Efficiency enhancement of GaN power HEMTs by controlling gate-source voltage waveform shape

Abstract

This paper presents a technique to improve the power added efficiency (PAE) of GaN power amplifiers by an appropriate shaping of the gate source voltage waveform. The proposed technique is based on second harmonic injection at the transistor input. It is applied here to a 15W GaN HEMT die from Cree that has been characterized using an harmonic load pull test bench at L-band.