A 16 W, 8 dB Output Back-Off Doherty Power Amplifier in GaN on Si MMIC Technology for FR3

Paper in proceeding, 2026

This paper presents a fully monolithically integrated compact asymmetrical Doherty power amplifier (DPA). The output combiner absorbs the intrinsic output capacitance Cout, of the devices with parallel inductors to resonate with Cout. Furthermore, output back-off (OBO) performance is improved by more than 8 dB thanks to asymmetric architecture, making the DPA suitable for handling high peak-to-average power ratio (PAPR) signals in 6G applications. The DPA implemented in novel Infineon 250 nm RF GaN on Si HEMT technology and was characterized under pulsed-RF measurement conditions, and demonstrates a maximum small signal gain of 9 dB at 7.2 GHz, an output power of 40 – 41.8 dBm at saturation, a saturation power added efficiency (PAE) of 20.9 - 32.7 % and a 8 dB back-off PAE of 15.5 - 26 % across a BW from 7 to 8 GHz, which is equal to 13.3 % fractional bandwidth (FBW), with a compact size of 4 mm × 4 mm, power density 1 W/mm²