Fundamental limits of high-efficiency silicon and compound semiconductor power amplifiers in 100-300 GHz bands

Abstract

This paper reviews the requirements for future digital arrays in terms of power amplifier requirements for output power and efficiency and the device technologies that will realize future energy-efficient communication and sensing electronics for the upper millimeter-wave bands (100-300 GHz). Fundamental device technologies are reviewed to compare the needs for compound semiconductors and silicon processes. Power amplifier circuit design above 100 GHz is reviewed based on load line and matching element losses. We present recently presented class-A and class-B PAs based on a InP HBT process that have demonstrated record efficiency and power around 140 GHz while discussing circuit techniques that can be applied in a variety of integrated circuits.