Complementary metal–oxide–semiconductor 60 GHz power amplifier by in-phase power combining and digitally assisted power back-off efficiency enhancement

A two-dimensional in-phase power combining with digitally assisted self-tuning is demonstrated in this study for complementary metal-oxide-semiconductor (CMOS) 60 GHz power amplifier (PA) to improve power efficiency. One digitally assisted 4-way power-combined PA prototype was implemented in 65-nm CMOS process. The performance of measured results show output power of 17.2 dBm, power added efficiency of 11.3% with 1.2 V supply voltage, and up to 170-190% efficiency improvement during power back-off for the entire 7 GHz band at 60 GHz.