20-GHz 5-dB-gain analog multipliers with AlGaAs/GaAs HBTs

From-DC-to-above-20-GHz monolithic Gilbert cell analog multipliers have been developed using AlGaAs/GaAs HBT technology. As a double balanced active mixer, it exhibits very high conversion gain of above +5 dB with extremely high LO-IF isolation of 33 dB for RF/LO inputs up to 20 GHz. It exhibits conversion gain of +9 dB for 5 GHz RF/LO inputs. As a double balanced upconverter, it exhibits positive conversion gain with high LO-RF isolation of 23 dB for RF output up to 8.5 GHz. As a detection mixer in coherent optical heterodyne receivers, it can operate for RF/LO inputs up to 15 GHz under a less than -7.5 dBm LO input condition