Optical control of microwave signals using GaAs FETs

The distinct advantages of optical transmission systems and the increasing use of microwave frequencies within general communication systems, coupled with the ability to integrate microwave and optical components onto a single slice of gallium arsenide have stimulated considerable interest in the development of microwave optoelectronic systems. The paper reviews the electro-optic techniques for achieving direct optical control of microwave signals, and provides some insight into the historical development of the subject. The physical mechanisms involved in the interaction of optical and microwave signals are described through the consideration of photo-effects within microwave GaAs FETs. Current applications relevant to hybrid and monolithic constructions are given and the discussion extended to potential future developments