A 4.5-GHz-Band Miniature Outphasing GaN HEMT MMIC Power Amplifier

A miniature outphasing power amplifier MMIC has been developed at the 4.5-GHz band for the latest and future wireless communication systems. The outphasing amplifier circuit was successfully integrated into the MMIC by applying a compact outphasing output combiner, based on a dual-powerlevel design technique. The fabricated GaN HEMT outphasing power-amplifier MMIC exhibited a peak drain efficiency of 63% with a maximum output power of 35dBm at 4.6GHz. In addition, a drain efficiency of more than 40% was maintained within an output back-off of 8dB.