Systematic Design of Hybrid High Power Microwave Amplifiers Using Large Gate Periphery GaN HEMTs

Abstract In this paper, a design methodology for realization of hybrid microwave power amplifiers (PAs) using discrete GaN HEMTs is systematically explained. High power solid-state amplifiers usually suffer from self-heating, high frequency instability, unbalanced feeding effects and suchlike that should be carefully taken into account in a reliable and robust design. Though most of these issues are discussed in some of the previously published literatures, a single self-contained document that systematically describes the hybrid microwave PA design is limited. In this work, a comprehensive design methodology for implementation of high frequency PA is presented while the important challenges of high power amplifier design are discussed in more detail and several useful practical hints are given. Especially, we focus on hybrid PAs that are realized using large gate periphery GaN HEMTs. As a real example, a PA is fabricated using a 0.25  μ m GaN on SiC HEMT transistor with a gate width of 12.5 mm. The fabricated PA achieves a 12 dB small-signal gain, 30 W output power, and 52% PAE across the frequency range of 9–9.8 GHz. The thermal analyses of the power transistor are performed using a 3D model, which is developed in ANSYS software and calibrated by measured data. The model can be used to calculate the transistor channel temperature and consequently predict the device lifetime.

[1]  J. Lees,et al.  A Methodology for Realizing High Efficiency Class-J in a Linear and Broadband PA , 2009, IEEE Transactions on Microwave Theory and Techniques.

[3]  Hartmut Hillmer,et al.  An enhanced quasi-monolithic integration technology for microwave and millimeter wave applications , 2003 .

[4]  Bumman Kim,et al.  Investigation of a Class-J Power Amplifier With a Nonlinear $C_{\rm out}$ for Optimized Operation , 2010, IEEE Transactions on Microwave Theory and Techniques.

[5]  Frederick H. Raab,et al.  Solid State Radio Engineering , 1980 .

[6]  Mohsen Hayati,et al.  Design of a highly PAE class-F power amplifier using front coupled tapered compact microstrip resonant cell , 2013 .

[7]  Hartmut Hillmer,et al.  Quasi-monolithic integration of high-power GaN-based HEMTs for high-frequency applications , 2007 .

[8]  Pui-In Mak,et al.  A 2-$\mu{\hbox{m}}$ InGaP/GaAs Class-J Power Amplifier for Multi-Band LTE Achieving 35.8-dB Gain, 40.5% to 55.8% PAE and 28-dBm Linear Output Power , 2016, IEEE Transactions on Microwave Theory and Techniques.

[9]  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.

[10]  G. Gonzalez.  Microwave Transistor Amplifiers: Analysis and Design , 1984 .

[11]  Nasser Masoumi,et al.  A fully integrated 2.4 GHz CMOS high power amplifier using parallel class A&B power amplifier and power-combining transformer for WiMAX application , 2013 .

[13]  M. Joodaki,et al.  Design and fabrication of hybrid 30-watt X-band GaN-based amplifier , 2016, 2016 16th Mediterranean Microwave Symposium (MMS).

[14]  Paolo Colantonio,et al.  1 KW compact L-band pulsed power amplifier for Radar applications , 2011, 2011 MICROWAVES, RADAR AND REMOTE SENSING SYMPOSIUM.

[15]  Christian Fager,et al.  Highly efficient GaN-HEMT power amplifiers at 3.5 GHz and 5.5 GHz , 2011, WAMICON 2011 Conference Proceedings.

[16]  Kyung-Whan Yeom,et al.  A Design of X-Band 40 W Pulse-Driven GaN HEMT Power Amplifier , 2013 .

[17]  Mohsen Hayati,et al.  A harmonic-suppressed high-efficiency class-F power amplifier with Elliptic-Function low-pass filter , 2016 .

[18]  J. Papapolymerou,et al.  An X-band GaN HEMT hybrid power amplifier with low-loss Wilkinson division on AlN substrate , 2013, 2013 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems (COMCAS 2013).

[19]  K. Kanto,et al.  An X-band 250W solid-state power amplifier using GaN power HEMTs , 2008, 2008 IEEE Radio and Wireless Symposium.

[20]  M. Nakayama,et al.  X- and Ku-band internally matched GaN amplifiers with more than 100W output power , 2012, 2012 7th European Microwave Integrated Circuit Conference.

[21]  Bumjin Kim,et al.  Broadband high efficiency GaN discrete and MMIC power amplifiers over 30 – 2700 MHz range , 2014, 2014 IEEE MTT-S International Microwave Symposium (IMS2014).

[22]  M. L. Edwards,et al.  A new criterion for linear 2-port stability using a single geometrically derived parameter , 1992 .

[23]  Mehdi Forouzanfar,et al.  High efficiency 8.8–9.6 GHz class J power amplifier , 2016, 2016 16th Mediterranean Microwave Symposium (MMS).

[24]  Javad Javidan,et al.  Implementation of a fully integrated 30-dBm RF CMOS linear power amplifier with power combiner , 2011 .

[25]  K. Yamanaka,et al.  An X-band internally-matched GaN HEMT amplifier with compact quasi-lumped-element harmonic-terminating network , 2012, 2012 IEEE/MTT-S International Microwave Symposium Digest.

[26]  Mehdi Forouzanfar,et al.  Efficiency enhancement by employing the transistor nonlinear capacitors effects in a 6W hybrid X‐band Class‐J power amplifier , 2018 .

[27]  Inder Bahl,et al.  Fundamentals of RF and Microwave Transistor Amplifiers , 2009 .

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