Aspects of Millimeter-Wave Power Generation at EHF Frequencies

Renewed interest in the EHF frequency band for military communications has led to the demand for efficient, wideband high-power solid-state amplifiers and associated millimeter-wave components. This paper reviews the state-of-the-art of IMPATT diode power amplification at Q-band and discusses the design techniques which are used in the development of unconditionally stable IMPATT amplifiers as well as injection-locked designs. Various techniques for increasing output power are identified and the performance limitations associated with each technique are mentioned. Important concerns associated with the military application of these amplifiers are presented, including questions of reliability and circuit redundancy.