Patent ID: 7783266

Claim:
A bidirectional frequency converter comprising: a bipolar transistor; a load impedance element connected to a collector terminal of the bipolar transistor; a bias part for supplying a bias to a base terminal of the bipolar transistor; a first switch for permitting and blocking power supply to the bias part; and an emitter impedance element connected to an emitter terminal of the bipolar transistor, wherein an output signal of a second frequency, which is a mixture signal including an input signal of a first frequency input from a first signal terminal connected to the base terminal and a local oscillation signal input from a third signal terminal connected to the emitter terminal, is output from a second signal terminal connected to the collector terminal when the first switch is turned on and a bias is supplied, and wherein an output signal of the first frequency, which is a mixture signal including an input signal of the second frequency input from the second signal terminal and the local oscillation signal input from the third signal terminal, is output from the first signal terminal when the first switch is turned off.