Microwave double balanced mixer

摘要

A first 3 dB quadrature coupler is connected to an RF input terminal and its outputs are connected to first and second antiphase power dividers. The outputs of the first and second antiphase power dividers are individually connected to the first gate of four dual-gate field effect transistors (FET's). A second 3 dB quadrature coupler is connected to an LO input terminal and its outputs are connected to third and fourth antiphase power dividers. The outputs of the third and fourth antiphase power dividers are individually connected to the second gates of the four FET's. The drains of two of the FET's are connected together and to a low pass filter, and the drains of the other two FET's are connected together and to a second low pass filter. The outputs of the filters are connected to the two inputs of a differential amplifier, and the IF signal is taken at the output of the differential amplifier.