A Study of Interpulse Instability in Gallium Nitride Power Amplifiers in Multifunction Radars

The incorporation of gallium nitride (GaN) power amplifiers (PAs) into future high-power aperture radar systems is certain; however, the introduction of this technology into multifunction radar systems will present new challenges to radar engineers. This paper describes a broad investigation into amplitude and phase transients produced by GaN PAs when they are excited with multifunction radar waveforms. These transients are the result of self-heating electrothermal memory effects and are manifested as interpulse instabilities that can negatively impact the coherent processing of multiple pulses. A behavioral model based on a Foster network topology has been developed to replicate the measured amplitude and phase transients accurately. This model has been used to develop a digital predistortion technique that successfully mitigates the impact of the transients. The moving target indicator improvement factor and the root mean square pulse-to-pulse stability are used as a metric to assess the impact of transients on radar system performance and to test the effectiveness of a novel digital predistortion concept.

[1]  L. Marescialli,et al.  Pulse-to-Pulse Stability Characteristics of Robust Design Centered High Performances/Low Cost T/R Module , 2006, 2006 European Microwave Conference.

[2]  W. Pribble,et al.  Thermal analysis and its application to high power GaN HEMT amplifiers , 2009, 2009 IEEE MTT-S International Microwave Symposium Digest.

[3]  Allen Katz,et al.  Evaluation and correction of time dependent amplifier non-linearity , 1996, 1996 IEEE MTT-S International Microwave Symposium Digest.

[4]  L. Marescialli,et al.  Pulse-to-Pulse Stability Characteristics of Robust Design Centered High Performances/Low Cost T/R Module , 2006, 2006 European Radar Conference.

[5]  Katja Gruenewald,et al.  Managing Temperature Effects In Nanoscale Adaptive Systems , 2016 .

[6]  J.C.M. Hwang,et al.  A phenomenologically based transient SPICE model for digitally modulated RF performance characteristics of GaAs MESFETs , 2001 .

[7]  F.M. Ghannouchi,et al.  Dynamic electro-thermal behavioral model for RF power amplifiers , 2003, IEEE MTT-S International Microwave Symposium Digest, 2003.

[8]  J. Hoffman,et al.  Radar waveform pulse analysis measurement system for high-power GaN amplifiers , 2012, 79th ARFTG Microwave Measurement Conference.

[9]  Yu-chao Wang.  Electrical and Thermal Analysis of Gallium Nitride HEMTs , 2009 .

[10]  R. S. Pengelly,et al.  A Review of GaN on SiC High Electron-Mobility Power Transistors and MMICs , 2012, IEEE Transactions on Microwave Theory and Techniques.

[11]  David J. Allstot,et al.  Modeling of frequency and temperature effects in GaAs MESFETs , 1990 .

[12]  Stephane Cote.  Naval Multi-Function RADAR , 2010, 2010 IEEE Radar Conference.

[13]  B. Bunz,et al.  Accurate Large-Signal Modeling of AlGaN-GaN HEMT Including Trapping and Self-Heating Induced Dispersion , 2006, 2006 IEEE International Symposium on Power Semiconductor Devices and IC's.

[14]  K. Webb,et al.  A temperature-dependent nonlinear analytic model for AlGaN-GaN HEMTs on SiC , 2004, IEEE Transactions on Microwave Theory and Techniques.

[15]  H. A. Hung,et al.  Dependence of GaN HEMT Millimeter-Wave Performance on Temperature , 2009, IEEE Transactions on Microwave Theory and Techniques.

[16]  Alexander A. Balandin,et al.  Electrothermal simulation of the self-heating effects in GaN-based field-effect transistors , 2006 .

[17]  L Cabria,et al.  Temperature dependent memory effects on a drain modulated GaN HEMT power amplifier , 2010, 2010 Workshop on Integrated Nonlinear Microwave and Millimeter-Wave Circuits.

