Design of a multi-octave power amplifier with a novel broadband design methodology

Abstract

This paper presents a multi-octave power amplifier based on a modified simplified real frequency method. The approximate range of the optimal impedance of the transistor in the wide band on the Smith chart is obtained by the load-pull technique, and the coincidence degree of the optimal impedance value and the input impedance value of the matching circuit is taken as a new optimization objective and added into the algorithm. Then the improved algorithm is used to design the amplifier’s wideband matching circuit. In order to verify validity, a 0.5-2.8GHz power amplifier is designed and fabricated. And the measured results show that the saturated output power is between 40.0dBm and 42.8dBm in target band. From 63% to 69% drain efficiency is obtained with a gain from 10dB to 12dB.