35 GHz pulsed HBT MMIC amplifiers

A three-stage MMIC preamplifier and a two-stage power amplifier using GaAs-AlGaAs heterojunction bipolar transistors (HBTs) have been developed for pulsed-power applications at 35 GHz. Both amplifiers have been fully characterized at 35 GHz with RF input power and base bias pulse wave forms having 33% duty cycles and 300 ns pulse lengths. The preamplifier delivers a peak output power of 19.6 dBm at 11% PAE and 12.6 dB associated gain at a bias of VCE=6 V and IC=128 mA. The power amplifier delivers a peak output power of 29 dBm at 15% PAE and 5 dB associated gain after minimal external tuning at a bias of VCE=6 V and IC=600 mA. The monolithic amplifiers reported here are based upon 35 GHz power HBTs and represent the first such amplifiers yet reported.<>