupeng Yin; Mali Gong

    2008-01-01

    We report on hundred watts range ytterbium-doped all-fiber laser assembly based on the master oscillator power amplifier structure. It consisted of an oscillator and an amplifier with all-fiber components. And fiber fusion splice made the laser be an integrated fiber system. It generated up to 175.5 W of continuouswave (CW) output power at 1085 nm with more than 75% extraction efficiency in the amplifier when the total coupled pump power into the double clad fiber was 270 W.

  2. High-Power Amplifier Compatible Internally Sensed Optical Phased Array for Space Debris Tracking and Maneuvering

    Science.gov (United States)

    Roberts, L.; Francis, S.; Sibley, P.; Ward, R.; Smith, C.; McClelland, D.; Shaddock, D.

    2016-09-01

    Optical phased arrays (OPAs) provide a way to scale optical power beyond the capabilities of conventional CW lasers via coherent beam combination. By stabilising the relative output phase of multiple spatially separate lasers, OPAs form a coherent optical wavefront in the far field. Since the phase of each laser can be controlled independently, OPAs also have the ability to manipulate the distribution of optical power in the far field, and therefore may provide the capability to compensate for atmospheric turbulence. Combined with their inherent scalability and high power handling capabilities, OPAs are a promising technology for CW space debris ranging and manoeuvring. The OPA presented here is unique in its ability to sense the phase of each laser internally, without requiring any external sampling optics between it and the telescope. This allows the internally sensed OPA to be constructed entirely within fibre, utilising high-power fiber amplifiers to scale optical power beyond the limits of any conventional single lasers. The total power that can be delivered by each emitter in the OPA is limited only by the onset of stimulated Brillouin scattering, a non-linear effect that clamps the amount of power that can be delivered through a fiber waveguide. A three element internally sensed OPA developed at the Australian National University has been demonstrated to coherently combine three commercial 15 Watt fiber amplifiers with an output phase stability of one 200th of a wavelength. We have also demonstrated the ability to dynamically manipulate the distribution of optical power in the far-field at a bandwidth of up to 10 kHz. Since the OPA's control system is implemented using field-programmable gate-array technology, the system may be scaled beyond 100 emitters, potentially reaching the kilowatt level optical powers required to perturb the orbit of space debris.

  3. A highly linear fully integrated CMOS power amplifier with an analog predistortion technique

    Energy Technology Data Exchange (ETDEWEB)

    Jin Boshi; Li Lewei; Wu Qun; Yang Guohui; Zhang Kuang, E-mail: boshijin@rdamicro.com [Department of Electronic and Communications Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2011-05-15

    A transformer-based CMOS power amplifier (PA) is linearized using an analog predistortion technique for a 2.5-GHz m-WiMAX transmitter. The third harmonic of the power stage and driver stage can be cancelled out in a specific power region. The two-stage PA fabricated in a standard 0.18-{mu}m CMOS process delivers 27.5 dBm with 27% PAE at the 1-dB compression point (P{sub 1dB}) and offers 21 dB gain. The PA achieves 5.5 % EVM and meets the spectrum mask at 20.5 dBm average power. Another conventional PA with a zero-cross-point of g{sub m3} bias is also fabricated and compared to prove its good linearity and efficiency. (semiconductor devices)

  4. Design of an Adaptive Predistorter for Solid State Power Amplifier in Wireless OFDM Systems

    Directory of Open Access Journals (Sweden)

    Rui J. P. de Figueiredo

    2009-01-01

    Full Text Available Orthogonal frequency division multiplexing (OFDM is a powerful modulation choice for wideband wireless communication systems. However, its high peak-to-average power ratio greatly limits the high power amplifier (HPA power efficiency. Here, we present the design of an adaptive predistorter to compensate the distortion caused by the HPA. Specifically, we deal with the implementation issue of the proposed predistorter in Lee and de Figueiredo's work (2006. The performance improvement by predistorter is verified by both floating-point simulation and fixed-point simulation, where the latter includes the distortion effects from the hardware. The bit widths for OFDM signals, ADC, and DAC are evaluated, and the bit width of 10 is shown to be sufficient for the hardware design.

  5. Design and modeling of InP DHBT power amplifiers at millimeter-wave frequencies

    DEFF Research Database (Denmark)

    Yan, Lei; Johansen, Tom K.

    2012-01-01

    In this paper, the design and modeling of InP DHBT based millimeter-wave(mm-wave) power amplifiers is described. This includes the modeling of InP DHBT devices and layout parasitics. An EM-circuit co-simulation approach is described to allow all parasitics to be modeled for accurate circuit...... performance evaluation. A single-branch cascode based PA using single-finger InP DHBT devices shows a measured power gain of 9.2dB and a saturated output power of 12.3dBm at 67.2GHz. The output power at 1dB compression is 9.0dBm. A similar two-way combined cascode based PA using three-finger devices...

  6. High-Power and Low-Noise 10-GHz All-Active Monolithic Mode-Locked Lasers with Surface Etched Bragg Grating

    OpenAIRE

    Larsson, David; Yvind, Kresten; Hvam, Jørn Märcher

    2007-01-01

    We have fabricated 4.4 mm long monolithic InAlGaAsP/InP mode-locked lasers with integrated deeply surface etched DBR-mirrors. The lasers produce 3.7 ps transform-limited Gaussian pulses with 10 mW average power and 250 fs timing jitter.

  7. High power 352 MHz solid state amplifiers developed at the Synchrotron SOLEIL

    Directory of Open Access Journals (Sweden)

    P. Marchand

    2007-11-01

    Full Text Available In SOLEIL, 5 solid state amplifiers provide the required rf power at 352  MHz: 1×35  kW in the booster and 4×190  kW in the storage ring. They consist in a combination of a large number of 330 W elementary modules (1×147 in the booster and 4×724 in the storage ring, based on a design developed in-house, with MOSFETs (metal-oxide-semiconductor field-effect transistors, integrated circulators, and individual power supplies. Although quite innovative and challenging for the required power range, this technology is very attractive and presents significant advantages as compared to the more conventional vacuum tubes, klystrons, or inductive output tubes (IOTs. The booster and two of the storage ring power plants have been successfully commissioned and the first operational experience is quite satisfactory. The amplifiers proved to be very reliable as well as easy and flexible in operation; they have not been responsible for any beam time loss.

  8. Materials physics and device development for improved efficiency of GaN HEMT high power amplifiers.

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Steven Ross; Follstaedt, David Martin; Wright, Alan Francis; Baca, Albert G.; Briggs, Ronald D.; Provencio, Paula Polyak; Missert, Nancy A.; Allerman, Andrew Alan; Marsh, Phil F.; Koleske, Daniel David; Lee, Stephen Roger; Shul, Randy John; Seager, Carleton Hoover; Tigges, Christopher P.

    2005-12-01

    GaN-based microwave power amplifiers have been identified as critical components in Sandia's next generation micro-Synthetic-Aperture-Radar (SAR) operating at X-band and Ku-band (10-18 GHz). To miniaturize SAR, GaN-based amplifiers are necessary to replace bulky traveling wave tubes. Specifically, for micro-SAR development, highly reliable GaN high electron mobility transistors (HEMTs), which have delivered a factor of 10 times improvement in power performance compared to GaAs, need to be developed. Despite the great promise of GaN HEMTs, problems associated with nitride materials growth currently limit gain, linearity, power-added-efficiency, reproducibility, and reliability. These material quality issues are primarily due to heteroepitaxial growth of GaN on lattice mismatched substrates. Because SiC provides the best lattice match and thermal conductivity, SiC is currently the substrate of choice for GaN-based microwave amplifiers. Obviously for GaN-based HEMTs to fully realize their tremendous promise, several challenges related to GaN heteroepitaxy on SiC must be solved. For this LDRD, we conducted a concerted effort to resolve materials issues through in-depth research on GaN/AlGaN growth on SiC. Repeatable growth processes were developed which enabled basic studies of these device layers as well as full fabrication of microwave amplifiers. Detailed studies of the GaN and AlGaN growth of SiC were conducted and techniques to measure the structural and electrical properties of the layers were developed. Problems that limit device performance were investigated, including electron traps, dislocations, the quality of semi-insulating GaN, the GaN/AlGaN interface roughness, and surface pinning of the AlGaN gate. Surface charge was reduced by developing silicon nitride passivation. Constant feedback between material properties, physical understanding, and device performance enabled rapid progress which eventually led to the successful fabrication of state of the

  9. An on-chip temperature compensation circuit for an InGaP/GaAs HBT RF power amplifier

    Science.gov (United States)

    Chengzhan, Li; Zhijian, Chen; Jiwei, Huang; Yongping, Wang; Chuanhui, Ma; Hanbing, Yang; Yinghao, Liao; Yong, Zhou; Bin, Liu

    2011-03-01

    A new on-chip temperature compensation circuit for a GaAs-based HBT RF amplifier applied to wireless communication is presented. The simple compensation circuit is composed of one GaAs HBT and five resistors with various values, which allow the power amplifier to achieve better thermal characteristics with a little degradation in performance. It effectively compensates for the temperature variation of the gain and the output power of the power amplifier by regulating the base quiescent bias current. The temperature compensation circuit is applied to a 3-stage integrated power amplifier for wireless communication applications, which results in an improvement in the gain variation from 4.0 to 1.1 dB in the temperature range between -20 and +80 °C.

  10. An on-chip temperature compensation circuit for an InGaP/GaAs HBT RF power amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Li Chengzhan; Chen Zhijian; Huang Jiwei; Wang Yongping; Ma Chuanhui; Yang Hanbing; Liao Yinghao; Zhou Yong; Liu Bin, E-mail: lichzh@runxinic.com [Guangzhou Runxin Information Technology Co., Ltd, Guangzhou 510663 (China)

    2011-03-15

    A new on-chip temperature compensation circuit for a GaAs-based HBT RF amplifier applied to wireless communication is presented. The simple compensation circuit is composed of one GaAs HBT and five resistors with various values, which allow the power amplifier to achieve better thermal characteristics with a little degradation in performance. It effectively compensates for the temperature variation of the gain and the output power of the power amplifier by regulating the base quiescent bias current. The temperature compensation circuit is applied to a 3-stage integrated power amplifier for wireless communication applications, which results in an improvement in the gain variation from 4.0 to 1.1 dB in the temperature range between -20 and +80 {sup 0}C. (semiconductor integrated circuits)

  11. An on-chip temperature compensation circuit for an InGaP/GaAs HBT RF power amplifier

    Institute of Scientific and Technical Information of China (English)

    Li Chengzhan; Chen Zhijian; Huang Jiwei; Wang Yongping; Ma Chuanhui; Yang Hanbing; Liao Yinghao; Zhou Yong; Liu Bin

    2011-01-01

    A new on-chip temperature compensation circuit for a GaAs-based HBT RF amplifier applied to wireless communication is presented.The simple compensation circuit is composed of one GaAs HBT and five resistors with various values,which allow the power amplifier to achieve better thermal characteristics with a little degradation in performance.It effectively compensates for the temperature variation of the gain and the output power of the power amplifier by regulating the base quiescent bias current.The temperature compensation circuit is applied to a 3-stage integrated power amplifier for wireless communication applications,which results in an improvement in the gain variation from 4.0 to 1.1 dB in the temperature range between -20 and +80 ℃.

  12. High-Efficiency, Ka-band Solid-State Power Amplifier Utilizing GaN Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop an efficient, solid-state power amplifier (SSPA), operating at Ka-band frequencies, for high data rate, long range space...

  13. Robust Power Allocation for Multi-Carrier Amplify-and-Forward Relaying Systems

    KAUST Repository

    Rao, Anlei

    2012-09-08

    It has been shown that adaptive power allocation can provide a substantial performance gain in wireless communication systems when perfect channel state information (CSI) is available at the transmitter. However when only imperfect CSI is available, the performance may degrade significantly, and as such robust power allocation schemes have been developed to minimize the effects of this degradation. In this paper, we investigate power allocation strategies for multicarrier systems, in which each subcarrier employs single amplify-and-forward (AF) relaying scheme. Optimal power allocation schemes are proposed by maximizing the approximated channel capacity under aggregate power constraint (APC) and separate power constraint (SPC). By comparison with the uniform power allocation scheme and the best channel power allocation scheme, we confirm that both the APC and SPC schemes achieve a performance gain over benchmark schemes. In addition, the impact of channel uncertainty is also considered in this paper by modeling the uncertainty regions as bounded sets, and results show that the uncertainty can degrade the worst-case performance significantly.

  14. Robust Power Allocation for Multi-Carrier Amplify-and-Forward Relaying Systems

    KAUST Repository

    Rao, Anlei

    2012-09-08

    It has been shown that adaptive power allocation can provide a substantial performance gain in wireless communication systems when perfect channel state information (CSI) is available at the transmitter. However when only imperfect CSI is available, the performance may degrade significantly, and as such robust power allocation schemes have been developed to minimize the effects of this degradation. In this paper, we investigate power allocation strategies for multicarrier systems, in which each subcarrier employs single amplify-and-forward (AF) relaying scheme. Optimal power allocation schemes are proposed by maximizing the approximated channel capacity under aggregate power constraint (APC) and separate power constraint (SPC). By comparison with the uniform power allocation scheme and the best channel power allocation scheme, we confirm that both the APC and SPC schemes achieve a performance gain over benchmark schemes. In addition, the impact of channel uncertainty is also considered in this paper by modeling the uncertainty regions as bounded sets, and results show that the uncertainty can degrade the worst- case performance significantly.

  15. 1.38 W tunable high-power narrow-linewidth external-cavity tapered amplifier at 670 nm

    DEFF Research Database (Denmark)

    Chi, Mingjun; Erbert, G.; Sumpf, B.;

    2010-01-01

    A diffraction-limited narrow-linewidth diode laser system based on a tapered amplifier in external cavity is demonstrated. 1.38 W output power is obtained. The laser system is tunable from 659 to 675 nm.......A diffraction-limited narrow-linewidth diode laser system based on a tapered amplifier in external cavity is demonstrated. 1.38 W output power is obtained. The laser system is tunable from 659 to 675 nm....

  16. A Unified Distortion Analysis of Nonlinear Power Amplifiers with Memory Effects for OFDM Signals

    Science.gov (United States)

    Zhang, Yitao; Araki, Kiyomichi

    Nonlinear distortions in power amplifiers (PAs) generate spectral regrowth at the output, which causes interference to adjacent channels and errors in digitally modulated signals. This paper presents a novel method to evaluate adjacent channel leakage power ratio (ACPR) and error vector magnitude (EVM) from the amplitude-to-amplitude (AM/AM) and amplitude-to-phase (AM/PM) characteristics. The transmitted signal is considered to be complex Gaussian distributed in orthogonal frequency-division multiplexing (OFDM) systems. We use the Mehler formula to derive closed-form expressions of the PAs output power spectral density (PSD), ACPR and EVM for memoryless PA and memory PA respectively. We inspect the derived relationships using an OFDM signal in the IEEE 802.11a WLAN standard. Simulation results show that the proposed method is appropriate to predict the ACPR and EVM values of the nonlinear PA output in OFDM systems, when the AM/AM and AM/PM characteristics are known.

  17. Study of a high power sine waveguide traveling wave tube amplifier centered at 8 GHz

    Science.gov (United States)

    Hoff, Brad W.; Simon, David S.; French, David M.; Lau, Y. Y.; Wong, Patrick

    2016-10-01

    Performance of a 20-stage X-band sine waveguide amplifier, driven by a 40 A, 100 kV, cylindrical electron beam, is studied using numerical simulation and interpreted using Pierce's classical traveling wave tube theory. For an input signal power level of 1.8 kW, particle-in-cell simulations predict gain and bandwidth values exceeding 14 dB and 13%, respectively. For an input signal power level of 7.2 kW, particle-in-cell simulations predict gain and bandwidth values exceeding 12 dB and 15%, respectively, with output power levels exceeding 110 kW at peak gain. Also given are: an assessment of the space charge factor (Pierce's QC parameter) for the complex circuit using simulation data, and an evaluation of the harmonic contents in the beam current.

  18. Cryogenic operation of a 24 GHz MMIC SiGe HBT medium power amplifier

    Science.gov (United States)

    Qin, Guoxuan; Jiang, Ningyue; Seo, Jung-Hun; Cho, Namki; Ponchak, George E.; van der Weide, Daniel; Ma, Pingxi; Stetson, Scott; Racanelli, Marco; Ma, Zhenqiang

    2010-12-01

    The performance of a SiGe heterojunction bipolar transistor (HBT) millimetre-wave power amplifier (PA) operating at cryogenic temperature was reported and analysed for the first time. A 24 GHz two-stage medium PA employing common-emitter and common-base SiGe power HBTs in the first and the second stage, respectively, showed a significant power gain increase at 77 K in comparison with that measured at room temperature. Detailed analyses indicate that cryogenic operation of SiGe HBT-based PAs mainly affects (improves) the performance of the SiGe HBTs in the circuits due to transconductance enhancement through magnified, favourable changes of SiGe bandgap due to cooling (ΔEg/kT) and minimized thermal effects, with little influence on the passive components of the circuits.

  19. Simultaneous Wireless Information and Power Transfer for MIMO Amplify-and-Forward Relay Systems

    KAUST Repository

    Benkhelifa, Fatma

    2016-01-06

    In this paper, we investigate the simultaneous wireless information and power transfer (SWIPT) for the two-hop Multiple-Input Multiple-Output (MIMO) Amplify-and-Forward (AF) relay communication systems with the multiantenna energy harvesting relay. We derive the optimal source and relay covariance matrices to characterize the achievable region between the sourcedestination rate and the harvested energy at the relay, namely Rate-Energy (R-E) region. In this context, we consider the ideal scenario where the energy harvester (EH) receiver and the information decoder (ID) receiver at the relay can simultaneously decode the information and harvest the energy at the relay. Then, we consider more practical schemes which are the power splitting (PS) and the time switching (TS) which separate the EH and ID transfer over the power domain and the time domain, respectively.

  20. A fully integrated 3.5 GHz CMOS differential power amplifier driver

    Science.gov (United States)

    Xiaodong, Xu; Haigang, Yang; Tongqiang, Gao; Hongfeng, Zhang

    2013-07-01

    A fully integrated CMOS differential power amplifier driver (PAD) is proposed for WiMAX applications. In order to fulfill the differential application requirements, a transmission line transformer is used as the output matching network. A differential inductance constitutes an inter-stage matching network. Meanwhile, an on chip balun realizes input matching as well as single-end to differential conversion. The PAD is fabricated in a 0.13 μm RFCMOS process. The chip size is 1.1 × 1.1 mm2 with all of the matching network integrated on chip. The saturated power is around 10 dBm and power gain is about 12 dB.

  1. First On-Wafer Power Characterization of MMIC Amplifiers at Sub-Millimeter Wave Frequencies

    Science.gov (United States)

    Fung, A. K.; Gaier, T.; Samoska, L.; Deal, W. R.; Radisic, V.; Mei, X. B.; Yoshida, W.; Liu, P. S.; Uyeda, J.; Barsky, M.; Lai, R.

    2008-01-01

    Recent developments in semiconductor technology have enabled advanced submillimeter wave (300 GHz) transistors and circuits. These new high speed components have required new test methods to be developed for characterizing performance, and to provide data for device modeling to improve designs. Current efforts in progressing high frequency testing have resulted in on-wafer-parameter measurements up to approximately 340 GHz and swept frequency vector network analyzer waveguide measurements to 508 GHz. On-wafer noise figure measurements in the 270-340 GHz band have been demonstrated. In this letter we report on on-wafer power measurements at 330 GHz of a three stage amplifier that resulted in a maximum measured output power of 1.78mW and maximum gain of 7.1 dB. The method utilized demonstrates the extension of traditional power measurement techniques to submillimeter wave frequencies, and is suitable for automated testing without packaging for production screening of submillimeter wave circuits.

  2. Influence of core NA on Thermal-Induced Mode Instabilities in High Power Fiber Amplifiers

    CERN Document Server

    Tao, Rumao; Wang, Xiaolin; Zhou, Pu; Liu, Zejin

    2015-01-01

    We report on the influence of core NA on thermal-induced mode instabilities (MI) in high power fiber amplifiers. Influence of core NA and V-parameter on MI has been investigated numerically. It shows that core NA has larger influence on MI for fibers with smaller core-cladding-ratio, and the influence of core NA on threshold is more obvious when the amplifiers are pumped at 915nm. The dependence of threshold on V-parameter revealed that the threshold increases linearly as V-parameter decreases when V-parameter is larger than 3.5, and the threshold shows exponentially increase as V-parameter decreases when V-parameter is less than 3.5. We also discussed the effect of linewidth on MI, which indicates that the influence of linewidth can be neglected for linewidth smaller than 1nm when the fiber core NA is smaller than 0.07 and fiber length is shorter than 20m. Fiber amplifiers with different core NA were experimentally analyzed, which agreed with the theoretical predictions.

