Amplificador clase J en UHF a GaN HEMT con PAE superior a 80%

Abstract

In this paper, the design of a highly efficient power amplifier (PA) for UHF applications, based on GaN HEMT technology, is presented. After reviewing the principles of class J operation, a lumped element implementation of the multiharmonic output matching network is proposed, aimed to synthesize the desired slightly inductive and reactive termination loads at the fundamental and second harmonic respectively. The PA provides a peak power added efficiency (PAE) over 80%, with a gain profile typical of class AB solutions, and amenable for digital predistortion. The PAE value also keeps over 70% within a 200 MHz bandwidth, while the power capability may reach 30 W for high drain biasing values.