A 26-GHz Linear Power Amplifier with 20.8-dBm OP1dB Supporting 256-QAM Wideband 5G NR OFDM for 5G Base Station Equipment

This paper presents a high output power and linearity power amplifier (PA) in 65nm CMOS SOI process for 5G communications. A two-way power combining topology with peaking inductive technique is utilized for high output power. Additionally, the PMOS compensate capacitor, second-order harmonic traps and low impedance network are proposed to improve linearity for wideband modulation. The PA achieves a gain of 19 dB at 26 GHz with 3-dB bandwidth from 22.3 GHz to 28.6 GHz. The PA also realizes 20.8 dBm OP1dB and 21.3 dBm Psat with a peak PAE of 26.15% at 26 GHz. In modulation signal test, using a 5G NR 400 MHz l-CC 64-QAM and 256-QAM OFDM signal, this PA demonstrates 5% and 3% rms error vector magnitude (EVM) with average output power (Pavg) of 15.5 dBm and 14.4 dBm, respectivly.