  3. Muscle trade-offs in a power-amplified prey capture system.

    Science.gov (United States)

    Blanco, M Mendoza; Patek, S N

    2014-05-01

    Should animals operating at great speeds and accelerations use fast or slow muscles? The answer hinges on a fundamental trade-off: muscles can be maximally fast or forceful, but not both. Direct lever systems offer a straightforward manifestation of this trade-off, yet the fastest organisms use power amplification, not direct lever action. Power-amplified systems typically use slow, forceful muscles to preload springs, which then rapidly release elastic potential energy to generate high speeds and accelerations. However, a fast response to a stimulus may necessitate fast spring-loading. Across 22 mantis shrimp species (Stomatopoda), this study examined how muscle anatomy correlates with spring mechanics and appendage type. We found that muscle force is maximized through physiological cross-sectional area, but not through sarcomere length. Sit-and-wait predators (spearers) had the shortest sarcomere lengths (fastest contractions) and the slowest strike speeds. The species that crush shells (smashers) had the fastest speeds, most forceful springs, and longest sarcomeres. The origin of the smasher clade yielded dazzlingly high accelerations, perhaps due to the release from fast spring-loading for evasive prey capture. This study offers a new window into the dynamics of force-speed trade-offs in muscles in the biomechanical, comparative evolutionary framework of power-amplified systems. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  4. An ultra-low-power pulse oximeter implemented with an energy-efficient transimpedance amplifier.

    Science.gov (United States)

    Tavakoli, M; Turicchia, L; Sarpeshkar, R

    2010-02-01

    Pulse oximeters are ubiquitous in modern medicine to noninvasively measure the percentage of oxygenated hemoglobin in a patient's blood by comparing the transmission characteristics of red and infrared light-emitting diode light through the patient's finger with a photoreceptor. We present an analog single-chip pulse oximeter with 4.8-mW total power dissipation, which is an order of magnitude below our measurements on commercial implementations. The majority of this power reduction is due to the use of a novel logarithmic transimpedance amplifier with inherent contrast sensitivity, distributed amplification, unilateralization, and automatic loop gain control. The transimpedance amplifier, together with a photodiode current source, form a high-performance photoreceptor with characteristics similar to those found in nature, which allows LED power to be reduced. Therefore, our oximeter is well suited for portable medical applications, such as continuous home-care monitoring for elderly or chronic patients, emergency patient transport, remote soldier monitoring, and wireless medical sensing. Furthermore, our design obviates the need for an A-to-D and digital signal processor and leads to a small single-chip solution. We outline how extensions of our work could lead to submilliwatt oximeters.

  5. Multiple Differential-Amplifier MMICs Embedded in Waveguides

    Science.gov (United States)

    Kangaslahti, Pekka; Schlecht, Erich

    2010-01-01

    Compact amplifier assemblies of a type now being developed for operation at frequencies of hundreds of gigahertz comprise multiple amplifier units in parallel arrangements to increase power and/or cascade arrangements to increase gains. Each amplifier unit is a monolithic microwave integrated circuit (MMIC) implementation of a pair of amplifiers in differential (in contradistinction to single-ended) configuration. Heretofore, in cascading amplifiers to increase gain, it has been common practice to interconnect the amplifiers by use of wires and/or thin films on substrates. This practice has not yielded satisfactory results at frequencies greater than 200 Hz, in each case, for either or both of two reasons: Wire bonds introduce large discontinuities. Because the interconnections are typically tens of wavelengths long, any impedance mismatches give rise to ripples in the gain-vs.-frequency response, which degrade the performance of the cascade.

  6. Optical Fiber Pumped High Repetition Rate and High Power Nd:YVO4 Picosecond Regenerative Amplifier

    Directory of Open Access Journals (Sweden)

    Zhen-Ao Bai

    2015-08-01

    Full Text Available We report a stable optical fiber pumped Nd:YVO4 all solid state regenerative amplifier with all fiber picosecond laser as seed source. 888 nm Yb optical fiber lasers was chosen as pump source to reduce quantum defect for improved thermal performance. At the repetition rate of 99.6 kHz, maximum power of 19.63 W with 36 ps pulse duration were achieved when seeded by a 150 mW picosecond oscillator. The wavelength delivered was 1064.07 nm with spectral width of 0.14 nm.

  7. An audio FIR-DAC in a BCD process for high power Class-D amplifiers

    OpenAIRE

    Doorn, T.S.; Tuijl, van, B.A.J.; Schinkel, D.; Annema, A.J.; Berkhout, M.; Nauta, B.

    2005-01-01

    A 322 coefficient semi-digital FIR-DAC using a 1-bit PWM input signal was designed and implemented in a high voltage, audio power bipolar CMOS DMOS (BCD) process. This facilitates digital input signals for an analog class-D amplifier in BCD. The FIR-DAC performance depends on the ISI-resistant nature of this PWM-signal. An impulse response with only positive coefficients was chosen, because of its resistance to deadzone and mismatch. With a DAC current of 0.5 mA, the dynamic range is 111 dB (...

  8. Impact of Nonlinear Power Amplifier on Link Adaptation Algorithm of OFDM Systems

    DEFF Research Database (Denmark)

    Das, Suvra S.; Tariq, Faisal; Rahman, Muhammad Imadur

    2007-01-01

    The impact of non linear distortion due to High Power Amplifier (HPA) on the performance of Link Adaptation (LA) - Orthogonal Frequency Division Multiplexing (OFDM) based wireless system is analyzed. The performance of both Forward Error Control Coding (FEC) en-coded and uncoded system is evaluated....... LA maximizes the throughput while maintaining a required Block Error Rate (BLER). It is found that when OFDM signal, which has high PAPR, suffers non linear distortion due to non ideal HPA, the LA fails to meet the target BLER. Detailed analysis of the distortion and effects on LA are presented...

  9. A novel broadband power amplifier in SiGe HBT technology

    Institute of Scientific and Technical Information of China (English)

    Li Wenyuan; Zhang Qian

    2013-01-01

    A novel broadband power amplifier fabricated in 0.13 μm SiGe HBT technology is realized.The pseudo-differential structure is proposed to avoid the influence of the bonding wire due to the AC virtual ground created at the common emitter node.A compensated matching technique is adopted in interstage matching to expand bandwidth.A multi-stage broadband matching technique is used in an input/output matching network to offer broadband impedance matching,which ensures maximum power transfer.An adaptive bias circuit could improve linearity and efficiency in wide output power level.With 2.5 V power supply,the measured results achieve 96% 3-dB bandwidth (517-1470 MHz),27.2 dB power gain,26.9 dBm maximum output power,19.7 dBm output 1 dB compression point,and 26.7% power added efficiency.

  10. High Power Er/Yb Codoped Double Clad Fiber Pulsed Amplifier Based on an All-Fiber Configuration

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lei; NING Ji-Ping; CHEN Cheng; HAN Qun; ZHANG Wei-Yi; WANG Jun-Tao

    2009-01-01

    We report an all-fiber two-stage high power pulsed amplifier,seeded with a 1550nm,1 kHz repetition rate rectangular pulse,and based on Er/Yb co-doped double clad fiber.All the characteristics are measured in the experiment.The maxima/slope efficiency is 22.56%,which is the highest we know of at such a low repetition rate,and the maximal output signal power is 1W.The various factors that affect the pulsed amplifier performance are analyzed.A high output power while keeping high power conversion efficiency can be obtained with careful selection of the input power,pump power and repetition rate.The experimental results show that the crucial parameters should be optimized when designing all-fiber pulsed amplifiers.

  11. High power, continuous-wave, single frequency fiber amplifier at 1091 nm and frequency doubling to 545.5 nm

    CERN Document Server

    Stappel, M; Kolbe, D; Walz, J

    2012-01-01

    We present a high power single-frequency ytterbium fiber amplifier system with an output power of 30 W at 1091 nm. The amplifier system consists of two stages, a preamplifier stage in which amplified spontaneous emission is efficiently suppressed (>40 dB) and a high power amplifier with an efficiency of 52 %. Two different approaches of frequency doubling are compared. We achieve 8.6 W at 545.5 nm by single-pass frequency doubling in a MgO-doped periodically poled stoichiometric LiTaO3 and up to 19.3 W at 545.5 nm by frequency doubling with a lithium-triborate (LBO) crystal in an external enhancement cavity.

  12. MW peak power Er/Yb-doped fiber femtosecond laser amplifier at 1.5 µm center wavelength

    Science.gov (United States)

    Han, Seongheum; Jang, Heesuk; Kim, Seungman; Kim, Young-Jin; Kim, Seung-Woo

    2017-08-01

    An erbium (Er)/ytterbium (Yb) co-doped double-clad fiber is configured to amplify single-mode pulses with a high average power of 10 W at a 1.5 µm center wavelength. The pulse duration at the exit of the Er/Yb fiber amplifier is measured to be ~440 fs after grating-based compression. The whole single-mode operation of the amplifier system permits the M 2-value of the output beam quality to be evaluated better than 1.05. By tuning the repetition rate from 100 MHz down to 600 kHz, the pulse peak power is scaled up to 19.1 MW to be the highest ever reported using an Er/Yb single-mode fiber. The proposed amplifier system is well suited for strong-power applications such as free-space LIDAR, non-thermal machining and medical surgery.

  13. Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2008-01-01

    An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...

  14. Bioaffinity chromatography on monolithic supports

    NARCIS (Netherlands)

    Tetala, K.K.R.; Beek, van T.A.

    2010-01-01

    Affinity chromatography on monolithic supports is a powerful analytical chemical platform because it allows for fast analyses, small sample volumes, strong enrichment of trace biomarkers and applications in microchips. In this review, the recent research using monolithic materials in the field of bi

  15. Bioaffinity chromatography on monolithic supports

    NARCIS (Netherlands)

    Tetala, K.K.R.; Beek, van T.A.

    2010-01-01

    Affinity chromatography on monolithic supports is a powerful analytical chemical platform because it allows for fast analyses, small sample volumes, strong enrichment of trace biomarkers and applications in microchips. In this review, the recent research using monolithic materials in the field of bi

  16. A dual mode charge pump with adaptive output used in a class G audio power amplifier*

    Institute of Scientific and Technical Information of China (English)

    Feng Yong; Peng Zhenfei; Yang Shanshan; Hong Zhiliang; Liu Yang

    2011-01-01

    A dual mode charge pump to produce an adaptive power supply for a class G audio power amplifier is presented. According to the amplitude of the input signals, the charge pump has two level output voltage rails available to save power. It operates both in current mode at high output load and in pulse frequency modulation (PFM) at light load to reduce the power dissipation. Also, dynamic adjustment of the power stage transistor size based on load current at the PFM mode is introduced to reduce the output voltage ripple and prevent the switching frequency from audio range. The prototype is implemented in 0.18μm 3.3 V CMOS technology. Experimental results show that the maximum power efficiency of the charge pump is 79.5% @ 0.5x mode and 83.6% @ lx mode. The output voltage ripple is less than 15 mV while providing 120 mA of the load current at PFM control and less than 18 mV while providing 300 mA of the load current at current mode control. An analytical model for ripple voltage and efficiency calculation of the proposed PFM control demonstrates reasonable agreement with measured results.

  17. A dual mode charge pump with adaptive output used in a class G audio power amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Feng Yong; Peng Zhenfei; Yang Shanshan; Hong Zhiliang [State Key Laboratory of ASIC and System, Fudan University Shanghai 201203 (China); Liu Yang, E-mail: zlhong@fudan.edu.cn [Shanghai Design Center, Analog Devices, Shanghai 200021 (China)

    2011-04-15

    A dual mode charge pump to produce an adaptive power supply for a class G audio power amplifier is presented. According to the amplitude of the input signals, the charge pump has two level output voltage rails available to save power. It operates both in current mode at high output load and in pulse frequency modulation (PFM) at light load to reduce the power dissipation. Also, dynamic adjustment of the power stage transistor size based on load current at the PFM mode is introduced to reduce the output voltage ripple and prevent the switching frequency from audio range. The prototype is implemented in 0.18 {mu}m 3.3 V CMOS technology. Experimental results show that the maximum power efficiency of the charge pump is 79.5% - 0.5x mode and 83.6% - 1x mode. The output voltage ripple is less than 15 mV while providing 120 mA of the load current at PFM control and less than 18 mV while providing 300 mA of the load current at current mode control. An analytical model for ripple voltage and efficiency calculation of the proposed PFM control demonstrates reasonable agreement with measured results. (semiconductor integrated circuits)

  18. A novel low-voltage operational amplifier for low-power pipelined ADCs

    Energy Technology Data Exchange (ETDEWEB)

    Fan Mingjun; Ren Junyan; Guo Yao; Li Ning; Ye Fan; Li Lian, E-mail: 052052003@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 200433 (China)

    2009-01-15

    A novel low-voltage two-stage operational amplifier employing class-AB architecture is presented. The structure utilizes level-shifters and current mirrors to create the class-AB behavior in the first and second stages. With this structure, the transconductances of the two stages are double compared with the normal configuration without class-AB behaviors with the same current consumption. Thus power can be saved and the operation frequency can be increased. The nested cascode miller compensation and symmetric common-mode feedback circuits are used for large unit-gain bandwidth, good phase margin and stability. Simulation results show that the sample-and-hold of the 12-bit 40-Ms/s pipelined ADC using the proposed amplifier consumes only 5.8 mW from 1.2 V power supply with signal-to-noise-and-distortion ratio 89.5 dB, spurious-free dynamic range 95.7 dB and total harmonic distortion -94.3 dB with Nyquist input signal frequency.

  19. A Low-Power 9-bit Pipelined CMOS ADC with Amplifier and Comparator Sharing Technique

    CERN Document Server

    Bocharov, Yuri; Osipov, Dmitry

    2012-01-01

    This paper describes a pipelined analog-to-digital converter (ADC) employing a power and area efficient architecture. The adjacent stages of a pipeline share operational amplifiers. In order to keep accuracy of the amplifiers in the first stages, they use a partially sharing technique. The feature of the proposed scheme is that it also shares the comparators. The capacitors of the first stages of a pipeline are scaled down along a pipeline for a further reducing the chip area and its power consumption. A 9-bit 20-MSamples/s ADC, intended for use in multi-channel mixed-signal chips, has been fabricated via Europractice in a 180-nm CMOS process from UMC. The prototype ADC shows a spurious-free dynamic range of 58.5 dB at a sample rate of 20 MSamples/s, when a 400 kHz input signal with a swing of 1 dB below full scale is applied. The effective number of bits is 8.0 at the same conditions. ADC occupies an active area of 0.4 mm2 and dissipates 8.6 mW at a 1.8 V supply.

  20. A novel low-voltage operational amplifier for low-power pipelined ADCs

    Science.gov (United States)

    Mingjun, Fan; Junyan, Ren; Yao, Guo; Ning, Li; Fan, Ye; Lian, Li

    2009-01-01

    A novel low-voltage two-stage operational amplifier employing class-AB architecture is presented. The structure utilizes level-shifters and current mirrors to create the class-AB behavior in the first and second stages. With this structure, the transconductances of the two stages are double compared with the normal configuration without class-AB behaviors with the same current consumption. Thus power can be saved and the operation frequency can be increased. The nested cascode miller compensation and symmetric common-mode feedback circuits are used for large unit-gain bandwidth, good phase margin and stability. Simulation results show that the sample-and-hold of the 12-bit 40-Ms/s pipelined ADC using the proposed amplifier consumes only 5.8 mW from 1.2 V power supply with signal-to-noise-and-distortion ratio 89.5 dB, spurious-free dynamic range 95.7 dB and total harmonic distortion -94.3 dB with Nyquist input signal frequency.

  1. High-energy femtosecond Yb-doped all-fiber monolithic chirped-pulse amplifier at repetition rate of 1 MHz

    Science.gov (United States)

    Lv, Zhi-Guo; Teng, Hao; Wang, Li-Na; Wang, Jun-Li; Wei, Zhi-Yi

    2016-09-01

    A high-energy femtosecond all ytterbium fiber amplifier based on a chirped-pulse amplification (CPA) technique at a repetition rate of 1 MHz seeded by a dispersion-management mode-locked picosecond broadband oscillator is studied. We find that the compressed pulse duration is dependent on the amplified energy, the pulse duration of 804 fs corresponds to the maximum amplified energy of 10.5 μJ, while the shortest pulse duration of 424 fs corresponds to the amplified energy of 6.75 μJ. The measured energy fluctuation is approximately 0.46% root mean square (RMS) over 2 h. The low-cost femtosecond fiber laser source with super-stability will be widely used in industrial micromachines, medical therapy, and scientific studies. Project supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China (Grant No. 2012BAC23B03), the National Key Basic Research Program of China (Grant No. 2013CB922401), and the National Natural Science Foundation of China (Grant No. 11474002).

  2. Current mirror reset for low-power BiCMOS charge amplifier

    CERN Document Server

    Sampietro, M; Fasoli, L

    2000-01-01

    We present a circuit solution to provide DC feedback and signal reset in charge amplifiers that overcomes the difficulty to integrate high value resistors in VLSI technology. The feedback resistor is substituted by a MOSFET current conveyor that re-direct to the input node the current already available at the output follower. The lower noise of this 'active resistor' with respect to a physical resistor of equal value makes possible a first shaping within the preamplifier. The circuit has been implemented for a fast shaping time system (20 ns peaking time) using a BJT as input transistor for best noise performance. The circuit has been powered with single supply as low as 1.6 V with a total power consumption down to 220 mu W/ch and has shown a measured noise of 660 electrons rms, in accordance with the theoretical expectation.

  3. Maximally Flat Waveforms with Finite Number of Harmonics in Class-F Power Amplifiers

    Directory of Open Access Journals (Sweden)

    Anamarija Juhas

    2013-01-01

    Full Text Available In this paper general solution to the problem of finding maximally flat waveforms with finite number of harmonics (maximally flat trigonometric polynomials is provided. Waveform coefficients are expressed in closed form as functions of harmonic orders. Two special cases of maximally flat waveforms (so-called maximally flat even harmonic and maximally flat odd harmonic waveforms, which proved to play an important role in class-F and inverse class-F power amplifier (PA operations, are also considered. For these two special types of waveforms, coefficients are expressed as functions of two parameters only. Closed form expressions for efficiency and power output capability of class-F and inverse class-F PA operations with maximally flat waveforms are also provided as explicit functions of number of a harmonics.

  4. A 3-5 GHz CMOS UWB power amplifier with {+-}8 ps group delay ripple

    Energy Technology Data Exchange (ETDEWEB)

    Xi Tianzuo; Huang Lu; Zheng Zhong; Feng Lisong, E-mail: xitianzuo@hotmail.co [Department of Electronic Science and Technology, University of Science and Technology of China, Hefei 230027 (China)

    2010-04-15

    A differential power amplifier (PA), designed using the linear-phase filter model, for a BPSK modulated ultra-wideband (UWB) system operating in the 3-5 GHz frequency range is presented. The proposed PA was fabricated using 0.18 {mu}m SMIC CMOS technology. To achieve sufficient linearity and efficiency, this PA operates in the class-AB region, delivering an output power of 8.5 dBm at an input-1 dB compression point of -0.5 dBm. It consumes 28.8 mW, realizing a flat gain of 9.11 {+-} 0.39 dB and a very low group delay ripple of {+-}8 ps across the whole band of operation. (semiconductor integrated circuits)

  5. A Wideband Digital Predistorter for a Doherty Power Amplifier Using a Direct Learning Memory Effect Filter

    Science.gov (United States)

    Horiguchi, Kenichi; Matsunaga, Naoko; Yamauchi, Kazuhisa; Hayashi, Ryoji; Miyazaki, Moriyasu; Nojima, Toshio

    This paper presents a digital predistorter with a wideband memory effect compensator for a Doherty power amplifier (PA). A simple memory-predistortion model, which consists of a look-up-table (LUT) and an adaptive filter equalizing memory effects, and a new memory effect estimation algorithm using a direct-learning architecture are proposed. The proposed estimation algorithm has an advantage that a transfer function of a feedback circuit does not affect the learning process. The predistorter is implemented in a field programmable gate array (FPGA) and a digital signal processor (DSP). The transmitter has achieved distortion level of -50.8dBr at signal bandwidth away from the carrier, and PA module efficiency of 24% with output power of 43dBm at 2595MHz under a 20MHz-bandwidth orthogonal frequency division multiplexing (OFDM) signal using laterally diffused metal oxide semiconductor (LDMOS) FETs.

