Compact and high efficiency Doherty power amplifier using a new modulation load range

We propose a new modulating load range for a Doherty power amplifier (DPA) that will maintain maximum drain voltage swing and consequently peak efficiency in over 6-dB power back-off (PBO). At 6-dB PBO, the real part of the new modulating load seen by the main amplifier is less than 2∗Ropt. The new load range allows for the design of a compact, low loss output matching and combiner circuit and a simple single drain bias line for the main and auxiliary amplifiers. The proposed 2-stage DPA using the new modulating loads is designed at 15 GHZ in a 0.15 μm enhancement mode (E-mode) Gallium Arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) process. The proposed DPA achieves a measured Psat of 27 dBm, a peak power added efficiency (PAE) of 41% and a PAE of 34% at 6 dB PBO with a gain of 17 dB.

[1]  Bumman Kim,et al.  The Doherty Power Amplifier: Review of Recent Solutions and Trends , 2015, IEEE Transactions on Microwave Theory and Techniques.

[2]  W.H. Doherty,et al.  A New High Efficiency Power Amplifier for Modulated Waves , 1936, Proceedings of the Institute of Radio Engineers.

[3]  Steve C. Cripps,et al.  RF Power Amplifiers for Wireless Communications, Second Edition (Artech House Microwave Library (Hardcover)) , 2006 .

[4]  Jangheon Kim,et al.  The Doherty power amplifier , 2006, IEEE Microwave Magazine.

[5]  C. F. Campbell,et al.  A K-Band 5W Doherty Amplifier MMIC Utilizing 0.15µm GaN on SiC HEMT Technology , 2012, 2012 IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS).

[6]  Tao Jiang,et al.  POLITECNICO DI TORINO Repository ISTITUZIONALE K-Band GaAs MMIC Doherty Power Amplifier for Microwave Radio With Optimized Driver / , 2022 .

[7]  C.F. Campbell.  A fully integrated Ku-band Doherty amplifier MMIC , 1999, IEEE Microwave and Guided Wave Letters.

[8]  Zoya Popovic,et al.  A 4.2-W 10-GHz GaN MMIC Doherty Power Amplifier , 2015, 2015 IEEE Compound Semiconductor Integrated Circuit Symposium (CSICS).

[9]  F. Giannini,et al.  Increasing Doherty Amplifier Average Efficiency Exploiting Device Knee Voltage Behavior , 2011, IEEE Transactions on Microwave Theory and Techniques.