[18]  T. J. Brazil,et al.  Nonlinear Electrothermal GaN HEMT Model Applied to High-Efficiency Power Amplifier Design , 2013, IEEE Transactions on Microwave Theory and Techniques.

[19]  Slim Boumaiza,et al.  Behavioral modeling and digital predistortion of Power Amplifiers with memory using Two Hidden Layers Artificial Neural Networks , 2010, 2010 IEEE MTT-S International Microwave Symposium.

[20]  David C. Look,et al.  Traps in AlGaN/GaN/SiC heterostructures studied by deep level transient spectroscopy , 2005 .

[22]  Karel J. Keesman,et al.  System Identification: An Introduction , 2011 .

[23]  Jasprit Singh,et al.  Transient study of self-heating effects in AlGaN/GaN HFETs: Consequence of carrier velocities, temperature, and device performance , 2007 .

[24]  Long Nguyen,et al.  Memory effect reduction for LDMOS bias circuits , 2003 .

[25]  M. Beach,et al.  The application of GaN HEMTs to pulsed PAs and radar transmitters , 2012, 2012 7th European Microwave Integrated Circuit Conference.

[26]  Timo Rahkonen,et al.  Measurement technique for characterizing memory effects in RF power amplifiers , 2001 .

[27]  Slim Boumaiza,et al.  Systematic estimation of memory effects parameters in power amplifiers' behavioral models , 2011, 2011 IEEE MTT-S International Microwave Symposium.

[28]  J.A. del Alamo,et al.  A Simple Current Collapse Measurement Technique for GaN High-Electron Mobility Transistors , 2008, IEEE Electron Device Letters.

[29]  R. Sommet,et al.  Electro-thermal behavioral modeling of RF power amplifier taking into account load-pull effects for narrow band radar applications , 2011, 2011 6th European Microwave Integrated Circuit Conference.

[30]  K.C. Lauritzen,et al.  High-Dynamic-Range Receivers for Digital Beam Forming Radar Systems , 2007, 2007 IEEE Radar Conference.

[31]  J.C. Pedro,et al.  A comparative overview of microwave and wireless power-amplifier behavioral modeling approaches , 2005, IEEE Transactions on Microwave Theory and Techniques.

[32]  S. Leonov.  MTI radar stability measurement error , 2001, 2001 CIE International Conference on Radar Proceedings (Cat No.01TH8559).

[33]  J.M. Nebus,et al.  A system level model of solid state amplifiers with memory based on a nonlinear feedback loop principle , 2005, 2005 European Microwave Conference.

[34]  T. Kazior,et al.  Trapping effects in GaN and SiC microwave FETs , 2002, Proc. IEEE.

[35]  C.P. Silva,et al.  Validation of power amplifier nonlinear block models , 1999, 1999 IEEE MTT-S International Microwave Symposium Digest (Cat. No.99CH36282).

[36]  T. Chao,et al.  Temperature Dependence of Electron Mobility on Strained nMOSFETs Fabricated by Strain-Gate Engineering , 2012, IEEE Electron Device Letters.

[37]  Yutaka Ohno,et al.  A study on current collapse in AlGaN/GaN HEMTs induced by bias stress , 2003 .

[38]  Clement Tolant,et al.  Measured and Simulated Impact of Irregular Radar Pulse Trains on the Pulse-to-Pulse Stability of Microwave Power Amplifiers , 2014, IEEE Transactions on Microwave Theory and Techniques.

[39]  H. A. Hung,et al.  Temperature Dependence of GaN HEMT Small Signal Parameters , 2011 .

[40]  C. Salmer,et al.  Pulse to Pulse Stability of Solid State Transmitter Module for Radars Application , 1998, 1998 28th European Microwave Conference.

[41]  Qing Li,et al.  Performance analysis of a novel real-time closed-loop technique for non-linearity correction of power amplifiers , 2007, 2007 IEEE Sarnoff Symposium.