  6. An integrated low-power lock-in amplifier and its application to gas detection.

    Science.gov (United States)

    Maya-Hernández, Paulina M; Álvarez-Simón, Luis C; Sanz-Pascual, María Teresa; Calvo-López, Belén

    2014-08-27

    This paper presents a new micropower analog lock-in amplifier (LIA) suitable for battery-operated applications thanks to its reduced size and power consumption as well as its operation with single-supply voltage. The proposed LIA was designed in a 0.18 µm CMOS process with a single supply voltage of 1.8 V. Experimental results show a variable DC gain ranging from 24.7 to 42 dB, power consumption of 417 µW and integration area of 0.013 mm2. The LIA performance was demonstrated by measuring carbon monoxide concentrations as low as 1 ppm in dry N2. The experimental results show that the response to CO of the sensing system can be considerably improved by means of the proposed LIA.

  7. Study of dopant concentrations on thermal induced mode instability in high power fiber amplifiers

    CERN Document Server

    Tao, Rumao; Wang, Xiaolin; Zhou, Pu; Liu, Zejin

    2015-01-01

    Dependence of mode instabilities (MI) on ytterbium dopant concentrations in high power fiber amplifiers has been investigated. It is theoretically shown that, by only varying the fiber length to maintain the same total small-signal pump absorption, the MI threshold is independent of dopant concentration. MI thresholds of gain fibers with ytterbium dopant concentration of 5.93X10^25/m3 and 1.02X10^26/m3 have been measured, which exhibit similar thresholds and agree with theoretical results. The result indicates that heavy doping of active fiber can be adopted to suppress nonlinear effects without decreasing MI threshold, which provides a method of maximizing the power output of fiber laser, taking into account the stimulated Brillouin scattering, stimulated Raman Scattering, and MI thresholds simultaneously.

  8. Optimal power allocation to minimize SER for multinode amplify-and-forward cooperative communication systems

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An optimal power allocation (OPA) method with mean channel gains is proposed for a multinode amplify-and-forward cooperative communication system. By making use of M-PSK modulation, a closed-form symbol-error-rate (SER) formulation and corresponding upper bound are first derived. Subsequently the OPA method is utilized to minimize the SER. Comparison of the SER of the proposed OPA method with that of the equal power allocation (EPA) method, shows that the SER of both methods, which is approximately optimal performance, is almost the same when relays are near the source. OPA outperforms the EPA when the relays are near the middle between the source and destination or near the destination. The proposed OPA method depends only on the ratio of mean channel gains of the source-to-relay to those of the relay-to-destination. Extensive simulations are performed to validate the theoretical results.

  9. Modeling Nonlinear Power Amplifiers in OFDM Systems from Subsampled Data: A Comparative Study Using Real Measurements

    Directory of Open Access Journals (Sweden)

    Santamaría Ignacio

    2003-01-01

    Full Text Available A comparative study among several nonlinear high-power amplifier (HPA models using real measurements is carried out. The analysis is focused on specific models for wideband OFDM signals, which are known to be very sensitive to nonlinear distortion. Moreover, unlike conventional techniques, which typically use a single-tone test signal and power measurements, in this study the models are fitted using subsampled time-domain data. The in-band and out-of-band (spectral regrowth performances of the following models are evaluated and compared: Saleh's model, envelope polynomial model (EPM, Volterra model, the multilayer perceptron (MLP model, and the smoothed piecewise-linear (SPWL model. The study shows that the SPWL model provides the best in-band characterization of the HPA. On the other hand, the Volterra model provides a good trade-off between model complexity (number of parameters and performance.

  10. An Integrated Low-Power Lock-In Amplifier and Its Application to Gas Detection

    Directory of Open Access Journals (Sweden)

    Paulina M. Maya-Hernández

    2014-08-01

    Full Text Available This paper presents a new micropower analog lock-in amplifier (LIA suitable for battery-operated applications thanks to its reduced size and power consumption as well as its operation with single-supply voltage. The proposed LIA was designed in a 0.18 µm CMOS process with a single supply voltage of 1.8 V. Experimental results show a variable DC gain ranging from 24.7 to 42 dB, power consumption of 417 µW and integration area of 0.013 mm2. The LIA performance was demonstrated by measuring carbon monoxide concentrations as low as 1 ppm in dry N2. The experimental results show that the response to CO of the sensing system can be considerably improved by means of the proposed LIA.

  11. Simultaneous Wireless Information and Power Transfer for MIMO Amplify-and-Forward Relay Systems

    KAUST Repository

    Benkhelifa, Fatma

    2016-03-28

    © 2015 IEEE. In this paper, we investigate two-hop Multiple- Input Multiple-Output (MIMO) Amplify-and-Forward (AF) relay communication systems with simultaneous wireless information and power transfer (SWIPT) at the multi-antenna energy harvesting relay. We derive the optimal source and relay covariance matrices to characterize the achievable region between the source-destination rate and the harvested energy at the relay, namely Rate-Energy (R-E) region. In this context, we consider the ideal scenario where the energy harvester (EH) receiver and the information decoder (ID) receiver at the relay can simultaneously decode the information and harvest the energy at the relay. This scheme provides an outer bound for the achievable R-E region since practical energy harvesting circuits are not yet able to harvest the energy and decode the information simultaneously. Then, we consider more practical schemes which are the power splitting (PS) and the time switching (TS) proposed in [1] and which separate the EH and ID transfer over the power domain and the time domain, respectively. In our study, we derive the boundary of the achievable R- E region and we show the effect of the source transmit power, the relay transmit power and the position of the relay between the source and the destination on the achievable R-E region for the ideal scenario and the two practical schemes.

  12. Low-Loss Matching Network Design for Band-Switchable Multi-Band Power Amplifier

    Science.gov (United States)

    Fukuda, Atsushi; Furuta, Takayuki; Okazaki, Hiroshi; Narahashi, Shoichi; Nojima, Toshio

    This paper presents a novel design scheme for a band-switchable multi-band power amplifier (BS-MPA). A key point of the design scheme is configuring multi-section reconfigurable matching networks (MR-MNs) optimally in terms of low loss matching in multiple frequency bands from 0.7 to 2.5GHz. The MR-MN consists of several matching sections, each of which has a matching block connected to a transmission line via a switch. Power dissipation at an actual on-state switch results in the insertion loss of the MR-MN and depends on how the impedance is transformed by the MR-MN. The proposed design scheme appropriately transforms the impedance of a high power transistor to configure a low loss MR-MN. Numerical analyses show quantitative improvement in the loss using the proposed scheme. A 9-band 3-stage BS-MPA is newly designed following the proposed scheme and fabricated on a multi-layer low temperature co-fired ceramic substrate for compactness. The BS-MPA achieves a gain of over 30dB, an output power of greater than 33dBm and a power added efficiency of over 40% at the supply voltage of 4V in each operating band.

  13. Joint Subchannel Pairing and Power Control for Cognitive Radio Networks with Amplify-and-Forward Relaying

    Science.gov (United States)

    Shen, Yanyan; Wang, Shuqiang; Wei, Zhiming

    2014-01-01

    Dynamic spectrum sharing has drawn intensive attention in cognitive radio networks. The secondary users are allowed to use the available spectrum to transmit data if the interference to the primary users is maintained at a low level. Cooperative transmission for secondary users can reduce the transmission power and thus improve the performance further. We study the joint subchannel pairing and power allocation problem in relay-based cognitive radio networks. The objective is to maximize the sum rate of the secondary user that is helped by an amplify-and-forward relay. The individual power constraints at the source and the relay, the subchannel pairing constraints, and the interference power constraints are considered. The problem under consideration is formulated as a mixed integer programming problem. By the dual decomposition method, a joint optimal subchannel pairing and power allocation algorithm is proposed. To reduce the computational complexity, two suboptimal algorithms are developed. Simulations have been conducted to verify the performance of the proposed algorithms in terms of sum rate and average running time under different conditions. PMID:25045731

  14. High average power picosecond pulse and supercontinuum generation from a thulium-doped, all-fiber amplifier.

    Science.gov (United States)

    Liu, Jiang; Xu, Jia; Liu, Kun; Tan, Fangzhou; Wang, Pu

    2013-10-15

    We demonstrate a high-power, picosecond, thulium-doped, all-fiber master oscillator power amplifier with average power of 120.4 W. The compact fiber oscillator is carefully designed with high repetition rate for the purpose of overcoming the detrimental effects of fiber nonlinearity in the later fiber amplifiers. The pulse duration of 16 ps at 333.75 MHz repetition rate results in a peak power of 22.5 kW in the final fiber power amplifier. To the best of our knowledge, this is the first demonstration of average power exceeding 100 W from an ultrashort pulse laser at 2 μm wavelength. On the other hand, by decreasing the fiber oscillator repetition rate and pulse duration for enhancing the fiber nonlinearity effects, we also demonstrate a high-power supercontinuum source with average power of 36 W from 1.95 μm to beyond 2.4 μm in the final fiber power amplifier.

  15. Fabrication of Very High Efficiency 5.8 GHz Power Amplifiers using AlGaN HFETs on SiC Substrates for Wireless Power Transmission

    Science.gov (United States)

    Sullivan, Gerry

    2001-01-01

    For wireless power transmission using microwave energy, very efficient conversion of the DC power into microwave power is extremely important. Class E amplifiers have the attractive feature that they can, in theory, be 100% efficient at converting, DC power to RF power. Aluminum gallium nitride (AlGaN) semiconductor material has many advantageous properties, relative to silicon (Si), gallium arsenide (GaAs), and silicon carbide (SiC), such as a much larger bandgap, and the ability to form AlGaN/GaN heterojunctions. The large bandgap of AlGaN also allows for device operation at higher temperatures than could be tolerated by a smaller bandgap transistor. This could reduce the cooling requirements. While it is unlikely that the AlGaN transistors in a 5.8 GHz class E amplifier can operate efficiently at temperatures in excess of 300 or 400 C, AlGaN based amplifiers could operate at temperatures that are higher than a GaAs or Si based amplifier could tolerate. Under this program, AlGaN microwave power HFETs have been fabricated and characterized. Hybrid class E amplifiers were designed and modeled. Unfortunately, within the time frame of this program, good quality HFETs were not available from either the RSC laboratories or commercially, and so the class E amplifiers were not constructed.

  16. High-power coherent GaAs-based monolithic semiconductor lasers

    Science.gov (United States)

    Botez, Dan

    2001-11-01

    Stable-beam operation to high coherent powers from large aperture devices can only be obtained from active-photonic- lattice (APL) structures of large built-in index step. Resonant phase-locked arrays of antiguides, so called ROW array, have provided 1.6W CW coherent power from 200micrometers - wide apertures. Two-dimensional surface-emitting APLs combining ROW arrays and DFB-DBR structures with central (pi) phase-shift are capable of providing coherent powers in the multi-watt range. ARROW-type devices, simpler APL structures, hold the potential for emitting 1W single-mode CW power reliability in stable beam patterns.

  17. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications

  18. Highly efficient high power single-mode fiber amplifier utilizing the distributed mode filtering bandgap rod fiber

    DEFF Research Database (Denmark)

    Laurila, Marko; Alkeskjold, Thomas T.; Jørgensen, Mette Marie

    2012-01-01

    We report on an ytterbium doped single mode distributed mode filtering rod fiber in an amplifier configuration delivering high average output power, up to 292 watts, using a mode-locked 30ps source at 1032nm with good power conversion efficiency. We study the modal stability of the output beam...

  19. Design of InP DHBT power amplifiers at millimeter-wave frequencies using interstage matched cascode technique

    DEFF Research Database (Denmark)

    Yan, Lei; Johansen, Tom Keinicke

    2013-01-01

    In this paper, the design of InP DHBT based millimeter-wave(mm-wave) power amplifiers(PAs) using an interstage matched cascode technique is presented. The output power of a traditional cascode is limited by the early saturation of the common-base(CB) device. The interstage matched cascode can be ...

  20. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications t

  1. Design and Analysis of a 34 dBm Ka-Band GaN High Power Amplifier MMIC

    NARCIS (Netherlands)

    Heijningen, M. van; Vliet, F.E. van; Quay, R.; Raay, F. van; Seelmann-Eggebert, M.

    2006-01-01

    This paper presents the design and analysis issues related to the use of recent GaN technologies for realizing high power millimeter wave MMICs. Two GaN Ka-band amplifier MMICs have been designed, fabricated and characterized. The small-signal and power measurement results are presented for both amp

  2. 94 GHz power amplifier MMIC development in state of the art MHEMT and AlGaN/GaN technology

    NARCIS (Netherlands)

    Heijningen, M. van; Bent, G. van der; Rodenburg, M.; Vliet, F.E. van; Quay, R.; Brückner, P.; Schwantuschke, D.; Jukkala, P.; Narhi, T.

    2012-01-01

    Solid-state power amplifiers at W-band (75 - 110 GHz) are attractive for the generation of local-oscillator (LO) power for super-heterodyne receivers operating at sub-millimetre wave frequencies, as needed for example in future space instruments for Earth observation. Apart from space applications t

  3. Modularity and rates of evolutionary change in a power-amplified prey capture system.

    Science.gov (United States)

    Claverie, Thomas; Patek, S N

    2013-11-01

    The dynamic interplay among structure, function, and phylogeny form a classic triad of influences on the patterns and processes of biological diversification. Although these dynamics are widely recognized as important, quantitative analyses of their interactions have infrequently been applied to biomechanical systems. Here we analyze these factors using a fundamental biomechanical mechanism: power amplification. Power-amplified systems use springs and latches to generate extremely fast and powerful movements. This study focuses specifically on the power amplification mechanism in the fast raptorial appendages of mantis shrimp (Crustacea: Stomatopoda). Using geometric morphometric and phylogenetic comparative analyses, we measured evolutionary modularity and rates of morphological evolution of the raptorial appendage's biomechanical components. We found that "smashers" (hammer-shaped raptorial appendages) exhibit lower modularity and 10-fold slower rates of morphological change when compared to non-smashers (spear-shaped or undifferentiated appendages). The morphological and biomechanical integration of this system at a macroevolutionary scale and the presence of variable rates of evolution reveal a balance between structural constraints, functional variation, and the "roles of development and genetics" in evolutionary diversification. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  4. Silicon Carbide MOSFET-Based Switching Power Amplifier for Precision Magnet Control

    Science.gov (United States)

    Miller, Kenneth; Ziemba, Timothy; Prager, James; Picard, Julian

    2016-10-01

    Eagle Harbor Technologies, Inc. (EHT) is using the latest in solid-state switching technologies to advance the state-of-the-art in magnet control for fusion science. Silicon carbide (SiC) MOSFETs offer advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities. When comparing SiC and traditional silicon-based MOSFETs, SiC MOSFETs provide higher current carrying capability allowing for smaller package weights and sizes and lower operating temperature. To validate the design, EHT has developed a low-power switching power amplifier (SPA), which has been used for precision control of magnetic fields, including rapidly changing the fields in coils. This design has been incorporated in to a high power SPA, which has been bench tested. This high power SPA will be tested at the Helicity Injected Torus (HIT) at the University of Washington. Following successful testing, EHT will produce enough SiC MOSFET-based SPAs to replace all of the units at HIT, which allows for higher frequency operation and an overall increase in pulsed current levels.

  5. Design of High-Voltage Switch-Mode Power Amplifier Based on Digital-Controlled Hybrid Multilevel Converter

    Directory of Open Access Journals (Sweden)

    Yanbin Hou

    2016-01-01

    Full Text Available Compared with conventional Class-A, Class-B, and Class-AB amplifiers, Class-D amplifier, also known as switching amplifier, employs pulse width modulation (PWM technology and solid-state switching devices, capable of achieving much higher efficiency. However, PWM-based switching amplifier is usually designed for low-voltage application, offering a maximum output voltage of several hundred Volts. Therefore, a step-up transformer is indispensably adopted in PWM-based Class-D amplifier to produce high-voltage output. In this paper, a switching amplifier without step-up transformer is developed based on digital pulse step modulation (PSM and hybrid multilevel converter. Under the control of input signal, cascaded power converters with separate DC sources operate in PSM switch mode to directly generate high-voltage and high-power output. The relevant topological structure, operating principle, and design scheme are introduced. Finally, a prototype system is built, which can provide power up to 1400 Watts and peak voltage up to ±1700 Volts. And the performance, including efficiency, linearity, and distortion, is evaluated by experimental tests.

  6. SEMICONDUCTOR INTEGRATED CIRCUITS A 900 MHz, 21 dBm CMOS linear power amplifier with 35% PAE for RFID readers

    Science.gov (United States)

    Kefeng, Han; Shengguo, Cao; Xi, Tan; Na, Yan; Junyu, Wang; Zhangwen, Tang; Hao, Min

    2010-12-01

    A two-stage differential linear power amplifier (PA) fabricated by 0.18 μm CMOS technology is presented. An output matching and harmonic termination network is exploited to enhance the output power, efficiency and harmonic performance. Measurements show that the designed PA reaches a saturated power of 21.1 dBm and the peak power added efficiency (PAE) is 35.4%, the power gain is 23.3 dB from a power supply of 1.8 V and the harmonics are well controlled. The total area with ESD protected PAD is 1.2 × 0.55 mm2. System measurements also show that this power amplifier meets the design specifications and can be applied for RFID reader.

  7. Monolithic spectrometer

    Science.gov (United States)

    Rajic, Slobodan; Egert, Charles M.; Kahl, William K.; Snyder, Jr., William B.; Evans, III, Boyd M.; Marlar, Troy A.; Cunningham, Joseph P.

    1998-01-01

    A monolithic spectrometer is disclosed for use in spectroscopy. The spectrometer is a single body of translucent material with positioned surfaces for the transmission, reflection and spectral analysis of light rays.

  8. Modeling and design of a monolithically integrated power converter on SiC

    Science.gov (United States)

    Yu, L. C.; Sheng, K.; Zhao, J. H.

    2008-10-01

    To fully explore the high temperature and high power density potential of the 4H-SiC material, not only power devices need to be fabricated on SiC, but also the circuitries for signal generation/processing, gate driver and control. In this paper, static and dynamic characteristics of SiC lateral JFET (LJFET) devices are numerically simulated and compact circuit models developed. Based on these models, analog and digital integrated circuits functional blocks such as OPAMP, gate driver and logic gates are then designed and simulated. Finally, a fully integrated power converter including pulse-width-modulation circuit, over-temperature protection circuit and a power boost converter is designed and simulated. The converter has an input of 200 V and an output voltage of 400 V, 2.5 A, operating at 1 kW and 5 MHz.

  9. A Ku band internally matched high power GaN HEMT amplifier with over 30% of PAE

    Science.gov (United States)

    Qin, Ge; Xiaojuan, Chen; Weijun, Luo; Tingting, Yuan; Yan, Pu; Xinyu, Liu

    2012-01-01

    We report a high power Ku band internally matched power amplifier (IMPA) with high power added efficiency (PAE) using 0.3 μm AlGaN/GaN high electron mobility transistors (HEMTs) on 6H-SiC substrate. The internal matching circuit is designed to achieve high power output for the developed devices with a gate width of 4 mm. To improve the bandwidth of the amplifier, a T type pre-matching network is used at the input and output circuits, respectively. After optimization by a three-dimensional electromagnetic (3D-EM) simulator, the amplifier demonstrates a maximum output power of 42.5 dBm (17.8 W), PAE of 30% to 36.4% and linear gain of 7 to 9.3 dB over 13.8-14.3 GHz under a 10% duty cycle pulse condition when operated at Vds = 30 V and Vgs = -4 V. At such a power level and PAE, the amplifier exhibits a power density of 4.45 W/mm.

  10. A Ku band internally matched high power GaN HEMT amplifier with over 30%of PAE

    Institute of Scientific and Technical Information of China (English)

    Ge Qin; Chen Xiaoiuan; Luo Weijun; Yuan Tingting; Pu Yan; Liu Xinyu

    2012-01-01

    We report a high power Ku band internally matched power amplifier (IMPA) with high power added efficiency (PAE) using 0.3 μm AlGaN/GaN high electron mobility transistors (HEMTs) on 6H-SiC substrate.The internal matching circuit is designed to achieve high power output for the developed devices with a gate width of 4 mm.To improve the bandwidth of the amplifier,a T type pre-matching network is used at the input and output circuits,respectively.After optimization by a three-dimensional electromagnetic (3D-EM) simulator,the amplifier demonstrates a maximum output power of 42.5 dBm (17.8 W),PAE of 30% to 36.4% and linear gain of 7 to 9.3 dB over 13.8-14.3 GHz under a 10% duty cycle pulse condition when operated at Vds =30 V and Vgs =-4 V.At such a power level and PAE,the amplifier exhibits a power density of 4.45 W/mm.

  11. Self-heating and memory effects in RF power amplifiers explained through electro-thermal

    DEFF Research Database (Denmark)

    Wei, Wei; Jensen, Ole Kiel; Mikkelsen, Jan H.

