Microwave Subharmonic Image Rejection Mixer

Microwave subharmonic image rejection mixer enables to obtain single side band conversion with the use of halved local oscillator frequency. Main features consists of single 3 dB microwave quadrature coupler and suitable duplexer filters. Antiparallel GaAs schottky diodes have been employed. Frequency conversion exhibits, in this case, advantages of both traditional image rejection and single ended subharmonic mixers [1,2,3]. Mixers have been manufactured in microstrip configuration in the signal frequency ranges of 7, 15, 18, 24 GHz and excellent performance has been reached in 10% instantaneous bandwidth. Theoretical approach and experimental results are presented.