Double balanced mixing

摘要

A double balanced mixer comprising a plurality of transistors, each transistor being adapted to operate in the microwave frequency range and including an input electrode, a control electrode, and an output electrode, the transistors being arranged in a ring configuration with the control electrodes of a first pair of the transistors being interconnected and the control electrodes of a second pair of the transistors being interconnected; circuitry for coupling an input signal having a frequency within a predetermined frequency band in the microwave frequency range to the input electrodes of the ring of transistors and for producing a 180 DEG relative phase difference between the input signal applied to the input electrodes of first transistors of the first and second pairs of transistors and the input signal applied to the input electrodes of second transistors of the first and second pairs of transistors; circuitry for coupling a local oscillator signal to the control electrodes of the ring of transistors and for producing a 180 DEG relative phase difference between the local oscillator signal applied to the control electrodes of the first pair of transistors and the local oscillator signal applied to the control electrodes of the second pair of transistors; and circuitry for biasing the plurality of transistors in their linear operating regions; whereby the ring of transistors produces at the output electrodes an output signal having a frequency which is a function of the frequencies of the input signal and the local oscillator signal for input signals within the predetermined frequency band.