    2013-01-01

    a simple electro-thermal model and shows how self-heating can generate different types of memory effects, such as bandwidth dependent intermodulation components and hysteresis loops. In addition, it is shown that self-heating can result in generation of new spectral components even in an otherwise linear......Self-heating has already been proven to be one of the key sources to memory effects in RF power amplifiers (PAs). However, mechanisms behind the generation of memory effects, as caused by self-heating have not been well documented. On basis of transistor physical properties this paper proposes...... PA. A time domain modeling framework is implemented to investigate memory effects generated by self-heating and simulation results are shown to agree with theoretical analysis....

  12. Study on Volterra-Laguerre behavioral model for RF power amplifier

    Institute of Scientific and Technical Information of China (English)

    Nan Jingchang; Liu Yuanan; Tang Bihua

    2007-01-01

    Volterra series behavioral model for radio frequency(RF)power amplifier(PA)has been widely used in system-level simulation,however,high computational complexity makes this kind of model limited to"weak"nonlinearity.In order to reduce the computational complexity and the number of coefficients of Volterra series kernels,a Volterra series improved behavioral model based on Lasuerre orthogonal polynomials function,namely Volterra-Laguerre behavioral model,is proposed.Mathematical expressions of Volterra-Laguerre behavioral model is derived.and accuracy of the model is verified through comparison of measured and simulation output data from a freescale PA using MRF21030 transistor.Mathematical analysis and simulation results show that Volterra-Laguerre behavioral model has a simple structure,much less coefficients and better modeling performance than general Volterra series model.The model can be used more correctly for system-level simulation of RF PA with wideband signal.

  13. Adaptive Digital Predistortion Schemes to Linearize RF Power Amplifiers with Memory Effects

    Institute of Scientific and Technical Information of China (English)

    ZHANG Peng; WU Si-liang; ZHANG Qin

    2008-01-01

    To compensate for nonlinear distortion introduced by RF power amplifiers (PAs) with memory effects, two correlated models, namely an extended memory polynomial (EMP) model and a memory lookup table (LUT) model, are proposed for predistorter design. Two adaptive digital predistortion (ADPD) schemes with indirect learning architecture are presented. One adopts the EMP model and the recursive least square (RLS) algorithm, and the other utilizes the memory LUT model and the least mean square (LMS) algorithm. Simulation results demonstrate that the EMP-based ADPD yields the best linearization performance in terms of suppressing spectral regrowth. It is also shown that the ADPD based on memory LUT makes optimum tradeoff between performance and computational complexity.

  14. Volterra series based predistortion for broadband RF power amplifiers with memory effects

    Institute of Scientific and Technical Information of China (English)

    Jin Zhe; Song Zhihuan; He Jiaming

    2008-01-01

    RF power amplifiers(PAs)are usually considered as memoryless devices in most existing predistortion techniques.However,in broadband communication systems,such as WCDMA,the PA memory effects are significant,and memoryless predistortion cannot linearize the PAs effectively.After analyzing the PA memory effects,a novel predistortion method based on the simplified Volterra series is proposed to linearize broadband RF PAs with memory effects.The indirect learning architecture is adopted to design the predistortion scheme and the recursive least squares algorithm with forgetting factor is applied to identify the parameters of the predistorter.Simulation results show that the proposed predistortion method can compensate the nonlinear distortion and memory effects of broadband RF PAs effectively.

  15. Numerical Analysis of a Cold Plate for FM Radio Power Amplifiers

    Science.gov (United States)

    Sabin, M.; Piva, S.

    2014-07-01

    The results of a numerical investigation of heat and fluid flow in a liquid cold plate for FM radio power amplifiers are presented. The objective is to verify, by using a commercial CFD code, the performance of a blister cold plate designed to dissipate the heat generated by a known set of electronic components, in order to limit their maximum temperature during operations. Since in a blister cold-plate mainly the cover is thermally active, the cold-plate is simplified and lightened by using plastics in the base plate. A 3-D conjugate CFD approach, where thermal and fluid flow analyses are combined, is followed. Several design options for the cold plate are examined and the validity of the full 3-D CFD approach in the dimensioning of the cooling systems of electronic equipment is demonstrated.

  16. Electronically Tunable Impedance-Matching Networks for Intelligent RF Power Amplifiers

    Directory of Open Access Journals (Sweden)

    Liang Li

    2013-11-01

    Full Text Available This paper presents the simulation and optimization design of the electronically tunable impedance-matching networks for intelligent RF power amplifiers in a cognitive radio system. Reconfigurable elements, such as varactors and RF switches are utilized to achieve the dynamic impedance matching both in the input and output matching circuit, providing coarse and fine tuning of the target impedances with low loss and excellent impedance coverage from 500MHz to 800MHz. The topology of varactor model is illustrated to ensure the precision of simulation. In addition, high-precision bias voltage controlling system is designed to improve the nonlinear problem caused by the varactor. The simulation results demonstrate the excellent performance of the tunable networks, satisfying the requirement of the cognitive radio systems.  

  17. Low Power Broadband Low-Noise Amplifiers from 1-300GHz Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A number of low noise amplifier technologies exist at a variety of maturity levels and with a variety of strengths and limitations. The most mature amplifier...

  18. Optimizing high-power Yb-doped fiber amplifier systems in the presence of transverse mode instabilities.

    Science.gov (United States)

    Jauregui, Cesar; Otto, Hans-Jürgen; Breitkopf, Sven; Limpert, J; Tünnermann, A

    2016-04-18

    The average output power of Yb-doped fiber amplifier systems is currently limited by the onset of transverse mode instabilities. Besides, it has been recently shown that the transverse mode instability threshold can be significantly reduced by the presence of photodarkening in the fiber. Therefore, reducing the photodarkening level of the core material composition is the most straightforward way to increase the output average power of fiber amplifier systems but, unfortunately, this is not always easy or possible. In this paper we present guidelines to optimize the output average power of fiber amplifiers affected by transverse mode instabilities and photodarkening. The guidelines derived from the simulations do not involve changes in the composition of the active material (except for its doping concentration), but can still lead to a significant increase of the transverse mode instability threshold. The dependence of this parameter on the active ion concentration and the core conformation, among others, will be studied and discussed.

  19. Integrating switch mode audio amplifiers and electro dynamic loudspeakers for a higher power efficiency

    DEFF Research Database (Denmark)

    Poulsen, Søren; Andersen, Michael Andreas E.

    2004-01-01

    The work presented in this paper is related to integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker's voice coil as output filter, and the magnetic structure as heatsink for the amplifier.......The work presented in this paper is related to integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker's voice coil as output filter, and the magnetic structure as heatsink for the amplifier....

  20. Design of Predistorter with Efficient Updating Algorithm of Power Amplifier with Memory Effect

    Science.gov (United States)

    Oishi, Yasuyuki; Kimura, Shigekazu; Fukuda, Eisuke; Takano, Takeshi; Takago, Daisuke; Daido, Yoshimasa; Araki, Kiyomichi

    This paper describes a method to design a predistorter (PD) for a GaN-FET power amplifier (PA) by using nonlinear parameters extracted from measured IMD which has asymmetrical peaks peculiar to a memory effect with a second-order lag. While, computationally efficient equations have been reported by C. Rey et al. for the memory effect with a first-order lag. Their equations are extended to be applicable to the memory effect with the second-order lag. The extension provides a recursive algorithm for cancellation signals of the PD each of which updating is made by using signals in only two sampling points. The algorithm is equivalent to a memory depth of two in computational efficiency. The required times for multiplications and additions are counted for the updating of all the cancellation signals and it is confirmed that the algorithm reduces computational intensity lower than half of a memory polynomial in recent papers. A computer simulation has clarified that the PD improves the adjacent channel leakage power ratio (ACLR) of OFDM signals with several hundred subcarriers corresponding to 4G mobile radio communications. It has been confirmed that a fifth-order PD is effective up to a higher power level close to 1dB compression. The improvement of error vector magnitude (EVM) by the PD is also simulated for OFDM signals of which the subcarrier channels are modulated by 16 QAM.

  1. Low Power CMOS Operational Amplifier with Integrated Common-Mode Feedback for Data Converter

    Directory of Open Access Journals (Sweden)

    Murad S.A.Z

    2017-01-01

    Full Text Available The development a high-performance design of analog circuits becomes increasingly challenging with the continuous trend towards reducing the voltage supply and low power consumption without neglecting the trade-off among other performance parameters. This paper presents the design and implementation of CMOS operational amplifier (op-amp with integrated common-mode feedback (CMFB circuit for data converter using 0.13-μm Silterra CMOS technology. The folded cascode topology is employed as a main op-amp design because it provides high gain and high bandwidth besides low power consumption. The simulation results indicate that the DC gain of 64.5 dB along 133.1 MHz unity gain bandwidth (UGB is achieved for a 1 pF load capacitor. The slew rate of 22.6 V/μs, the phase margin (PM of 68.4° with settling time of 72.4 ns are obtained. The power consumption of this op-amp is 0.3 mW through voltage supply of 1.8 V.

  2. Low-Power Amplifier-Discriminators for High Time Resolution Detection

    CERN Document Server

    Despeisse, M; Anghinolfi, F; Tiuraniemi, S; Osmic, F; Riedler, P; Kluge, A; Ceccucci, A

    2009-01-01

    Low-power amplifier-discriminators based on a so-called NINO architecture have been developed with high time resolution for the readout of radiation detectors. Two different circuits were integrated in the NINO13 chip, processed in IBM 130 nm CMOS technology. The LCO version (Low Capacitance and consumption Optimization) was designed for potential use as front-end electronics in the Gigatracker of the NA62 experiment at CERN. It was developed as pixel readout for solid-state pixel detectors to permit minimum ionizing particle detection with less than 180 ps rms resolution per pixel on the output pulse, for power consumption below 300 mu W per pixel. The HCO version (High Capacitance Optimization) was designed with 4 mW power consumption per channel to provide timing resolution below 20 ps rms on the output pulse, for charges above 10 fC. Results presented show the potential of the LCO and HCO circuits for the precise timing readout of solid-state detectors, vacuum tubes or gas detectors, for applications in h...

  3. Practical considerations for integrating switch mode audio amplifiers and loudspeakers for a higher power efficiency

    DEFF Research Database (Denmark)

    Poulsen, Søren; Andersen, Michael Andreas E.

    2004-01-01

    An integration of electrodynamic loudspeakers and switch mode amplifiers has earlier been proposed in [1]. The work presented in this paper is related to the practical aspects of integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker’s voice coil as output...... filter, and the magnetic structure as heat sink for the amplifier....

  4. High Power SiGe X-Band (8~10GHz) Heterojunction Bipolar Transistors and Amplifiers

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Limited by increased parasitics and thermal effects as device size increases, current commercial SiGe power HBTs are difficult to operate at X-band (8~ 12GHz) frequencies with adequate power added efficiencies at high power levels. We find that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with a proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, thus permitting these devices to be efficiently operated at X-band frequencies. In this paper,we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8~10GHz. At 10GHz,a 22.5dBm (178mW) RF output power with a concurrent gain of 7.32dB is measured at the peak power-added efficiency of 20.0%, and a maximum RF output power of 24.0dBm (250mW) is achieved from a 20 emitter finger SiGe power HBT. The demonstration of a single-stage X-band medium-power linear MMIC power amplifier is also realized at 8GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7dB,a maximum output power of 23.4dBm,and peak power added efficiency of 16% are achieved from the power amplifier. The MMIC exhibits very low distortion with 3rd order intermodulation (IM) suppression C/I of -13dBc at an output power of 21.2dBm and over 20dBm 3rd order output intercept point (OIP3).

  5. A high-linearity SiGe RF power amplifier for 3G and 4G small basestations

    OpenAIRE

    Johansson, Ted; Solati, Noora; Fritzin, Jonas

    2012-01-01

    This article presents the design and evaluation of a linear 3.3V SiGe power amplifier for 3G and 4G femtocells with 18dBm modulated output power at 2140 MHz. Different biasing schemes to achieve high linearity with low standby current were studied. The adjacent channel power ratio linearity performance with wide-band code division multiple access (3G) and long term evolution (4G) downlink signals were compared and differences analysed and explained.

  6. High Power (35 kW and 190 kW) 352 Solid State Amplifiers for the SOLEIL Synchrotron

    CERN Document Server

    Marchand, Patrick; Lopes, Robert; Polian, Jean; Ribeiro, Fernand; Ruan, Ti

    2005-01-01

    In the SOLEIL Storage Ring, two cryomodules, each containing a pair of superconducting cavities will provide the maximum power of 600 kW, required at the nominal energy of 2.75 GeV with the full beam current of 500 mA and all the insertion devices. Each of the four cavities will be powered with a 190 kW solid state amplifier consisting in a combination of 315 W elementary modules (about 750 modules per amplifier). The amplifier modules, based on a technology developed in house, with MOSFET transistor, integrated circulator and individual power supply, are fabricated in the industry. In the booster, a 35 kW solid state amplifier (147 modules) will power a 5-cell copper cavity of the LEP type. The first operational results and the status of the RF power plants are reported in this paper. Although quite innovative for the required power range, the solid state technology proved to be very attractive with significant advantages as compared to vacuum tubes.

  7. Theoretical analysis and an improvement method of the bias effect on the linearity of RF linear power amplifiers

    Institute of Scientific and Technical Information of China (English)

    Wu Tuo; Chen Hongyi; Qian Dahong

    2009-01-01

    Based on the Gummel-Poon model of BJT, the change of the DC bias as a function of the AC input signal in RF linear power amplifiers is theoretically derived, so that the linearity of different DC bias circuits can be interpreted and compared. According to the analysis results, a quantitative adaptive DC bias circuit is proposed,which can improve the linearity and efficiency. From the simulation and test results, we draw conclusions on how to improve the design of linear power amplifier.

  8. High-Bandwidth, High-Efficiency Envelope Tracking Power Supply for 40W RF Power Amplifier Using Paralleled Bandpass Current Sources

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2005-01-01

    This paper presents a high-performance power conversion scheme for power supply applications that require very high output voltage slew rates (dV/dt). The concept is to parallel 2 switching bandpass current sources, each optimized for its passband frequency space and the expected load current....... The principle is demonstrated with a power supply, designed for supplying a 40 W linear RF power amplifier for efficient amplification of a 16-QAM modulated data stream...

  9. High-power monolithic single-mode diode lasers employing active photonic lattices

    Science.gov (United States)

    Botez, Dan

    2003-06-01

    Photonic-lattice structures with modulated gain, that is active photonic lattices (APLs), of large index steps and gain preferentially enhanced on the low-index lattice sites have been used, as early as 1988, for effective lateral-mode control range in large-aperture (100-200 microns) high-power coherent devices. Photonic-bandpass (PBP) structures relying on long-range resonant leaky-wave coupling, so called ROW arrays, have allowed stable, near-diffraction-limited beam operation to powers as high as 1.6W CW and 10W peak pulsed. Photonic-bandgap (PBG) structures with a built-in lattice defect, so called ARROW lasers, have provided up to 0.5W peak-pulsed stable, single-mode power and hold the potential for 1W CW reliable single-mode operation from apertures 8-10 microns wide. The solution for high-efficiency surface emission, from 2nd-order DFB/DBR lasers, in an orthonormal, single-lobe beam pattern was found in 2000. Recently, single-lobe and single-mode operation in a diffraction-limited beam orthonormal to the chip surface was demonstrated from 1.5mm-long DFB/DBR ridge-guide lasers. That opens the way for the realization of 2-D surface-emitting,2nd-order APLs for the stable generation of watts of CW single-lobe, single-mode power from large 2-D apertures, as well as scalability of such devices at the wafer level.

  10. A compact broadband high efficient X-band 9-watt PHEMT MMIC high-power amplifier for phased array radar applications

    NARCIS (Netherlands)

    Hek, A.P. de; Hunneman, P.A.H.; Demmler, M.; Hulsmann, A.

    1999-01-01

    ln this paper the development and measurement results of a compact broadband 9-Watt high efficient X-band high-power amplifier are discussed. The described amplifier has the following state-of-the art performance: an average ouput power of 9 Watt, a gain of 20 dB and an average Power Added

  11. A compact broadband high efficient X-band 9-watt PHEMT MMIC high-power amplifier for phased array radar applications

    NARCIS (Netherlands)

    Hek, A.P. de; Hunneman, P.A.H.; Demmler, M.; Hulsmann, A.

    1999-01-01

    ln this paper the development and measurement results of a compact broadband 9-Watt high efficient X-band high-power amplifier are discussed. The described amplifier has the following state-of-the art performance: an average ouput power of 9 Watt, a gain of 20 dB and an average Power Added Efficienc

  12. Compatibility study towards monolithic self-charging power unit based on all-solid thin-film solar module and battery

    Science.gov (United States)

    Sandbaumhüter, Florian; Agbo, Solomon N.; Tsai, Chih-Long; Astakhov, Oleksandr; Uhlenbruck, Sven; Rau, Uwe; Merdzhanova, Tsvetelina

    2017-10-01

    Aiming at the development of a monolithic integrated all-solid-state self-rechargeable power unit, we perform a V-I characteristics compatibility study for the integration of such a device having a thin-film silicon multi-junction photovoltaic (PV) module and a thin-film solid Li//lithium phosphorus oxynitride//LiCoO2 battery. The battery and PV module are connected to mimic a monolithic module-to-storage cell device and the performance of this device in various temperature conditions has been tested. Few issues regarding the matching of the battery and PV module characteristics are identified for improvement. The concept of the integrated all-solid-state PV-battery solution appears viable especially in three-terminal device configuration.

  13. Power amplifier linearization technique with IQ imbalance and crosstalk compensation for broadband MIMO-OFDM transmitters

    Science.gov (United States)

    Gregorio, Fernando; Cousseau, Juan; Werner, Stefan; Riihonen, Taneli; Wichman, Risto

    2011-12-01

    The design of predistortion techniques for broadband multiple input multiple output-OFDM (MIMO-OFDM) systems raises several implementation challenges. First, the large bandwidth of the OFDM signal requires the introduction of memory effects in the PD model. In addition, it is usual to consider an imbalanced in-phase and quadrature (IQ) modulator to translate the predistorted baseband signal to RF. Furthermore, the coupling effects, which occur when the MIMO paths are implemented in the same reduced size chipset, cannot be avoided in MIMO transceivers structures. This study proposes a MIMO-PD system that linearizes the power amplifier response and compensates nonlinear crosstalk and IQ imbalance effects for each branch of the multiantenna system. Efficient recursive algorithms are presented to estimate the complete MIMO-PD coefficients. The algorithms avoid the high computational complexity in previous solutions based on least squares estimation. The performance of the proposed MIMO-PD structure is validated by simulations using a two-transmitter antenna MIMO system. Error vector magnitude and adjacent channel power ratio are evaluated showing significant improvement compared with conventional MIMO-PD systems.

  14. High-Efficiency, High-Power Ka-Band Elliptic-Beam Traveling-Wave-Tube Amplifier for Long-Range Space RF Telecommunications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space telecommunications require amplifiers that are efficient, high-power, wideband, small, lightweight, and highly reliable. Currently, helix traveling wave tube...

  15. Two-dimensional thermal modeling of power monolithic microwave integrated circuits (MMIC's)

    Science.gov (United States)

    Fan, Mark S.; Christou, Aris; Pecht, Michael G.

    1992-01-01

    Numerical simulations of the two-dimensional temperature distributions for a typical GaAs MMIC circuit are conducted, aiming at understanding the heat conduction process of the circuit chip and providing temperature information for device reliability analysis. The method used is to solve the two-dimensional heat conduction equation with a control-volume-based finite difference scheme. In particular, the effects of the power dissipation and the ambient temperature are examined, and the criterion for the worst operating environment is discussed in terms of the allowed highest device junction temperature.

  16. Ka-Band Wide-Bandgap Solid-State Power Amplifier: Prototype Combiner Spurious Mode Suppression and Power Constraints

    Science.gov (United States)

    Khan, P.; Epp, L.