[42]  Christian Fager,et al.  Modeling of long term memory effects in RF power amplifiers with dynamic parameters , 2012, 2012 IEEE/MTT-S International Microwave Symposium Digest.

[43]  Christian Fager,et al.  A Comparative Analysis of the Complexity/Accuracy Tradeoff in Power Amplifier Behavioral Models , 2010, IEEE Transactions on Microwave Theory and Techniques.

[44]  A. Bachmann,et al.  Variable Precision Two-Channel Phase, Amplitude, and Timing Measurements for Radar Interferometry and Polarimetry , 2007, IEEE Transactions on Microwave Theory and Techniques.

[45]  D. Grider,et al.  Drain current compression in GaN MODFETs under large-signal modulation at microwave frequencies , 1999 .

[46]  C. Campbell,et al.  GaN Takes the Lead , 2012, IEEE Microwave Magazine.

[47]  Fadhel M. Ghannouchi,et al.  Thermal memory effects modeling and compensation in RF power amplifiers and predistortion linearizers , 2003 .

[48]  John Wood,et al.  Modeling and Characterization of RF and Microwave Power FETs , 2007 .

[49]  Temperature dependence of electron concentration and mobility in n-GaN measured up to 1020 K , 2010 .

[50]  R. Quere,et al.  Behavioral Thermal Modeling for Microwave Power Amplifier Design , 2007, IEEE Transactions on Microwave Theory and Techniques.

[51]  A. Zhu,et al.  Dynamic Deviation Reduction-Based Volterra Behavioral Modeling of RF Power Amplifiers , 2006, IEEE Transactions on Microwave Theory and Techniques.

[52]  A. Ghorbani,et al.  Polynomial Based Predistortion for Solid State Power Amplifier Nonlinearity Compensation , 2006, 2006 IEEE North-East Workshop on Circuits and Systems.

[53]  C. G. Tua.  Measurement technique to assess the impact of RF power amplifier memory effects on radar performance , 2012, 2012 IEEE Radar Conference.

[54]  J.M. Nebus,et al.  A new behavioral model taking into account nonlinear memory effects and transient behaviors in wideband SSPAs , 2002, 2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278).

[55]  J. Laskar,et al.  RF performance and thermal analysis of AlGaN/GaN power HEMTs in presence of self-heating effects , 2002, 2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278).

[56]  Timo Rahkonen,et al.  Cancelling the memory effects in RF power amplifiers , 2001, ISCAS 2001. The 2001 IEEE International Symposium on Circuits and Systems (Cat. No.01CH37196).

[57]  J. M. Tirado,et al.  Trapping Effects in the Transient Response of AlGaN/GaN HEMT Devices , 2007, IEEE Transactions on Electron Devices.

[58]  E. D. Cohen.  The MIMIC Program—A Retrospective , 2012, IEEE Microwave Magazine.

[59]  F. Filicori,et al.  Characterization of the Nonlinear Thermal Resistance and Pulsed Thermal Dynamic Behavior of AlGaN–GaN HEMTs on SiC , 2013, IEEE Transactions on Microwave Theory and Techniques.

[60]  W. Bosch,et al.  Measurement and simulation of memory effects in predistortion linearizers , 1989 .

[61]  Zhifu Hu,et al.  Electro-thermal model extraction of power GaN HEMT using I–V pulsed and DC measurements , 2011, 2011 9th IEEE International Conference on ASIC.

[62]  D. Wisell,et al.  Derivation of a behavioral RF power amplifier model with low normalized mean-square error , 2007, 2007 European Microwave Conference.

[63]  Edouard Ngoya,et al.  Handling long-term memory effects in X-parameter model , 2012, 2012 IEEE/MTT-S International Microwave Symposium Digest.

[64]  Magnus Isaksson,et al.  A study of a variable-capacitance drain network's influence on dynamic behavioral modeling of an RF power amplifier , 2007, 2007 69th ARFTG Conference.