Patent ID: 7817968

Claim:
A transmitter and receiver circuit comprising: a plurality of antennas for receiving high-frequency signals, a local oscillator for generating a local oscillation signal, a plurality of mixers, each mixer being directly connected to a corresponding one of the antennas, for converting the frequency of the high-frequency signals received through the corresponding antenna, in response to input of the local oscillation signal, to the respective mixer, and a switch including an input port connected to the local oscillator and a plurality of output ports, each output port being connected to a corresponding mixer, for selectively supplying the local oscillation signal to a selected one of the output ports, whereby, when the output port selected is connected to one of the mixers, a receiving channel is selected by switching of the switch, wherein the switch includes a transmitter circuit output port connected to a transmitting circuit for supplying the oscillator signal to the transmitting circuit, so that transmitting and receiving by the transmitting and receiver circuit are controlled by switching of the switch.