    2006-01-01

    Results of prototype hardware activities related to a 120-W, 32-GHz (Ka-band) solid-state power amplifier (SSPA) architecture study are presented. Spurious mode suppression and the power-handling capability of a prototype 24-way radial combiner and a prototype 2-way septum binary combiner were investigated. Experimental data indicate that a commercial absorptive filter, designed to pass the circular TE01 mode, effectively suppressed the higher-order modes generated by a narrowband, flower-petal-type mode transducer. However, the same filter was not effective in suppressing higher-order modes generated by the broadband Marie mode transducer that is used in the prototype waveguide radial combiner. Should greater filtering be required by a particular SSPA application, a broadband mode filter that can suppress specifically those higher-order modes that are generated by the Marie transducer will need to be developed. A back-to-back configuration of the prototype radial combiner was tested with drive power up to approximately 50 W. No anomalous behavior was observed. Power measurements of the septum combiner indicate that up to 10-W radio frequency (RF) can be dissipated in the integrated resistive element before a permanent performance shift is observed. Thus, a given adder (a single-stage, 2-way combiner) can safely combine two 20-W sources, and the adder will not be damaged in the event of a source failure. This result is used to calculate the maximum source power that can be safely combined as a function of the number of sources combined and the number of source failures allowed in a multi-stage combiner. The analysis shows that SSPA power >140 W can be generated by power combining 16 sources producing 10 W each. In this configuration, up to three sources could fail with the guarantee that the combiner would not be damaged. Finally, a modified prototype septum combiner design was verified. The improved design reduced the assembly time from over 2 hours to about 15

  17. Back End of Line Nanorelays for Ultra-low Power Monolithic Integrated NEMS-CMOS Circuits

    KAUST Repository

    Lechuga Aranda, Jesus Javier

    2016-05-01

    Since the introduction of Complementary-Metal-Oxide-Semiconductor (CMOS) technology, the chip industry has enjoyed many benefits of transistor feature size scaling, including higher speed and device density and improved energy efficiency. However, in the recent years, the IC designers have encountered a few roadblocks, namely reaching the physical limits of scaling and also increased device leakage which has resulted in a slow-down of supply voltage and power density scaling. Therefore, there has been an extensive hunt for alternative circuit architectures and switching devices that can alleviate or eliminate the current crisis in the semiconductor industry. The Nano-Electro-Mechanical (NEM) relay is a promising alternative switch that offers zero leakage and abrupt turn-on behaviour. Even though these devices are intrinsically slower than CMOS transistors, new circuit design techniques tailored for the electromechanical properties of such devices can be leveraged to design medium performance, ultra-low power integrated circuits. In this thesis, we deal with a new generation of such devices that is built in the back end of line (BEOL) CMOS process and is an ideal option for full integration with current CMOS transistor technology. Simulation and verification at the circuit and system level is a critical step in the design flow of microelectronic circuits, and this is especially important for new technologies that lack the standard design infrastructure and well-known verification platforms. Although most of the physical and electrical properties of NEM structures can be simulated using standard electronic automation software, there is no report of a reliable behavioural model for NEMS switches that enable large circuit simulations. In this work, we present an optimised model of a BEOL nano relay that encompasses all the electromechanical characteristics of the device and is robust and lightweight enough for VLSI applications that require simulation of thousands of

  18. Compact and high-power broadband terahertz source based on femtosecond photonic crystal fiber amplifier

    Institute of Scientific and Technical Information of China (English)

    Feng Liu; Lu Chai; Qirong Xing; Chingyue Wang; Weili Zhang; Xiaokun Hu; Jiang Li; Changlei Wang; Yi Li; Yanfeng Li; YoujianSong; Bowen Liu; Minglie Hu

    2011-01-01

    Terahertz (THz) waves,generally defined in the 0.1-10 THz range are finding growing applications in various important fields[1-4] such as imaging,food and pharmaceutical quality coutrol,security screening,and standoff detection of bio-threat species,among which THz timedomain spectroscopy (THz-TDS)[5] is particularly appealing.However,the low conversion efficiency and low power of typical broadband THz sources severely hinder the utility and realization of the full potential of THzTDS.Recently,there have been efforts to generate THz pulses using compact pump sources in fiber format[6,7].%We present a review of the development of a compact and high-power broadband terahertz (THz) source optically excited by a femtosecond photonic crystal fiber (PCF) amplifier. The large mode area of the PCF and the stretcher-free configuration make the pump source compact and very efficient. Broadband THz pulseg of 150 μW extending from 0.1 to 3.5 TH2 are generated from a 3-mm-thick GaP crystal through optical rectification of 12-W pump pulses with duration of 66 & and a repetition rate of 52 MHz. A strong saturation effect is observed, which is attributed to pump pulse absorption; a Z-scan measurement shows that three-photon absorption dominates the nonlinear absorption when the crystal is pumped by femtosecond pulses at 1040 run. A further scale-up of the THz source power is expected to find important applications in THz nonlinear optics and nonlinear THz spectroscope

  19. RF power upgrade at the superconducting 1.3 GHz CW LINAC “ELBE” with solid state amplifiers

    Energy Technology Data Exchange (ETDEWEB)

    Büttig, Hartmut, E-mail: buettig@hzdr.de [Radiation Source ELBE, Helmholtz Zentrum Dresden-Rossendorf (Germany); Arnold, A.; Büchner, A.; Justus, M.; Kuntsch, M.; Lehnert, U.; Michel, P.; Schurig, R.; Staats, G.; Teichert, J. [Radiation Source ELBE, Helmholtz Zentrum Dresden-Rossendorf (Germany)

    2013-03-11

    The RF power for the superconducting 1.3 GHz CW LINAC “ELBE” has been doubled from less than 10 kW to 20 kW per cavity. In January 2012 the four 10 kW klystrons used to drive the four superconducting cavities of the LINAC have been replaced by pairs of 10 kW solid state power amplifiers (SSPA). ELBE is now worldwide the first 1.3 GHz CW LINAC equipped with solid state RF power amplifiers. This technical note details on this project. -- Highlights: ► We report the first installation of 10 kW solid state RF-amplifiers at 1.3 GHz CW LINAC. ► The sc. cavities of “ELBE” are now driven by a pair of 10 kW solid state amplifiers (SSPA). ► The RF-power upgrade allows doubling the electron beam current (CW). ► Advantages of the new RF system are high reliability, easy service and lower costs.

  20. Microwave phase shifter with controllable power response based on slow-and fast-light effects in semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Xue, Weiqi; Sales, Salvador; Capmany, Jose

    2009-01-01

    We suggest and experimentally demonstrate a method for increasing the tunable rf phase shift of semiconductor waveguides while at the same time enabling control of the rf power. This method is based on the use of slow- and fast-light effects in a cascade of semiconductor optical amplifiers combined...

  1. Efficient fiber-laser-pumped Ho:YLF oscillator and amplifier utilizing the transmitted pump power of the oscillator

    CSIR Research Space (South Africa)

    Strauss, HJ

    2009-06-01

    Full Text Available In this paper, researchers have demonstrated that a Ho:YLF oscillator and amplifier system can be designed in a compact setup where the pump power from an unpolarized fibre laser utilized efficiently. The system produced more than 20 mJ energy per...

  2. Monolithic solid oxide fuel cell technology advancement for coal-based power generation

    Science.gov (United States)

    1994-05-01

    This project has successfully advanced the technology for MSOFC's for coal-based power generation. Major advances include: tape-calendering processing technology, leading to 3X improved performance at 1000 C; stack materials formulations and designs with sufficiently close thermal expansion match for no stack damage after repeated thermal cycling in air; electrically conducting bonding with excellent structural robustness; and sealants that form good mechanical seals for forming manifold structures. A stack testing facility was built for high-spower MSOFC stacks. Comprehensive models were developed for fuel cell performance and for analyzing structural stresses in multicell stacks and electrical resistance of various stack configurations. Mechanical and chemical compatibility properties of fuel cell components were measured; they show that the baseline Ca-, Co-doped interconnect expands and weakens in hydrogen fuel. This and the failure to develop adequate sealants were the reason for performance shortfalls in large stacks. Small (1-in. footprint) two-cell stacks were fabricated which achieved good performance (average area-specific-resistance 1.0 ohm-sq cm per cell); however, larger stacks had stress-induced structural defects causing poor performance.

  3. A Compact Two-Stage 120 W GaN High Power Amplifier for SweepSAR Radar Systems

    Science.gov (United States)

    Thrivikraman, Tushar; Horst, Stephen; Price, Douglas; Hoffman, James; Veilleux, Louise

    2014-01-01

    This work presents the design and measured results of a fully integrated switched power two-stage GaN HEMT high-power amplifier (HPA) achieving 60% power-added efficiency at over 120Woutput power. This high-efficiency GaN HEMT HPA is an enabling technology for L-band SweepSAR interferometric instruments that enable frequent repeat intervals and high-resolution imagery. The L-band HPA was designed using space-qualified state-of-the-art GaN HEMT technology. The amplifier exhibits over 34 dB of power gain at 51 dBm of output power across an 80 MHz bandwidth. The HPA is divided into two stages, an 8 W driver stage and 120 W output stage. The amplifier is designed for pulsed operation, with a high-speed DC drain switch operating at the pulsed-repetition interval and settles within 200 ns. In addition to the electrical design, a thermally optimized package was designed, that allows for direct thermal radiation to maintain low-junction temperatures for the GaN parts maximizing long-term reliability. Lastly, real radar waveforms are characterized and analysis of amplitude and phase stability over temperature demonstrate ultra-stable operation over temperature using integrated bias compensation circuitry allowing less than 0.2 dB amplitude variation and 2 deg phase variation over a 70 C range.

  4. A novel matching network employing surface acoustic wave devices for W-CDMA power amplifiers.

    Science.gov (United States)

    Li, Honglang; He, Songbai; Hashimoto, Ken-ya; Omori, Tatsuya; Yamaguchi, Masatsune

    2006-12-22

    This paper describes a new approach of designing high Q surface acoustic wave (SAW) resonators as an inductive element in the matching network for W-CDMA power amplifiers (PAs). Spiral inductors based on CMOS/BiCMOS technologies presently possess relatively low Q (typically <10) and occupy a considerably large area. In order to break through the limitations of the spiral inductors, the authors attempt to apply higher Q and wideband SAW resonators employing Cu-grating/15 degrees YX-LiNbO(3)-substrate structure to the matching network for improved PA performance. An analysis was made on SAW resonators in detail, and an SAW resonator having a very small capacitance ratio of 3.28 and moderate Q of 147.8 was developed. After discussing the frequency dependence of the effective inductances, SAW resonators, which are used to be as inductive elements in the matching networks of PAs, were designed and fabricated. The PA including the matching circuit was simulated using the characteristics of the fabricated SAW resonators. The result showed that with better shape factor and good out-of-rejection, the SAW resonators definitely work as an inductive element and could replace widely used spiral inductors.

  5. Optimal Configuration of Multiple Pump Powers and Wavelengths for Balanced Pre- and Post-pumped Raman Fiber Amplifiers

    Institute of Scientific and Technical Information of China (English)

    YAN Minhui; CHEN Jianping; LI Jianlang; JIANG Wenning; CHEN Junfeng; LI Xin

    2002-01-01

    A novel configuration algorithm for bi-directionally pumped Raman amplifier is developed by adopting simulated annealing algorithm. Automatic design of optical fiber Raman amplifier using 10 laser diode pumps with different wavelengths and powers is demonstrated for 64 channels DWDM systems. The resulted gain ripple is less than 2.6 dB in amplification bandwidth of more than 50 nm for a transmission span of more than 300 km. The algorithm can be practically applied to desired signal channel number and gain profile.

  6. Practical considerations for integrating switch mode audio amplifiers and loudspeakers for a higher power efficiency

    DEFF Research Database (Denmark)

    Poulsen, Søren; Andersen, Michael Andreas E.

    2004-01-01

    An integration of electrodynamic loudspeakers and switch mode amplifiers has earlier been proposed in [1]. The work presented in this paper is related to the practical aspects of integration of switch mode audio amplifiers and electro dynamic loudspeakers, using the speaker’s voice coil as output...

  7. Damage behavior of Nd:glass of high-power disk amplifier medium in ICF Facility

    Science.gov (United States)

    He, Shaobo; Chen, Lin; Yuan, Xiaodong; Chen, Yuanbin; Cheng, Xiaofeng; Xie, Xudong; Wang, Wenyi; Zu, Xiaotao

    2016-12-01

    Large aperture Nd:glass disk is often used as the amplifier medium in the inertial confinement fusion (ICF) facilities. The typical size of Nd:glass is up to 810mm×460mm×40mm and more than 3,000 Nd:glass components are needed in the ICF facility. At present, the 3ω fused silica glass and DKDP crystal are mainly responsible for the damage of driver used for ICF. However, with the enlargement of the facility and increase of laser shot number, the laser damage of Nd:glass at 1ω waveband is still an important problem to limit the stable operation of facility and improvement of laser beam quality. In this work, the influence of Nd:glass material itself, mechanical processing, service environment, and laser beam quality on its damage behavior is investigated experimentally and theoretically. The results and conclusions can be summarized as follows: (1) It is very important to control the concentration of platinum impurity particles during melting and the sputtering effect of the cladding materials. (2) The number and length of fractural and brittle scratches should be strictly suppressed during mechanical processing of Nd:glass. (3) The B-integral of high power laser beam should be rigorously controlled. Particularly, the top shape of pulses must be well controlled when operating at high peak laser power. (4) The service environment should be well managed to make sure the cleanness of the surface of Nd:glass better than 100/A level during mounting and running. (5) The service environment and beam quality should be monitored during operation.

  8. Full characterization of the amplified spontaneous emission from a diode-pumped high-power laser system.

    Science.gov (United States)

    Keppler, S; Hornung, M; Bödefeld, R; Sävert, A; Liebetrau, H; Hein, J; Kaluza, M C

    2014-05-01

    We present the first complete temporal and spatial characterization of the amplified spontaneous emission (ASE) of laser radiation generated by a diode-pumped high-power laser system. The ASE of the different amplifiers was measured independently from the main pulse and was characterized within a time window of -10ms ≤ t ≤ 10ms and an accuracy of up to 15fs around the main pulse. Furthermore, the focusability and the energy of the ASE from each amplifier was measured after recompression. Using our analysis method, the laser components, which need to be optimized for a further improvement of the laser contrast, can be identified. This will be essential for laser-matter interaction experiments requiring a minimized ASE intensity or fluence.

  9. An RF power amplifier with inter-metal-shuffled capacitor for inter-stage matching in a digital CMOS process

    Institute of Scientific and Technical Information of China (English)

    Feng Xiaoxing; Zhang Xing; Ge Binjie; Wang Xin'an

    2009-01-01

    One challenge of the implementation of fully-integrated RF power amplifiers into a deep submicro digital CMOS process is that no capacitor is available, especially no high density capacitor. To address this problem, a twostage class-AB power amplifier with inter-stage matching realized by an inter-metal coupling capacitor is designed in a 180-nm digital CMOS process. This paper compares three structures of inter-metal coupling capacitors with metal-insulator-metal (MIM) capacitor regarding their capacitor density. Detailed simulations are carried out for the leakage, the voltage dependency, the temperature dependency, and the quality factor between an inter-metal shuffled (IMS) capacitor and an MIM capacitor. Finally, an IMS capacitor is chosen to perform the inter-stage matching.The techniques are validated via the design and implement of a two-stage class-AB RF power amplifier for an UHF RFID application. The PA occupies 370 X 200 μm2 without pads in the 180-nm digital CMOS process and outputs 21.1 dBm with 40% drain efficiency and 28.1 dB power gain at 915 MHz from a single 3.3 V power supply.

  10. Energy-Efficient Power Allocation for Fixed-Gain Amplify-and-Forward Relay Networks with Partial Channel State Information

    KAUST Repository

    Zafar, Ammar

    2012-06-01

    In this report, energy-efficient transmission and power allocation for fixed-gain amplify-and-forward relay networks with partial channel state information (CSI) are studied. In the energy-efficiency problem, the total power consumed is minimized while keeping the signal-to-noise-ratio (SNR) above a certain threshold. In the dual problem of power allocation, the end-to-end SNR is maximized under individual and global power constraints. Closed-form expressions for the optimal source and relay powers and the Lagrangian multiplier are obtained. Numerical results show that the optimal power allocation with partial CSI provides comparable performance as optimal power allocation with full CSI at low SNR.

  11. Energy-Efficient Power Allocation for Fixed-Gain Amplify-and-Forward Relay Networks with Partial Channel State Information

    KAUST Repository

    Zafar, Ammar

    2012-09-16

    In this letter, energy-efficient transmission and power allocation for fixed-gain amplify-and-forward relay networks with partial channel state information (CSI) are studied. In the energy-efficiency problem, the total power consumed is minimized while keeping the signal-to-noise-ratio (SNR) above a certain threshold. In the dual problem of power allocation, the end-to-end SNR is maximized under individual and global power constraints. Closed-form expressions for the optimal source and relay powers and the Lagrangian multiplier are obtained. Numerical results show that the optimal power allocation with partial CSI provides comparable performance as optimal power allocation with full CSI at low SNR. © 2012 IEEE.

  12. A fast, low power and low noise charge sensitive amplifier ASIC for a UV imaging single photon detector

    Science.gov (United States)

    Seljak, A.; Cumming, H. S.; Varner, G.; Vallerga, J.; Raffanti, R.; Virta, V.

    2017-04-01

    NASA has funded, through their Strategic Astrophysics Technology (SAT) program, the development of a cross strip (XS) microchannel plate (MCP) detector with the intention to increase its technology readiness level (TRL), enabling prototyping for future NASA missions. One aspect of the development is to convert the large and high powered laboratory Parallel Cross Strip (PXS) readout electronics into application specific integrated circuits (ASICs) to decrease their mass, volume, and power consumption (all limited resources in space) and to make them more robust to the environments of rocket launch and space. The redesign also foresees to increase the overall readout event rate, and decrease the noise contribution of the readout system. This work presents the design and verification of the first stage for the new readout system, the 16 channel charge sensitive amplifier ASIC, called the CSAv3. The single channel amplifier is composed of a charge sensitive amplifier (pre-amplifier), a pole zero cancellation circuit and a shaping amplifier. An additional output stage buffer allows polarity selection of the output analog signal. The operation of the amplifier is programmable via serial bus. It provides an equivalent noise charge (ENC) of around 600 e^- and a baseline gain of 10 mV/fC. The full scale pulse shaped output signal is confined within 100 ns, without long recovery tails, enabling up to 10 MHz periodic event rates without signal pile up. This ASIC was designed and fabricated in 130 nm, TSMC CMOS 1.2 V technology. In addition, we briefly discuss the construction of the readout system and plans for the future work.

  13. Monolithic solid oxide fuel cell technology advancement for coal-based power generation. Quarterly technical status report, January--March 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-14

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  14. Decomposition of piecewise-polynomial model of a predistorter for power amplifier

    OpenAIRE

    2015-01-01

    Decomposition of piecewise-polynomial model of a predistorter has been performed taking into account the alteration dynamics of the complex envelope’s magnitude for the signal, which is converted by an amplifier. Decomposition model provides higher accuracy of nonlinear distortions compensation for signals in the amplifier compared with piecewise-polynomial model of a predistorter. Comparative analysis of predistorters’ models has been carried out for the linearization of the Wiener–Hammerste...

  15. A low power and low distortion rail-to-rail input/output amplifier using constant current technique

    Science.gov (United States)

    Yan, Liu; Yiqiang, Zhao; Shilin, Zhang; Hongliang, Zhao

    2011-04-01

    A rail-to-rail amplifier with constant transconductance, intended for audio processing, is presented. The constant transconductance is obtained by a constant current technique based on the input differential pairs operating in the weak inversion region. MOSFETs working in the weak inversion region have the advantages of low power and low distortion. The proposed rail-to-rail amplifier, fabricated in a standard 0.35 μm CMOS process, occupies a core die area of 75 × 183 μm2. Measured results show that the maximum power consumption is 85.37 μW with a supply voltage of 3.3 V and the total harmonic distortion level is 1.2% at 2 kHz.

  16. High power resonant pumping of Tm-doped fiber amplifiers in core- and cladding-pumped configurations.

    Science.gov (United States)

    Creeden, Daniel; Johnson, Benjamin R; Rines, Glen A; Setzler, Scott D

    2014-11-17

    We have demonstrated ultra-high efficiency amplification in Tm-doped fiber with both core- and cladding-pumped configurations using a resonant tandem-pumping approach. These Tm-doped fiber amplifiers are pumped in-band with a 1908 nm Tm-doped fiber laser and operate at 1993 nm with >90% slope efficiency. In a core-pumped configuration, we have achieved 92.1% slope efficiency and 88.4% optical efficiency at 41 W output power. In a cladding-pumped configuration, we have achieved 123.1 W of output power with 90.4% optical efficiency and a 91.6% slope efficiency. We believe these are the highest optical efficiencies achieved in a Tm-doped fiber amplifier operating in the 2-micron spectral region.

