High efficiency quadrature HBT power amplifier optimized for use with digital predistortion

摘要

We demonstrate a 28dBm high efficiency quadrature power amplifier for use with LTE signals and digital predistortion (DPD). The PA is fabricated in an InGaP heterojunction bipolar transistor (HBT) process. It achieves an efficiency of 28% at an average output power of 28dBm with a 5V power supply. To the best of the authors knowledge this is the highest efficiency reported for a non-Doherty multi-stage power amplifier when operated at 8dB power back-off from Psat.