Design of a $5 \mathrm{W}, 28-32 \text{GHz}$ Doherty Power Amplifier Using $150-\text{nm}$ GaN Technology for 5G NR FR2 mmWave Communications

This paper presents a 5W MMIC Doherty Power Amplifier (DPA) operating in the Ka-band (28-32 GHz). The simulated and measured S-parameters and power performance are compared to those of a 5 W MMIC Class AB conventional reactively-matched power amplifier having similar chip area. Both amplifiers exhibit a peak linear gain of 20.8 dB. At saturation, the Class AB amplifier demonstrates a peak Power-Added Efficiency (PAE) ranging from 31% to 36% with an output power of 37 dBm, while the DPA achieves a peak PAE of 29% to 33% with a similar output power. As expected at 6 dB output back-off (OBO), the DPA shows a significantly higher PAE of 24% to 31%, compared to the Class AB amplifier's 16% to 22%. The amplifiers demonstrate performances in line with the latest state-of-the-art published results.