A Highly Linear 25–32 GHz Power Amplifier with 22-dBm Output Power and 30% PAE in 130-nm SiGe BiCMOS

In this paper, a two-stage, two-way transformer combined power amplifier (PA) operated in 25–32 GHz frequency range in 130-nm SiGe BiCMOS technology is proposed. We propose the output cell parameters optimization targeting high gain, OP
1dB
, and PAE for SiGe BiCMOS HBT. Based on the derived transformer model and graphical matching procedure, we present an optimization methodology to design low loss output, inter-stage and input transformers. The inductive source degeneration is utilized to broaden impedance matching bandwidth. Measurement results show that the proposed PA achieves 26 dB gain, 1-dB compressed output power of 22.1-dBm and 30% power-added efficiency (PAE) at 1-dB compression point.