A Ka-Band Highly Linear Power Amplifier with a Linearization Bias Circuit

A Ka-band highly linear power amplifier (PA) with a linearization bias circuit implemented in 0.25 ┬Ám SiGe BiCMOS for 5G millimeter-wave (mm-wave) phased arrays is presented in this paper. The PA demonstrates a measured 12.5-dB small signal gain, 16.5-dBm saturated output power and 31.1% peak power added efficiency (PAE) at 27 GHz. At 27.5 GHz, the proposed PA is tested with an 800 MHz bandwidth 64-QAM signal without digital predistortion, which achieves a PAE of 18.55%, error vector magnitude (EVM) of -29.6dB, and adjacent channel leakage ratio (ACLR) of -30.05dBc at an average output power of 11.44dBm.