  17. A low power and low distortion rail-to-rail input/output amplifier using constant current technique

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yan; Zhao Yiqiang; Zhang Shilin [School of Electronic Information Engineering, Tianjin University, Tianjin 300072 (China); Zhao Hongliang, E-mail: zhaoyq@tju.edu.cn [School of Physics, Liaoning University, Shenyang 110036 (China)

    2011-04-15

    A rail-to-rail amplifier with constant transconductance, intended for audio processing, is presented. The constant transconductance is obtained by a constant current technique based on the input differential pairs operating in the weak inversion region. MOSFETs working in the weak inversion region have the advantages of low power and low distortion. The proposed rail-to-rail amplifier, fabricated in a standard 0.35 {mu}m CMOS process, occupies a core die area of 75 x 183 {mu}m{sup 2}. Measured results show that the maximum power consumption is 85.37 {mu}W with a supply voltage of 3.3 V and the total harmonic distortion level is 1.2% at 2 kHz. (semiconductor integrated circuits)

  18. Low spectral modulation high-power output from a new AlGaAs superluminescent diode/optical amplifier structure

    Energy Technology Data Exchange (ETDEWEB)

    Alphonse, G.A.; Connolly, J.C.; Dinkel, N.A.; Palfrey, S.L.; Gilbert, D.B. (David Sarnoff Research Center, Princeton, New Jersey 08543-5300 (US))

    1989-11-27

    A double-heterojunction angled stripe AlGaAs device consisting of an index-guided ridge waveguide with gain-guided facet regions has produced cw output powers of 20 mW with less than 1% spectral modulation from a 300-{mu}m-long diode. These properties enable these devices to have important use in high-sensitivity fiber optic gyroscopes and as broadband traveling-wave optical amplifiers.

  19. BER and optimal power allocation for amplify-and-forward relaying using pilot-aided maximum likelihood estimation

    KAUST Repository

    Wang, Kezhi

    2014-10-01

    Bit error rate (BER) and outage probability for amplify-and-forward (AF) relaying systems with two different channel estimation methods, disintegrated channel estimation and cascaded channel estimation, using pilot-aided maximum likelihood method in slowly fading Rayleigh channels are derived. Based on the BERs, the optimal values of pilot power under the total transmitting power constraints at the source and the optimal values of pilot power under the total transmitting power constraints at the relay are obtained, separately. Moreover, the optimal power allocation between the pilot power at the source, the pilot power at the relay, the data power at the source and the data power at the relay are obtained when their total transmitting power is fixed. Numerical results show that the derived BER expressions match with the simulation results. They also show that the proposed systems with optimal power allocation outperform the conventional systems without power allocation under the same other conditions. In some cases, the gain could be as large as several dB\\'s in effective signal-to-noise ratio.

  20. A 1.2 V low-power OpAmp for integrated lock-in amplifiers

    Science.gov (United States)

    Valero, M. R.; Celma, S.; Medrano, N.; Calvo, B.; Gimeno, C.

    2013-05-01

    This paper presents a simple 1.2 V low-power rail-to-rail class AB operational amplifier (OpAmp) suitable for integrated lock-in amplifiers. The proposed OpAmp has been designed in a standard 0.18 μm CMOS technology. For a 1.2 V single supply and 68.6 μW power consumption, simulations shows a 81 dB open loop gain, 64° phase margin, 13 MHz unity gain frequency for a capacitive load of 10pF and 75 dB CMRR. Adaptive biasing provides 30.7 V/μs slew-rate for a 10 pF load. A compact and reliable lock-in amplifier (LIA) has been designed using the proposed circuit. The designed LIA has a power consumption of 135 μW and recovers signals up to 1 MHz with relative errors below 2.6 % for noise and interference signals of the same amplitude as the signal of interest.

  1. Improvement of out-of-band Behaviour in Switch-Mode Amplifiers and Power Supplies by their Modulation Topology

    DEFF Research Database (Denmark)

    Knott, Arnold

    2010-01-01

    the interference of power electronics circuits and telecommunication circuits is to stay away from the frequencies used for information transmission. Even though the electromagnetic spectrum is used without any exceptions, the situation can be optimized for audio applications. This is done by using switching......Switch-mode power electronics is disturbing other electronic circuits by emission of electromagnetic waves and signals. To allow transmission of information, a set of regulatory rules (electromagnetic compatibility (EMC)) were created to limit this disturbance. To fulfill those rules in power....... After a historical overview and description of interaction between power electronics and electromagnetic compatibility (chapter 1), the thesis will first show the impact of the high frequency signals on the audio performance of switch-mode audio power amplifiers (chapter 2). Therefore the work of others...

  2. Ultra High Power and Efficiency Space Traveling-Wave Tube Amplifier Power Combiner with Reduced Size and Mass for NASA Missions

    Science.gov (United States)

    Simons, Rainee N.; Wintucky, Edwin G.; Wilson, Jeffrey D.; Force, Dale A.

    2009-01-01

    In the 2008 International Microwave Symposium (IMS) Digest version of our paper, recent advances in high power and efficiency space traveling-wave tube amplifiers (TWTAs) for NASA s space-to-Earth communications are presented. The RF power and efficiency of a new K-Band amplifier are 40 W and 50 percent and that of a new Ka-Band amplifier are 200 W and 60 percent. An important figure-of-merit, which is defined as the ratio of the RF power output to the mass (W/kg) of a TWT, has improved by a factor of ten over the previous generation Ka-Band devices. In this extended paper, a high power, high efficiency Ka-band combiner for multiple TWTs, based on a novel hybrid magic-T waveguide circuit design, is presented. The measured combiner efficiency is as high as 90 percent. In addition, at the design frequency of 32.05 GHz, error-free uncoded BPSK/QPSK data transmission at 8 megabits per second (Mbps), which is typical for deep space communications is demonstrated. Furthermore, QPSK data transmission at 622 Mbps is demonstrated with a low bit error rate of 2.4x10(exp -8), which exceeds the deep space state-of-the-art data rate transmission capability by more than two orders of magnitude. A potential application of the TWT combiner is in deep space communication systems for planetary exploration requiring transmitter power on the order of a kilowatt or higher.

  3. High efficiency 600-mW pHEMT distributed power amplifier employing drain impedance tapering technique

    DEFF Research Database (Denmark)

    Narendra, Kumar; Anand, Lokesh; Pragash, Sangaran;

    2008-01-01

    4-stage distributed power amplifier (DPA) employing tapering the drain load networks to achieve high efficiency is reported. The active device with enhancement mode pHEMT (pseudomorphic High Electron Mobility Transistor) technology is used. Measurement results of 600 mW, 30 % of power-aided-effic......-aided-efficiency (PAE) and gain of 10 dB is achieved within frequency range of 10–1800 MHz. Low supply voltage of 4.5 V is used for each device. Good agreement between measured and simulated results is obtained....

  4. High efficiency 600-mW pHEMT distributed power amplifier employing drain impedance tapering technique

    DEFF Research Database (Denmark)

    Narendra, Kumar; Anand, Lokesh; Pragash, Sangaran

    2008-01-01

    4-stage distributed power amplifier (DPA) employing tapering the drain load networks to achieve high efficiency is reported. The active device with enhancement mode pHEMT (pseudomorphic High Electron Mobility Transistor) technology is used. Measurement results of 600 mW, 30 % of power-aided-efficiency...... (PAE) and gain of 10 dB is achieved within frequency range of 10–1800 MHz. Low supply voltage of 4.5 V is used for each device. Good agreement between measured and simulated results is obtained....

  5. Low-Power Three-Stage Amplifier Using Active-Feedback Miller Capacitor and Serial RC Frequency Compensation

    Institute of Scientific and Technical Information of China (English)

    张庚宇; 肖夏; 聂凯明; 徐江涛

    2015-01-01

    A low-power three-stage amplifier for driving large capacitive load is proposed. The feedback path formed by the active-feedback Miller capacitor leads to a high frequency complex-pole but a highQ-value, which significantly deteriorates the stability of the amplifier. The serial RC stage introduced as the second stage output load can optimize the resistorRz and the capacitorCz under fixed power and small compensation capacitorCa, which brings about a suitableQ-value of the complex-pole and the gain-bandwidth product extension of the ampli-fier. The amplifiers were designed and implemented in a standard 65 nm CMOS process with capacitive loads of 500 pF and 2 nF, respectively. The post-layout simulation results show that the amplifier driving the 500 pF capaci-tive load can achieve a gain of 113 dB, a phase margin of 50.6° and a gain-bandwidth product of 5.22 MHz while consuming 24 µW from a 1.2 V supply. For the 2 nF capacitive load, the amplifier has a gain of 102 dB, a phase margin of 52.8°, a gain-bandwidth product of 4.41 MHz and a power of 43 µW. The total compensation capacitors are equal to 1.13 pF and 1.03 pF. The better figures-of-merits are 108 750 and 205 113(MHz×pF/mW). The lay-out areas are 0.064 mm×0.026 mm and 0.063 mm×0.027 mm. Compared with the CFCC scheme, the gain-bandwidth product is extended by 1.6 times atCL=500 pF andCa=1.1 pF.

  6. High SBS-Threshold Er/Yb Co-Doped Phosphate Glass Fiber Amplifiers for High Power, Sub-us Pulsed, Narrow Linewidth, All Fiber-Based Laser Transmitter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In order to implement the monolithic high power narrow linewidth pulsed all fiber-based laser transmitter by using a MOPA configuration for NASA's active remote...

  7. High SBS-Threshold Er/Yb Co-Doped Phosphate Glass Fiber Amplifiers for High Power, Sub-us Pulsed, Narrow Linewidth, All Fiber-Based Laser Transmitter Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In Phase I, NP Photonics has achieved 1.2 kW peak power for 105 ns fiber laser pulses, and successfully demonstrated the feasibility to produce monolithic high SBS...

  8. Optimizing the pumping configuration for the power scaling of in-band pumped erbium doped fiber amplifiers.

    Science.gov (United States)

    Lim, Ee-Leong; Alam, Shaif-ul; Richardson, David J

    2012-06-18

    A highly efficient (~80%), high power (18.45 W) in-band, core pumped erbium/ytterbium co-doped fiber laser is demonstrated. To the best of our knowledge, this is the highest reported efficiency from an in-band pumped 1.5 µm fiber laser operating in the tens of watts regime. Using a fitted simulation model, we show that the significantly sub-quantum limit conversion efficiency of in-band pumped erbium doped fiber amplifiers observed experimentally can be explained by concentration quenching. We then numerically study and experimentally validate the optimum pumping configuration for power scaling of in-band, cladding pumped erbium doped fiber amplifiers. Our simulation results indicate that a ~77% power conversion efficiency with high output power should be possible through cladding pumping of current commercially available pure Erbium doped active fibers providing the loss experienced by the cladding guided 1535 nm pump due to the coating absorption can be reduced to an acceptable level by better coating material choice. The power conversion efficiency has the potential to exceed 90% if concentration quenching of erbium ions can be reduced via improvements in fiber design and fabrication.

  9. High power 888 nm optical fiber end-pumped Nd:YVO4 picosecond regenerative amplifier at hundreds kHz

    Science.gov (United States)

    Bai, Zhenao; Fan, Zhongwei; Lian, Fuqiang; Tan, Tan; Bai, Zhenxu; Yang, Chao; Kang, Zhijun; Liu, Chang

    2016-10-01

    This paper describes a demonstration of a high power 888 nm end-pumped Nd:YVO4 picosecond regenerative amplifier operated at high repetition rate. By utilizing an all-fiber mode-locking picosecond laser as seed source and 888 nm continuous wave (CW) as pumping source, we obtained regenerative amplified output at 1064.07 nm with spectrum width 0.16 nm, pulse width of 38 ps, maximum power of 21 W, and the repetition rate is continuously adjustable from 300 to 500 kHz. The regenerative amplifier has high power stability and high compact structure.

  10. Practical Implementation and Error Analysis of PSCPWM-Based Switching Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Christensen, Frank Schwartz; Frederiksen, Thomas Mansachs; Andersen, Michael Andreas E.

    1999-01-01

    The paper presents an in-depth analysis of practical results for Parallel Phase-Shifted Carrier Pulse-Width Modulation (PSCPWM) - amplifier. Spectral analyses of error sources involved in PSCPWM are presented. The analysis is performed both by numerical means in MATLAB and by simulation in PSPICE...

  11. 500 MW peak power degenerated optical parametric amplifier delivering 52 fs pulses at 97 kHz repetition rate.

    Science.gov (United States)

    Rothhardt, J; Hädrich, S; Röser, F; Limpert, J; Tünnermann, A

    2008-06-09

    We present a high peak power degenerated parametric amplifier operating at 1030 nm and 97 kHz repetition rate. Pulses of a state-of-the art fiber chirped-pulse amplification (FCPA) system with 840 fs pulse duration and 410 microJ pulse energy are used as pump and seed source for a two stage optical parametric amplifier. Additional spectral broadening of the seed signal in a photonic crystal fiber creates enough bandwidth for ultrashort pulse generation. Subsequent amplification of the broadband seed signal in two 1 mm BBO crystals results in 41 microJ output pulse energy. Compression in a SF 11 prism compressor yields 37 microJ pulses as short as 52 fs. Thus, pulse shortening of more than one order of magnitude is achieved. Further scaling in terms of average power and pulse energy seems possible and will be discussed, since both concepts involved, the fiber laser and the parametric amplifier have the reputation to be immune against thermo-optical effects.

  12. Design and analysis of high-power segmented-core trench-assisted Yb-free erbium doped fiber amplifier

    Science.gov (United States)

    Gaur, Ankita; Rastogi, Vipul

    2017-10-01

    Limited power handling capacity of single mode fiber compels to design effective-single mode large-core fiber for high power amplifiers. This article proposes a 0.15 NA, large-mode-area, bend-insensitive, Yb-free EDFA for the selective amplification of fundamental mode. The fiber uses a leaky design to ensure fundamental-mode amplification by higher-order mode discrimination. The segmented-core design in the fiber helps in achieving large-mode-area. The annular segments and low index trench in the fiber control the leakage losses and gains of the modes. We show an EDFA design with 811 μm2 mode-area, 0.014 dB bending loss for 10 mm diameter loop at 1530 nm wavelength and highly selective single-mode output. Our calculations also show a linear increase in the output signal power with pump power with a slope efficiency of 52.8%.

  13. UHF power amplifier design in 0.35μm SiGe BiCMOS

    Institute of Scientific and Technical Information of China (English)

    Song Jiayou; Li Zhiqun; Wang Zhigon

    2009-01-01

    A two-stage power amplifier operated at 925 MHz was designed and fabricated in Jazz's 0.35μm SiGe BiCMOS process. It was fully integrated excluding the inductors and the output matching network. Under a single 3.3V supply voltage, the off-chip bonding test results indicated that the circuit has a small signal gain of more than 24dB, the input and output reflectance are less than -24dB and -10dB, respectively, and the maximal output power is 23.5 dBm. At output power of 23.1 dBm, the PAE (power added efficiency) is 30.2%, the IMD2 and IMD3 are less than -32 dBc and -46 dBc, respectively. The chip size is 1.27mm×0.9mm.

  14. Characterization of a High-SpeedHigh-Power Semiconductor Master-Oscillator Power-Amplifier (MOPA) Laser as a Free-Space Transmitter

    Science.gov (United States)

    Wright, M. W.

    2000-04-01

    Semiconductor lasers offer promise as high-speed transmitters for free-space optical communication systems. This article examines the performance of a semiconductor laser system in a master-oscillator power-amplifier (MOPA) geometry developed through a Small Business Innovation Research (SBIR) contract with SDL, Inc. The compact thermo-electric cooler (TEC) packaged device is capable of 1-W output optical power at greater than 2-Gb/s data rates and a wavelength of 960 nm. In particular, we have investigated the effects of amplified spontaneous emission on the modulation extinction ratio and bit-error rate (BER) performance. BERs of up to 10^(-9) were possible at 1.4 Gb/s; however, the modulation extinction ratio was limited to 6 dB. Other key parameters for a free-space optical transmitter, such as the electrical-optical efficiency (24 percent) and beam quality, also were measured.

  15. Design and analysis of an integrated pulse modulated s-band power amplifier in gallium nitride process

    Energy Technology Data Exchange (ETDEWEB)

    Sedlock, Steve [Kansas State Univ., Manhattan, KS (United States)

    2012-01-01

    The design of power amplifiers in any semi-conductor process is not a trivia exercise and it is often encountered that the simulated solution is qualitatively different than the results obtained. Phenomena such as oscillation occurring either in-band or out of band and sometimes at subharmonic intervals, continuous spectrum noticed in some frequency bands, often referred to as chaos, and jumps and hysteresis effects can all be encountered and render a design useless. All of these problems might have been identified through a more rigorous approach to stability analysis. Designing for stability is probably the one area of amplifier design that receives the least amount of attention but incurs the most catastrophic of effects if it is not performed properly. Other parameters such as gain, power output, frequency response and even matching may suitable mitigation paths. But the lack of stability in an amplifier has no mitigating path. In addition to of loss of the design completely there are the increased production cycle costs, costs involved with investigating and resolving the problem and the costs involved with schedule slips or delays resulting from it. The Linville or Rollett stability criteria that many microwave engineers follow and rely exclusively on is not sufficient by itself to ensure a stable and robust design. It will be shown that the universal belief that unconditional stability is obtained through an analysis of the scattering matrix S to determine if 1 and |{Delta}{sub S}| < 1 is only part of the procedure and other tools must be used to validate the criteria. The research shown contributes to the state of the art by developing a more thorough stability design technique for designing amplifiers of any class, whether that be current mode or switch mode, than is currently undertaken with the goal of obtaining first pass design success.

  16. Ultra-Low-Voltage Low-Power Bulk-Driven Quasi-Floating-Gate Operational Transconductance Amplifier

    Directory of Open Access Journals (Sweden)

    Ziad Alsibai

    2014-01-01

    Full Text Available A new ultra-low-voltage (LV low-power (LP bulk-driven quasi-floating-gate (BD-QFG operational transconductance amplifier (OTA is presented in this paper. The proposed circuit is designed using 0.18 μm CMOS technology. A supply voltage of ±0.3 V and a quiescent bias current of 5 μA are used. The PSpice simulation result shows that the power consumption of the proposed BD-QFG OTA is 13.4 μW. Thus, the circuit is suitable for low-power applications. In order to confirm that the proposed BD-QFG OTA can be used in analog signal processing, a BD-QFG OTA-based diodeless precision rectifier is designed as an example application. This rectifier employs only two BD-QFG OTAs and consumes only 26.8 μW.

  17. Femtosecond pulses at 50-W average power from an Yb:YAG planar waveguide amplifier seeded by an Yb:KYW oscillator.

    Science.gov (United States)

    Leburn, Christopher G; Ramírez-Corral, Cristtel Y; Thomson, Ian J; Hall, Denis R; Baker, Howard J; Reid, Derryck T

    2012-07-30

    We report the demonstration of a high-power single-side-pumped Yb:YAG planar waveguide amplifier seeded by an Yb:KYW femtosecond laser. Five passes through the amplifier yielded 700-fs pulses with average powers of 50 W at 1030 nm. A numerical simulation of the amplifier implied values for the laser transition saturation intensity, the small-signal intensity gain coefficient and the gain bandwidth of 10.0 kW cm(-2), 1.6 cm(-1), and 3.7 nm respectively, and identified gain-narrowing as the dominant pulse-shaping mechanism.

  18. Theoretical and numerical treatment of modal instability in high-power core and cladding-pumped Raman fiber amplifiers.

    Science.gov (United States)

    Naderi, Shadi; Dajani, Iyad; Grosek, Jacob; Madden, Timothy

    2016-07-25

    Raman fiber lasers have been proposed as potential candidates for scaling beyond the power limitations imposed on near diffraction-limited rare-earth doped fiber lasers. One limitation is the modal instability (MI) and we explore the physics of this phenomenon in Raman fiber amplifiers (RFAs). By utilizing the conservation of number of photons and conservation of energy in the absence of loss, the 3 × 3 governing system of nonlinear equations describing the pump and the signal modal content are decoupled and solved analytically for cladding-pumped RFAs. By comparing the extracted signal at MI threshold for the same step index-fiber, it is found that the MI threshold is independent of the length of the amplifier or whether the amplifier is co-pumped or counter-pumped; dictated by the integrated heat load along the length of fiber. We extend our treatment to gain-tailored RFAs and show that this approach is of limited utility in suppressing MI. Finally, we formulate the physics of MI in core-pumped RFAs where both pump and signal interferences participate in writing the time-dependent index of refraction grating.

  19. Multicanonical evaluation of the tails of the probability density function of semiconductor optical amplifier output power fluctuations

    DEFF Research Database (Denmark)

    Tromborg, Bjarne; Reimer, Michael; Yevick, David

    2010-01-01

    This paper presents a multicanonical Monte Carlo method for simulating the tails of a pdf distribution of the filtered output power from a semiconductor optical amplifier down to values of the order of 10−40. The influence of memory effects on the pdf is examined in order to demonstrate the manner...... in which the calculated pdf approaches the true pdf with increasing integration time. The simulated pdf is shown to be in good agreement with a second order analytic expression for the pdf....

