Cryogenic 90 GHz Receiver For Airborne Radiometry

A cryogenic 90 GHz receiver has been developed that has a noise figure of 2.36 dB (DSB) with an instantaneous bandwidth of 1.2 GHz. The cooled front-end consists of a Schottky-barrier mixer with built-in GaAs FET IF amplifier. The system is small in size and has a relatively low weight, so that it can be used for airborne radiometry even in small aircrafts.