A W-band monolithic InGaAs/GaAs HEMT Schottky diode image reject mixer

A W-band monolithic image reject mixer (IRM) utilizing pseudomorphic InGaAs/GaAs high-electron-mobility transistor (HEMT) diodes has been developed. The monolithic circuit integrates two single-balanced HEMT Schottky diode mixers, a W-band Lange coupler, and a Wilkinson power divider on one chip. The image reject mixer including an external hybrid IF 90 degrees coupler has a measured conversion loss of less than 11 dB and a 12-16-dB rejection with 10-dBm local oscillator (LO) drive at 94.15 GHz. The success of this monolithic IRM development is attributed to the excellent device performance, the simple circuit topology, and a rigorous design/analysis methodology.<>