  20. Single-Frequency, Yb-Free, Resonantly Cladding-Pumped Large Mode Area Er Fiber Amplifier for Power Scaling

    Science.gov (United States)

    2008-07-25

    report results for a single-frequency SF resonantly cladding-pumped Yb-free large mode area LMA erbium-doped fiber amplifier EDFA with nearly 50...original demonstration of a SF resonantly cladding-pumped LMA EDFA . We obtained a diffraction-limited SF output of 9.3 W, which is also a record power...output obtained for resonantly cladding-pumped LMA EDFA . © 2008 American Institute of Physics. DOI: 10.1063/1.2964189 Recent advances in eye-safe 1.5

  1. High-Power Hybrid Mode-Locked External Cavity Semiconductor Laser Using Tapered Amplifier with Large Tunability

    Directory of Open Access Journals (Sweden)

    Andreas Schmitt-Sody

    2008-01-01

    Full Text Available We report on hybrid mode-locked laser operation of a tapered semiconductor amplifier in an external ring cavity, generating pulses as short as 0.5 ps at 88.1 MHz with an average power of 60 mW. The mode locking is achieved through a combination of a multiple quantum well saturable absorber (>10% modulation depth and an RF current modulation. This designed laser has 20 nm tuning bandwidth in continuous wave and 10 nm tuning bandwidth in mode locking around 786 nm center wavelength at constant temperature.

  2. High-power SiC MESFET using a dual p-buffer layer for an S-band power amplifier

    Institute of Scientific and Technical Information of China (English)

    Deng Xiao-Chuan; Sun He; Rao Cheng-Yuan; Zhang Bo

    2013-01-01

    A silicon carbide (SiC) based metal semiconductor field effect transistor (MESFET) is fabricated by using a standard SiC MESFET structure with the application of a dual p-buffer layer and a multi-recessed gate to the process for an S-band power amplifier.The lower doped upper-buffer layer serves to maintain the channel current,while the higher doped lowerbuffer layer is used to provide excellent electron confinement in the channel layer.A 20-mm gate periphery SiC MESFET biased at a drain voltage of 85 V demonstrates a pulsed wave saturated output power of 94 W,a linear gain of 11.7 dB,and a maximum power added efficiency of 24.3% at 3.4 GHz.These results are improved compared with those of the conventional single p-buffer MESFET fabricated in this work using the same process.A radio-frequency power output greater than 4.7 W/mm is achieved,showing the potential as a high-voltage operation device for high-power solid-state amplifier applications.

  3. Cross-differential amplifier

    Science.gov (United States)

    Hajimiri, Seyed-Ali (Inventor); Kee, Scott D. (Inventor); Aoki, Ichiro (Inventor)

    2013-01-01

    A cross-differential amplifier is provided. The cross-differential amplifier includes an inductor connected to a direct current power source at a first terminal. A first and second switch, such as transistors, are connected to the inductor at a second terminal. A first and second amplifier are connected at their supply terminals to the first and second switch. The first and second switches are operated to commutate the inductor between the amplifiers so as to provide an amplified signal while limiting the ripple voltage on the inductor and thus limiting the maximum voltage imposed across the amplifiers and switches.

  4. Gain variation induced by power transient in thulium-doped fiber amplifier at 2 μm and its reduction by optical gain clamping technique

    Science.gov (United States)

    Khamis, M. A.; Ennser, K.

    2017-02-01

    This paper investigates the dynamic behavior of a thulium doped fiber amplifier (TDFA) operating in the 2 μm region for reconfigurable wavelength division multiplexing (WDM) systems. We show deleterious channel power fluctuations may be generated by input power variation at the amplifier and we propose the use of an optical gain-clamping technique. The investigated system consists of 20 channels with -4 dBm total input power. Our findings revealed that the effects of power transients due to channel reconfigurations are significantly reduced by a lasing feedback signal. Simulation results show that a power excursion of 4.3 dB is produced after dropping 19 channels when the amplifier gain is unclamped and only 0.0062 dB when the amplifier gain is clamped. The dynamics of GC-TDFA are mainly influenced by the value of the pump power factor and thus the laser signal achieves a stronger stabilization condition with increasing pump power factor. Hence, optical gain clamping is a simple and robust technique to control the power transient in the thulium-doped fiber amplifier of WDM systems at 2 μm.

  5. Monolithic microwave integrated circuits for sensors, radar, and communications systems; Proceedings of the Meeting, Orlando, FL, Apr. 2-4, 1991

    Science.gov (United States)

    Leonard, Regis F. (Editor); Bhasin, Kul B. (Editor)

    1991-01-01

    Consideration is given to MMICs for airborne phased arrays, monolithic GaAs integrated circuit millimeter wave imaging sensors, accurate design of multiport low-noise MMICs up to 20 GHz, an ultralinear low-noise amplifier technology for space communications, variable-gain MMIC module for space applications, a high-efficiency dual-band power amplifier for radar applications, a high-density circuit approach for low-cost MMIC circuits, coplanar SIMMWIC circuits, recent advances in monolithic phased arrays, and system-level integrated circuit development for phased-array antenna applications. Consideration is also given to performance enhancement in future communications satellites with MMIC technology insertion, application of Ka-band MMIC technology for an Orbiter/ACTS communications experiment, a space-based millimeter wave debris tracking radar, low-noise high-yield octave-band feedback amplifiers to 20 GHz, quasi-optical MESFET VCOs, and a high-dynamic-range mixer using novel balun structure.

  6. A Monolithic Double-balanced Upconverter for millimeter-wave Point-to-Multipoint Distribution Systems

    OpenAIRE

    Ang, K S; Robertson, I.D.

    2000-01-01

    The design and performance of a monolithic double-balanced upconverter for mm-wave point-to- multipoint distribution systems are presented. Individual building blocks including the LO /RF balun, IF balun,LO /RF power amplifier,and the double- balanced mixer are also fabricated and tested.The complete upconverter,measuring 3x3.2mm,upconverts the 3 -5GHz IF to 40.5 -43.5GHz band with 20 dBm output power.

  7. 一种新研制的W频段固态GaN功率放大器毫米波源%A Newly-developed W-band Solid-state GaN Power Amplifier Millimeter Wave Source

    Institute of Scientific and Technical Information of China (English)

    梁勤金; 石小燕; 潘文武; 黄吉金

    2016-01-01

    This paper introduces a newly-developed W-band solid-state GaN power amplifier millimeter wave(MMW) source,gives its system composition and operational principle,and provides the basic per-formance and experimental results of primary components including W-band solid-state Gunn driving source,W-band guide-microstrip line transposition and main amplifier chip. The MMW source operates at 94 GHz,its continuous wave power output is larger than 300 mW,linear gain is 10 dB,power-added effi-ciency( PAE) is greater than 16%. During the development of W-band solid-state MMW source, the choice of its monolithic microwave integrated circuit( MMIC) power amplifier of semiconductor material has undergone GaN,GaAs and InP,which clearly demonstrates that the output power,gain,efficiency and high temperature performance of W-band GaN MMIC power amplifier is superior to that of other solid-state MMIC power amplifiers. The high power technology of W-band solid-state GaN MMIC is likely to result in new revolutionized technology and application in the MMW field.%介绍了一种新研制的W频段固态GaN功率放大器毫米波源,给出了系统组成与工作原理,提供了其主要部件W频段固态Gunn驱动源、W频段波导-微带转换器、主放大器芯片基本性能及实验测试结果。该固态毫米波源工作频率94 GHz,输出连续波功率大于300 mW,线性增益10 dB,附加效率(PAE)大于16%。在W频段固态毫米波源研制过程中,其单片微波集成电路(MMIC)功率放大器半导体材料选择经历了GaAs、InP到GaN演变,结果清楚表明, W频段毫米波源的GaN MMlC功率放大器输出功率、增益、效率、高温性能要优于其他固态MMIC功率放大器性能。 W频段大功率固态GaN MMlC技术将在毫米波领域带来新的技术革命和应用。

  8. Nonlinear instabilities induced by the F coil power amplifier at FTU: Modeling and control

    Energy Technology Data Exchange (ETDEWEB)

    Zaccarian, L. [Dip. di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Via del Politecnico 1 - 00133 Roma (Italy); Boncagni, L. [Associazione Euratom/ENEA sulla fusione, Centro Ricerche Frascati, CP 65 - 00044 Frascati (Roma) (Italy); Cascone, D. [Dip. di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Via del Politecnico 1 - 00133 Roma (Italy); Centioli, C. [Associazione Euratom/ENEA sulla fusione, Centro Ricerche Frascati, CP 65 - 00044 Frascati (Roma) (Italy); Cerino, S. [Dip. di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Via del Politecnico 1 - 00133 Roma (Italy); Gravanti, F.; Iannone, F. [Associazione Euratom/ENEA sulla fusione, Centro Ricerche Frascati, CP 65 - 00044 Frascati (Roma) (Italy); Mecocci, F.; Pangione, L. [Dip. di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Via del Politecnico 1 - 00133 Roma (Italy); Podda, S. [Associazione Euratom/ENEA sulla fusione, Centro Ricerche Frascati, CP 65 - 00044 Frascati (Roma) (Italy); Vitale, V. [Associazione Euratom/ENEA sulla fusione, Centro Ricerche Frascati, CP 65 - 00044 Frascati (Roma) (Italy)], E-mail: vitale@frascati.enea.it; Vitelli, R. [Dip. di Informatica, Sistemi e Produzione, Universita di Roma, Tor Vergata, Via del Politecnico 1 - 00133 Roma (Italy)

    2009-06-15

    In this paper we focus on the instabilities caused by the nonlinear behavior of the F coil current amplifier at FTU. This behavior induces closed-loop instability of the horizontal position stabilizing loop whenever the requested current is below the circulating current level. In the paper we first illustrate a modeling phase where nonlinear dynamics are derived and identified to reproduce the open-loop responses measured by the F coil current amplifier. The derived model is shown to successfully reproduce the experimental behavior by direct comparison with experimental data. Based on this dynamic model, we then reproduce the closed-loop scenario of the experiment and show that the proposed nonlinear model successfully reproduces the nonlinear instabilities experienced in the experimental sessions. Given the simulation setup, we next propose a nonlinear control solution to this instability problem. The proposed solution is shown to recover stability in closed-loop simulations. Experimental tests are scheduled for the next experimental campaign after the FTU restart.

  9. Generation of 130 W narrow-linewidth high-peak-power picosecond pulses directly from a compact Yb-doped single-stage fiber amplifier

    Science.gov (United States)

    Qi, Yaoyao; Yu, Haijuan; Zhang, Jingyuan; Wang, Lei; Zhang, Ling; Lin, Xuechun

    2015-09-01

    We report a compact, 130-W single-stage master oscillator power amplifier with a high peak power of 51.3 kW and a narrow spectral linewidth of 0.1 nm. The seed source is a single-mode, passively mode-locked solid-state laser at 1064 nm with an average power of 2 W. At a repetition rate of 73.5 MHz, the pulse duration is 30 ps. After amplification, it stretches to 34.5 ps. The experiment enables the optical-to-optical conversion efficiency to reach 75%. To the best of our knowledge, this is the first report of such a high-power, narrow spectral linewidth, high peak power picosecond-pulse fiber amplifier based on a continuous-wave, mode-locked solid-state seeding laser. No amplified spontaneous emission and stimulated Raman scattering were observed when the pump was increased.

  10. 1.8V Operation Power Amplifier IC for Bluetooth Class 1 Utilizing p+-GaAs Gate Hetero-Junction FET

    Science.gov (United States)

    Harima, Fumio; Bito, Yasunori; Takahashi, Hidemasa; Iwata, Naotaka

    We have developed a power amplifier IC for Bluetooth Class 1 operating at single low voltage of 1.8V for both control and drain voltages. We can realize it due to fully enhancement-mode hetero-junction FETs utilizing a re-grown p+-GaAs gate technology. The power amplifier is a highly compact design as a small package of 1.5mm×1.5mm×0.4mm with fully integrated gain control and shutdown functions. An impressive power added efficiency of 52% at an output power of 20dBm is achieved with an associated gain of 22dB. Also, sufficiently low leakage current of 0.25μA at 27°C is exhibited, which is comparable to conventional HBT power amplifiers.

  11. A compact diode-pumped pulsed Nd:YAG slab laser based on a master oscillator power amplifier configuration

    Science.gov (United States)

    Maleki, A.; Kavosh Tehrani, M.; Saghafifar, H.; Moghtader Dindarlu, M. H.; Ebadian, H.

    2016-02-01

    In this paper, the design and construction of a pulsed Nd:YAG laser is described. The structure of this laser is based on a master oscillator power amplifier system. A master oscillator is an electro-optical Q-switched Nd:YAG rod laser. Face-pumping is used for the excitation of the slab structure, and a double-pass method is designed for the amplification stages. Two Nd:YAG zigzag slabs are utilized as power amplification stages in this laser. The laser diodes are stacked in a compact configuration and are used for rod and slabs pumping. The total pump energy in the amplifier stages is 3200 mJ at 808 nm. The output pulse energy achieved at 1064 nm is about 850 mJ of 10 ns pulse duration corresponding to 26.5% optical-to-optical conversion efficiency. Moreover, this laser can generate pulse energies around 430 mJ at 532 nm. The dependence of the output energy of MOPA and second harmonic generation operations on different pulse repetition rates (PRRs) from 1 to 100 Hz has been investigated. Experimental results show that the maximum fluctuations of the output energies are about 2.5 and 4% for 1064 and 532 nm, respectively.

  12. BTL音频功率放大电路教学研讨%Teaching research on BTL audio power amplifier

    Institute of Scientific and Technical Information of China (English)

    曹钟林

    2015-01-01

    In the course of 《Analog Electronic Technology》in higher vocational colleges, the OCL and OTL audio power amplifier circuit is more and more widely used, and the BTL (Transformer Less Balanced balanced output transformer) audio power amplifier circuit is often omitted. The advantages of BTL circuit and OTL circuit are obvious, and it should be given some attention. This paper analysis the structure, principle and design method of BTL circuit from the perspective of teaching.%在高职院校的《模拟电子技术》课程中,OCL和OTL音频功率放大电路讲解的较多,而应用较为广泛的BTL ( Balanced Transformer Less平衡无输出变压器)音频功率放大电路往往略讲, BTL电路较OCL和OTL电路优点是显而易见的,应当给予一定的关注。本文从教学的角度解析BTL电路的结构、原理及设计制作思路。

  13. Coupling of symmetric and asymmetric modes in a high-power, high-efficiency traveling-wave amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Banna, S. [Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, (Israel); Schaechter, L. [Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, (Israel); Nation, J. A. [School of Electrical Engineering and Laboratory of Plasma Studies, Cornell University Ithaca, New York 14853 (United States); Wang, P. [School of Electrical Engineering and Laboratory of Plasma Studies, Cornell University Ithaca, New York 14853 (United States)

    2000-04-01

    A three-dimensional model has been developed for the investigation of the coupling of symmetric (TM{sub 01}) and asymmetric (HEM{sub 11}) modes in a high-power, high-efficiency traveling-wave amplifier. In the framework of a simplified model it is shown that the coupling between these two modes is determined by a single parameter that depends on the beam characteristics. For a specific set of parameters corresponding to operation at 35 GHz, simulations indicate that an initial HEM{sub 11} power of 0.5 MW at the input end is sufficient to deflect electrons to the wall. The build-up of this parasitic mode is investigated over many round trips of the wave in the structure and a threshold criterion for self-sustain oscillation is established. Finally a way for suppressing the HEM{sub 11} mode is analyzed. (c) 2000 The American Physical Society.

  14. Monolithic Lumped Element Integrated Circuit (M2LEIC) Transistors.

    Science.gov (United States)

    INTEGRATED CIRCUITS, *MONOLITHIC STRUCTURES(ELECTRONICS), *TRANSISTORS, CHIPS(ELECTRONICS), FABRICATION, EPITAXIAL GROWTH, ULTRAHIGH FREQUENCY, POLYSILICONS, PHOTOLITHOGRAPHY, RADIOFREQUENCY POWER, IMPEDANCE MATCHING .

  15. On-chip power-combining techniques for watt-level linear power amplifiers in 0.18 μm CMOS

    Science.gov (United States)

    Zhixiong, Ren; Kefeng, Zhang; Lanqi, Liu; Cong, Li; Xiaofei, Chen; Dongsheng, Liu; Zhenglin, Liu; Xuecheng, Zou

    2015-09-01

    Three linear CMOS power amplifiers (PAs) with high output power (more than watt-level output power) for high data-rate mobile applications are introduced. To realize watt-level output power, there are two 2.4 GHz PAs using an on-chip parallel combining transformer (PCT) and one 1.95 GHz PA using an on-chip series combining transformer (SCT) to combine output signals of multiple power stages. Furthermore, some linearization techniques including adaptive bias, diode linearizer, multi-gated transistors (MGTR) and the second harmonic control are applied in these PAs. Using the proposed power combiner, these three PAs are designed and fabricated in TSMC 0.18 μm RFCMOS process. According to the measurement results, the proposed two linear 2.4 GHz PAs achieve a gain of 33.2 dB and 34.3 dB, a maximum output power of 30.7 dBm and 29.4 dBm, with 29% and 31.3% of peak PAE, respectively. According to the simulation results, the presented linear 1.95 GHz PA achieves a gain of 37.5 dB, a maximum output power of 34.3 dBm with 36.3% of peak PAE. Project supported by the National Natural Science Foundation of China (No. 61076030).

  16. Second-order coherence properties of amplified spontaneous emission from a high-power tapered superluminescent diode

    Science.gov (United States)

    Kiethe, Jan; Heuer, Axel; Jechow, Andreas

    2017-08-01

    We study the degree of second-order coherence of the emission of a high-power multi-quantum well superluminescent diode with a lateral tapered amplifier section with and without optical feedback. When operated in an external cavity, the degree of second-order coherence changed from the almost thermal case of g(2)(0)≈1.9 towards the mostly coherent case of g(2)(0)≈1.2 when the injection current at the tapered section was increased. We found good agreement with semi-classical laser theory near and below threshold while above laser threshold a slightly higher g (2)(0) was observed. As a free running device, the superluminescent diode yielded more than 400 mW of optical output power with good spatial beam quality of M^2_slow < 1.6 . In this case, the degree of second-order coherence dropped only slightly from 1.9 at low powers to 1.6 at the maximum output power. To our knowledge, this is the first investigation of a high-power tapered superluminescent diode concerning the degree of second-order coherence. Such a device might be useful for real-world applications probing the second order coherence function, such as ghost imaging.

  17. Droop-Free, Reliable, and High-Power InGaN/GaN Nanowire Light-Emitting Diodes for Monolithic Metal-Optoelectronics

    KAUST Repository

    Zhao, Chao

    2016-07-28

    A droop-free nitride light-emitting diode (LED) with the capacity to operate beyond the “green gap” has been a subject of intense scientific and engineering interest. While several properties of nanowires on silicon make them promising for use in LED development, the high aspect ratio of individual nanowires and their laterally discontinuous features limit phonon transport and device performance. Here, we report on the monolithic integration of metal heat-sink and droop-free InGaN/GaN quantum-disks-in-nanowire LEDs emitting at ∼710 nm. The reliable operation of our uncooled nanowire-LEDs (NW-LEDs) epitaxially grown on molybdenum was evident in the constant-current soft burn-in performed on a 380 μm × 380 μm LED. The square LED sustained 600 mA electrical stress over an 8 h period, providing stable light output at maturity without catastrophic failure. The absence of carrier and phonon transport barriers in NW-LEDs was further inferred from current-dependent Raman measurements (up to 700 mA), which revealed the low self-heating. The radiative recombination rates of NW-LEDs between room temperature and 40 °C was not limited by Shockley–Read–Hall recombination, Auger recombination, or carrier leakage mechanisms, thus realizing droop-free operation. The discovery of reliable, droop-free devices constitutes significant progress toward the development of nanowires for practical applications. Our monolithic approach realized a high-performance device that will revolutionize the way high power, low-junction-temperature LED lamps are manufactured for solid-state lighting and for applications in high-temperature harsh environment.

