Efficiency improvement of Doherty power amplifiers using supply switching and gate bias modulation

摘要

A new low cost efficiency improvement technique is proposed for Doherty power amplifiers (PA), which combines supply switching with typical load modulation. In addition, the technique employs gate bias modulation to provide gain and maximize efficiency. The proposed technique was investigated with a commercial prototype GaN PA. Measurement and simulation results for a 5 MHz LTE signal showed that the proposed technique significantly improved the average power-added efficiency (PAE) of Doherty PA to ~55 %.