28 GHz GaAs pHEMT High-Efficiency Power Amplifier Using Multi-Section Transmission-Line Power Combining/Matching Technique

This paper presents a 28-GHz, 1-W power amplifier (PA) with 41% peak PAE fabricated in a 0.15-μm GaAs pHEMT process. The proposed multi-section low-impedance transmission line matching network can adequately combine the output power and provide a low-loss output matching network in a compact area. The measured small-signal gain is 18.7 dB, and the measured saturated output power (P
SAT
) is 30.1 dBm with a peak power-added efficiency (PAE
MAX
) of 41% at 28 GHz.