A Dual-Band GaN MMIC Power Amplifier With Hybrid Operating Modes for 5G Application

This letter implements a 3.5-/5.8-GHz dual-band power amplifier (PA) with hybrid operating modes for 5G mobile communication and vehicle network using a 0.25-μm gallium nitride (GaN)-HEMT process. For the 3.5-GHz band, the PA operates in the Doherty mode, and the performance is optimized for a high back-off efficiency and a large bandwidth. For the 5.8-GHz band, the PA operates in class-AB mode, and optimal saturation efficiency is used as the design goal. According to the measurement results, a saturated power of 41.8-42.6 dBm, a saturated drain efficiency (DE) of 56%-64%, and a 6-dB back-off DE of 42%-51% are achieved from 3.3 to 3.8 GHz, while the saturated power and DE at 5.8 GHz are 41 dBm and 55%, respectively. To our best knowledge, this is the first dualband GaN monolithic microwave integrated circuit PA designed for hybrid operating modes.