A 50 GHz GaAs FET MIC transmitter/receiver using hermetic miniature probe transitions

A very compact 50-GHz-band transmitter/receiver for a video link is described. The RF assemblies used in the system consist of 25/50-GHz frequency doublers, a 25-GHz dielectric-resonator oscillator, and a 25-GHz FM modulator. The circuits make extensive use of microwave integrated circuit (MIC) technology with all GaAs FETs as active elements. The frequency doublers exhibit a minimum conversion loss of 2.6 dB and a maximum output power of 11 dBm. The modulator is highly frequency stabilized by the dielectric resonator. Recently developed miniature probe microstrip-to-waveguide transitions permit the MIC assemblies to be installed compactly in hermetically sealed packages. Design considerations and experimental data for the transition are presented. Using these technologies a transmitting power of 10 dBm and a receiver noise figure of 13 dB have been obtained. >