Design of a wideband harmonically tuned Class-J Power Amplifier

Abstract

This paper describes a modern design idea of wideband and high efficient GaN HEMT Class-J power amplifiers. The operation principle of the Class-J mode, based on the second harmonic tuning, is introduced which can maximize the achievable efficiency. Matching network synthesis criteria for wideband frequency response are addressed for 5G power amplifiers design. This wideband harmonically tuned technique is applicable to amplifiers based on adjusting the shape of the waveforms through a a finite number of harmonics, such as Class-F,F−1 and E. Simulation results indicate that Class-J can provide a high drain efficiency of 70% across a 1.5 to 3.2 GHz bandwidth while delivering 10W output power at the 1dB- compression point, using GaN technology.