To perform desired frequency conversion when the frequency of a local oscillation signal changes over a wide range.

A transmitter-receiver circuit includes: a synthesizer to output a local oscillation signal; first multiphase signal generation means having a plurality of delay circuits connected in multiple stages, which generates from the local oscillation signal fed into the delay circuits a multiphase local oscillation signal; a transmit circuit containing a first mixer circuit which accepts the multiphase signal as its input and converts a transmit signal in baseband bandwidth to a carrier frequency; second multiphase signal generation means which generates from the local oscillation signal fed thereinto a multiphase local oscillation signal; and a receive circuit containing a second mixer circuit which converts the frequency of a received signal at the carrier frequency to a baseband bandwidth. The delay circuits, which are used for generating a first delay time and a second delay time, generates the first delay time or the second delay time whichever is selected.