  18. Low-power priority Address-Encoder and Reset-Decoder data-driven readout for Monolithic Active Pixel Sensors for tracker system

    Energy Technology Data Exchange (ETDEWEB)

    Yang, P., E-mail: yangping0710@126.com [Central China Normal University, Wuhan (China); Aglieri, G.; Cavicchioli, C. [CERN, 1210 Geneva 23 (Switzerland); Chalmet, P.L. [MIND, Archamps (France); Chanlek, N. [Suranaree University of Technology, Nakhon Ratchasima (Thailand); Collu, A. [University of Cagliari, Cagliari (Italy); INFN (Italy); Gao, C. [Central China Normal University, Wuhan (China); Hillemanns, H.; Junique, A. [CERN, 1210 Geneva 23 (Switzerland); Kofarago, M. [CERN, 1210 Geneva 23 (Switzerland); University of Utrecht, Utrecht (Netherlands); Keil, M.; Kugathasan, T. [CERN, 1210 Geneva 23 (Switzerland); Kim, D. [Dongguk and Yonsei University, Seoul (Korea, Republic of); Kim, J. [Pusan National University, Busan (Korea, Republic of); Lattuca, A. [University of Torino, Torino (Italy); INFN (Italy); Marin Tobon, C.A. [CERN, 1210 Geneva 23 (Switzerland); Marras, D. [University of Cagliari, Cagliari (Italy); INFN (Italy); Mager, M.; Martinengo, P. [CERN, 1210 Geneva 23 (Switzerland); Mazza, G. [University of Torino, Torino (Italy); INFN (Italy); and others

    2015-06-11

    Active Pixel Sensors used in High Energy Particle Physics require low power consumption to reduce the detector material budget, low integration time to reduce the possibilities of pile-up and fast readout to improve the detector data capability. To satisfy these requirements, a novel Address-Encoder and Reset-Decoder (AERD) asynchronous circuit for a fast readout of a pixel matrix has been developed. The AERD data-driven readout architecture operates the address encoding and reset decoding based on an arbitration tree, and allows us to readout only the hit pixels. Compared to the traditional readout structure of the rolling shutter scheme in Monolithic Active Pixel Sensors (MAPS), AERD can achieve a low readout time and a low power consumption especially for low hit occupancies. The readout is controlled at the chip periphery with a signal synchronous with the clock, allows a good digital and analogue signal separation in the matrix and a reduction of the power consumption. The AERD circuit has been implemented in the TowerJazz 180 nm CMOS Imaging Sensor (CIS) process with full complementary CMOS logic in the pixel. It works at 10 MHz with a matrix height of 15 mm. The energy consumed to read out one pixel is around 72 pJ. A scheme to boost the readout speed to 40 MHz is also discussed. The sensor chip equipped with AERD has been produced and characterised. Test results including electrical beam measurement are presented.

  19. Regime dependence of photo-darkening-induced modal degradation in high power fiber amplifier (Conference Presentation)

    Science.gov (United States)

    Boullet, Johan; Vincont, Cyril; Jolly, Alain; Pierre, Christophe

    2017-03-01

    Thermally induced transverse modal instabilities (TMI) have attracted these five years an intense research efforts of the entire fiber laser development community, as it represents the current most limiting effect of further power scaling of high power fiber laser. Anyway, since 2014, a few publications point out a new limiting thermal effect: fiber modal degradation (FMD). It is characterized by a power rollover and simultaneous increase of the cladding light at an average power far from the TMI threshold together with a degraded beam which does not exhibit temporal fluctuations, which is one of the main characteristic of TMI. We report here on the first systemic experimental study of FMD in a high power photonic crystal fiber. We put a particular emphasis on the dependence of its average power threshold on the regime of operation. We experimentally demonstrate that this dependence is intrinsically linked to regime-dependent PD-saturated losses, which are nearly three times higher in CW regime than in short pulse picosecond regime. We make the hypothesis that the existence of these different PD equilibrium states between CW regime and picosecond QCW pulsed regime is due to a partial photo-bleaching of color centers in picosecond regime thanks to a higher probability of multi-photon process induced photobleaching (PB) at high peak power. This hypothesis is corroborated by the demonstration of the reversibility of the FMD induced in CW regime by simply switching the seed CW 1064 nm light by a short pulse, picosecond oscillator.

  20. Nanosecond monolithic CMOS readout cell

    Science.gov (United States)

    Souchkov, Vitali V.

    2004-08-24

    A pulse shaper is implemented in monolithic CMOS with a delay unit formed of a unity gain buffer. The shaper is formed of a difference amplifier having one input connected directly to an input signal and a second input connected to a delayed input signal through the buffer. An elementary cell is based on the pulse shaper and a timing circuit which gates the output of an integrator connected to the pulse shaper output. A detector readout system is formed of a plurality of elementary cells, each connected to a pixel of a pixel array, or to a microstrip of a plurality of microstrips, or to a detector segment.

  1. Monoliths in Bioprocess Technology

    Directory of Open Access Journals (Sweden)

    Vignesh Rajamanickam

    2015-04-01

    Full Text Available Monolithic columns are a special type of chromatography column, which can be used for the purification of different biomolecules. They have become popular due to their high mass transfer properties and short purification times. Several articles have already discussed monolith manufacturing, as well as monolith characteristics. In contrast, this review focuses on the applied aspect of monoliths and discusses the most relevant biomolecules that can be successfully purified by them. We describe success stories for viruses, nucleic acids and proteins and compare them to conventional purification methods. Furthermore, the advantages of monolithic columns over particle-based resins, as well as the limitations of monoliths are discussed. With a compilation of commercially available monolithic columns, this review aims at serving as a ‘yellow pages’ for bioprocess engineers who face the challenge of purifying a certain biomolecule using monoliths.

  2. Derivation and Analysis of a Low-Cost, High-performance Analogue BPCM Control Scheme for Class-D Audio Power Amplifiers

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.

    2005-01-01

    This paper presents a low-cost analogue control scheme for class-D audio power amplifiers. The scheme is based around bandpass current-mode (BPCM) control, and provides ample stability margins and low distortion over a wide range of operating conditions. Implementation is very simple and does...... not require the use of operational amplifiers. Small-signal behavior of the controller is accurately predicted, and design is carried out using standard transfer function based linear control methodology. Effectiveness of the approach is demonstrated via a 60W/8Ω single-ended switching amplifier with THD...

  3. Design of low power common-gate low noise amplifier for 2.4 GHz wireless sensor network applications

    Institute of Scientific and Technical Information of China (English)

    Zhang Meng; Li Zhiqun

    2012-01-01

    This paper presents a differential low power low noise amplifier designed for the wireless sensor network (WSN) in a TSMC 0.18 μm RF CMOS process.A two-stage cross-coupling cascaded common-gate (CG)topology has been designed as the amplifier.The first stage is a capacitive cross-coupling topology.It can reduce the power and noise simultaneously.The second stage is a positive feedback cross-coupling topology,used to set up a negative resistance to enhance the equivalent Q factor of the inductor at the load to improve the gain of the LNA.A differential inductor has been designed as the load to achieve reasonable gain.This inductor has been simulated by the means of momentum electromagnetic simulation in ADS.A “double-π” circuit model has been built as the inductor model by iteration in ADS.The inductor has been fabricated separately to verify the model.The LNA has been fabricated and measured.The LNA works well centered at 2.44 GHz.The measured gain S21 is variable with high gain at 16.8 dB and low gain at 1 dB.The NF (noise figure) at high gain mode is 3.6 dB,the input referenced 1 dB compression point (IP1dB) is about-8 dBm and the IIP3 is 2 dBm at low gain mode.The LNA consumes about 1.2 mA current from 1.8 V power supply.

  4. High-power X- and Ka-band Gallium Nitride Amplifiers with Exceptional Efficiency Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Achieving very high-power amplification with maximum efficiency at X- and Ka-band is challenging using solid-state technology. Gallium Arsenide (GaAs) has been the...

  5. Portable musical instrument amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Christian, David E. (Danbury, CT)

    1990-07-24

    The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.

  6. Twenty-watt average output power, picosecond thin-rod Yb:YAG regenerative chirped pulse amplifier with 200 mJ pulse energy

    OpenAIRE

    MATSUBARA, Shinichi; TANAKA, Motoharu; TAKAMA, Masaki; KAWATO, Sakae; Kobayashi, Takao

    2008-01-01

    A high-average power, laser-diode-pumped, picosecond-pulse regenerative chirpedpulse amplifier was developed by using the thin-rod Yb:YAG laser architecture. An averageoutput power of 20 W was achieved at a repetition rate of 100 kHz with an output pulse width of 2ps.

  7. CMOS工艺射频功率放大器的实现与验证%Realization and verification of the CMOS technology RF power amplifier

    Institute of Scientific and Technical Information of China (English)

    谢君

    2011-01-01

    RF power amplifiers are key components in wireless devices, CaAs technology is widely used in the design and manufacture of RF power amplifier. But the CMOS technology has the very big superiority in the production maturity and the cost, this paper focuses on the problems that using CMOS technology to do the RF power amplifier, introduces the world's first mass product CMOS power amplifier and the special techniques used. Using a mature handset product, it replaces this power amplifier and the peripheral components, and finally carries on the contrast test with the original product.%射频功率放大器是无线设备的关键器件,GaAs工艺被广泛使用在射频功放的设计制造上.而CMOS工艺在生产成熟度和成本上有很大优势,主要关注用CMOS工艺来做射频功放的问题,介绍世界上第一颗量产的CMOS功放及其所使用的特殊技术.利用一款成熟的手机产品,替换这颗功放及外围器件,最后与原产品进行对比测试.

  8. Fiber Amplifiers

    DEFF Research Database (Denmark)

    Rottwitt, Karsten

    2017-01-01

    The chapter provides a discussion of optical fiber amplifiers and through three sections provides a detailed treatment of three types of optical fiber amplifiers, erbium doped fiber amplifiers (EDFA), Raman amplifiers, and parametric amplifiers. Each section comprises the fundamentals including t...

  9. Monolithic microchannel heatsink

    Science.gov (United States)

    Benett, William J.; Beach, Raymond J.; Ciarlo, Dino R.

    1996-01-01

    A silicon wafer has slots sawn in it that allow diode laser bars to be mounted in contact with the silicon. Microchannels are etched into the back of the wafer to provide cooling of the diode bars. To facilitate getting the channels close to the diode bars, the channels are rotated from an angle perpendicular to the diode bars which allows increased penetration between the mounted diode bars. This invention enables the fabrication of monolithic silicon microchannel heatsinks for laser diodes. The heatsinks have low thermal resistance because of the close proximity of the microchannels to the laser diode being cooled. This allows high average power operation of two-dimensional laser diode arrays that have a high density of laser diode bars and therefore high optical power density.

  10. High Performance and Low power Monolithic Three-Dimensional Sub-50 nm Poly Si Thin film transistor (TFTs) Circuits.

    Science.gov (United States)

    Wu, Tsung-Ta; Huang, Wen-Hsien; Yang, Chih-Chao; Chen, Hung-Chun; Hsieh, Tung-Ying; Lin, Wei-Sheng; Kao, Ming-Hsuan; Chen, Chiu-Hao; Yao, Jie-Yi; Jian, Yi-Ling; Hsu, Chiung-Chih; Lin, Kun-Lin; Shen, Chang-Hong; Chueh, Yu-Lun; Shieh, Jia-Min

    2017-05-02

    Development of manufacture trend for TFTs technologies has focused on improving electrical properties of films with the cost reduction to achieve commercialization. To achieve this goal, high-performance sub-50 nm TFTs-based MOSFETs with ON-current (Ion)/subthreshold swing (S.S.) of 181 µA/µm/107 mV/dec and 188 µA/µm/98 mV/dec for NMOSFETs and PMOSFETs in a monolithic 3D circuit were demonstrated by a low power with low thermal budget process. In addition, a stackable static random access memory (SRAM) integrated with TFTs-based MOSFET with static noise margins (SNM) equals to 390 mV at VDD = 1.0 V was demonstrated. Overall processes include a low thermal budget via ultra-flat and ultra-thin poly-Si channels by solid state laser crystallization process, chemical-mechanical polishing (CMP) planarization, plasma-enhanced atomic layer deposition (ALD) gate stacking layers and infrared laser activation with a low thermal budget. Detailed material and electrical properties were investigated. The advanced 3D architecture with closely spaced inter-layer dielectrics (ILD) enables high-performance stackable MOSFETs and SRAM for power-saving IoT/mobile products at a low cost or flexible substrate.

  11. On the jamming power allocation for secure amplify-and-forward relaying via cooperative jamming

    KAUST Repository

    Park, Kihong

    2013-09-01

    In this paper, we investigate secure communications in two-hop wireless relaying networks with one eavesdropper. To prevent the eavesdropper from intercepting the source message, the destination sends an intended jamming noise to the relay, which is referred to as cooperative jamming. This jamming noise helps protecting the source message from being captured reliably at the eavesdropper, while the destination cancels its self-intended noise. According to the channel information available at the destination, we derive three jamming power allocation strategies to minimize the outage probability of the secrecy rate. In addition, we derive analytic results quantifying the jamming power consumption of the proposed allocation methods. © 1983-2012 IEEE.

  12. WCDMA outphasing power amplifier with a software defined transmitter/receiver architecture for determination of the predistortion function

    Directory of Open Access Journals (Sweden)

    W. Gerhard

    2006-01-01

    Full Text Available A flexible and easily configurable software defined transmitter/receiver (TX/RX architecture is described, which allows the determination of the distorted complex transfer characteristics of a 3 port nonlinear outphasing power amplifier (PA for application in a WCDMA base station. The TX/RX architecture is capable of generating high precision single sideband signals (SSB using a DSP algorithm, which is almost insensitive to measurement errors and to the frequency response of the output measurement channel. Based on this an inverse predistortion function for a necessary linearization is calculated and implemented into a FPGA (field programmable gate array through look-up-tables (LUT. The common base band and the differential phase angles are predistorted, resulting in a linearization of the PA.

  13. Investigation of crosstalk in self oscillating switch mode audio power amplifier

    DEFF Research Database (Denmark)

    Birch, Thomas Haagen; Ploug, Rasmus Overgaard; Iversen, Niels Elkjær

    2012-01-01

    channel self oscillating switch mode power amplier (class D). A step by step reduction of elements in an amplier built for this task, is used for methodically determining the actual presence and origins of crosstalk. The investigation shows that the crosstalk is caused by couplings in the self oscillating...

  14. Monolithic circuits for barium fluoride detectors used in nuclear physics experiments. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Varner, R.L.; Blankenship, J.L.; Beene, J.R. [Oak Ridge National Lab., TN (United States); Todd, R.A. [RIS Corp., Oak Ridge, TN (United States)

    1998-02-01

    Custom monolithic electronic circuits have been developed recently for large detector applications in high energy physics where subsystems require tens of thousands of channels of signal processing and data acquisition. In the design and construction of these enormous detectors, it has been found that monolithic circuits offer significant advantages over discrete implementations through increased performance, flexible packaging, lower power and reduced cost per channel. Much of the integrated circuit design for the high energy physics community is directly applicable to intermediate energy heavy-ion and electron physics. This STTR project conducted in collaboration with researchers at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory, sought to develop a new integrated circuit chip set for barium fluoride (BaF{sub 2}) detector arrays based upon existing CMOS monolithic circuit designs created for the high energy physics experiments. The work under the STTR Phase 1 demonstrated through the design, simulation, and testing of several prototype chips the feasibility of using custom CMOS integrated circuits for processing signals from BaF{sub 2} detectors. Function blocks including charge-sensitive amplifiers, comparators, one shots, time-to-amplitude converters, analog memory circuits and buffer amplifiers were implemented during Phase 1 effort. Experimental results from bench testing and laboratory testing with sources were documented.

  15. Dual-Polarized Antenna Arrays with CMOS Power Amplifiers for SiP Integration at W-Band

    Science.gov (United States)

    Giese, Malte; Vehring, Sönke; Böck, Georg; Jacob, Arne F.

    2017-08-01

    This paper presents requirements and front-end solutions for low-cost communication systems with data rates of 100 Gbit/s. Link budget analyses in different mass-market applications are conducted for that purpose. It proposes an implementation of the front-end as an active antenna array with support for beam steering and polarization multiplexing over the full W-band. The critical system components are investigated and presented. This applies to a transformer coupled power amplifier (PA) in 40 nm bulk CMOS. It shows saturated output power of more than 10 dBm and power-added-efficiency of more than 10 % over the full W-band. Furthermore, the performance of microstrip-to-waveguide transitions is shown exemplarily as an important part of the active antenna as it interfaces active circuitry and antenna in a polymer-and-metal process. The transition test design shows less than 0.9 dB insertion loss and more than 12 dB return loss for the differential transition over the full W-band.

  16. Power Allocation Strategies for Fixed-Gain Half-Duplex Amplify-and-Forward Relaying in Nakagami-m Fading

    KAUST Repository

    Zafar, Ammar

    2013-09-01

    In this paper, we study power allocation strategies for a fixed-gain amplify-and-forward relay network employing multiple relays. We consider two optimization problems for the relay network: 1) maximizing the end-to-end signalto- noise ratio (SNR) and 2) minimizing the total power consumption while maintaining the end-to-end SNR over a threshold value. We investigate these two problems for two relaying protocols of all-participate (AP) relaying and selective relaying and two cases of feedback to the relays, full and limited. We show that the SNR maximization problem is concave and the power minimization problem is convex for all protocols and feedback cases considered. We obtain closed-form expressions for the two problems in the case of full feedback and solve the problems through convex programming for limited feedback. Numerical results show the benefit of having full feedback at the relays for both optimization problems. However, they also show that feedback overhead can be reduced by having only limited feedback to the relays with only a small degradation in performance.

  17. Analysis of the third harmonic for class-F power amplifiers with an I-V knee effect

    Science.gov (United States)

    Zhao, Bo-Chao; Lu, Yang; Wei, Jia-Xing; Dong, Liang; Wang, Yi; Cao, Meng-Yi; Ma, Xiao-Hua; Hao, Yue

    2015-05-01

    The appearance of third-generation semiconductors represented by gallium nitride (GaN) material greatly improves the output power of a power amplifier (PA), but the efficiency of the PA needs to be further improved. The Class-F PA reduces the overlap of drain voltage and current by tuning harmonic impedance so that high efficiency is achieved. This paper begins with the principle of class-F PA, regards the third harmonic voltage as an independent variable, analyzes the influence of the third harmonic on fundamental, and points out how drain efficiency and output power vary with the third harmonic voltage with an I-V knee effect. Finally, the best third harmonic impedance is found mathematically. We compare our results with the Loadpull technique in advanced design system environment and conclude that an optimized third harmonic impedance is open in an ideal case, while it is not at an open point with the I-V knee effect, and the drain efficiency with optimized third harmonic impedance is 4% higher than that with the third harmonic open.

  18. Solid-state repetitive generator with a gyromagnetic nonlinear transmission line operating as a peak power amplifier

    Science.gov (United States)

    Gusev, A. I.; Pedos, M. S.; Rukin, S. N.; Timoshenkov, S. P.

    2017-07-01

    In this work, experiments were made in which gyromagnetic nonlinear transmission line (NLTL) operates as a peak power amplifier of the input pulse. At such an operating regime, the duration of the input pulse is close to the period of generated oscillations, and the main part of the input pulse energy is transmitted only to the first peak of the oscillations. Power amplification is achieved due to the voltage amplitude of the first peak across the NLTL output exceeding the voltage amplitude of the input pulse. In the experiments, the input pulse with an amplitude of 500 kV and a half-height pulse duration of 7 ns is applied to the NLTL with a natural oscillation frequency of ˜300 MHz. At the output of the NLTL in 40 Ω coaxial transmission line, the pulse amplitude is increased to 740 kV and the pulse duration is reduced to ˜2 ns, which correspond to power amplification of the input pulse from ˜6 to ˜13 GW. As a source of input pulses, a solid-state semiconductor opening switch generator was used, which allowed carrying out experiments at pulse repetition frequency up to 1 kHz in the burst mode of operation.

  19. Experimental results of a sheet-beam, high power, FEL amplifier with application to magnetic fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, S.; Destler, W.W.; Granatstein, V.L. [Univ. of Maryland, College Park, MD (United States)] [and others

    1995-12-31

    The experimental study of sheet-beam FELs as candidate millimeter-wave sources for heating magnetic fusion plasmas has achieved a major milestone. In a proof-of-principle, pulsed experiment, saturated FEL amplifier operation was achieved with 250 kW of output power at 86 GHz. Input microwave power was 1 kW, beam voltage was 450 kV and beam current was 17 A. The planar wiggler had a peak value of 3.8 kG, a period of 0.96 cm and was 71 cm long. The linear gain of 30 dB, saturated gain of 24 dB and saturated efficiency of 3% all are in good agreement with theoretical prediction. Follow-on work would include development of a thermionic sheet-beam electron-gun compatible with CW FEL operation, adding a section of tapered wiggler to increase the output power to levels in excess of 1 megawatt, and increasing the FEL frequency.

  20. Power Scaling Fiber Amplifiers Using Very-Large-Mode-Area Fibers

    Science.gov (United States)

    2016-02-23

    implied, of the Air Force Research Laboratory or the U. S. Government. OPS-16-11957; 19 July 2016. Government Purpose Rights. 14. ABSTRACT DEW -class...level, their use in directed-energy weapon ( DEW ) systems require narrow linewidth, which to date has restricted their output power to below 1kW...fiber. Provided the thermal changes are sufficiently slow compared to the mode formation length, any given mode of the fiber will adiabatically