A 15.7-21.4 GHz Power Amplifier with 28.2-dBm P _sat and 33.1% PAE _peak in 0.18-μm GaAs pHEMT Process for 6G FR3 Applications

In this paper, a 15.7-21.4 GHz power amplifier (PA) in 0.18-μm gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) process for sixth-generation wireless communication systems (6G) FR3 applications is realized. This PA is designed with three-stage single-ended common-source amplifiers. Due to the physical constraints, III-IV compound transistors are more unstable in contrast to CMOS. Therefore, this paper utilizes LC high-pass filters and small series resistors to improve the stability of the circuit. The measured small signal result shows that the PA achieves 5.7 GHz 3-dB bandwidth and 25.5 dB peak gain. In addition, the measured large signal result shows that the PA delivers 28.2 dBm saturated output power (P<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sat</inf>) and 33.1 % maximum power-added efficiency (PAE<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">peak</inf>). The total chip area consumes 2.8 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>.