A 1-Watt 38 GHz Power Amplifier Using 0.1-μm GaAs p-HEMT Technology

The paper presents a 38 GHz power amplifier using 0.1-$\mu {\mathrm {m}}$ D-mode GaAs pseudomorphic high electron mobility transistor (p-HEMT) technology for the fifth generation (5G) mobile communications. Utilizing four-way direct shunt power combining and low impedance transmission line pre-matching techniques, the measured saturation output power of the PA is 30.2 dBm and the output 1-dB gain compression point $({OP}_{1dB})$ is 29.4 dBm at 38 GHz. The measured peak power added efficiency (PAE) is 23.4 % and the PAE at OP1dB is 20.8 %. The small signal gain is 18.4 dB at 38 GHz and the chip size is $2.9 \times 1.8\ {\mathrm {mm}}^{2}$.