A technique of frequency hopping communication capable of high-speed
switching of a plurality of signals having ultra-wide band 528 MHz
bandwidth at high-speed and setting and switching a band center frequency
and the number of bands arbitrary is provided. A radio transceiver has a
frequency hopping communication function of UWB system for switching the
ultra wide band signal. In the device, high-speed frequency hopping is
realized by controlling an SSB mixer in a local oscillator circuit and
switching the frequency of a DDS. The device sets NCO data to the DDS and
switches a quadrature phase signal of an output, and switches a signal
input of an input terminal of the SSB mixer by a control of a phase
switching switch. One of a sum component and a difference component of a
mixture of first and second quadrature phase signals is outputted from
the output terminal of the SSB mixer.