Patent ID: 7706494

Claim:
A wireless communication apparatus comprising: a local oscillator which generates a local clock; a transmitter which sends transmitted data wirelessly while mixing it with the local clock; a first frequency divider which generates a first divided clock resulting from the local clock being divided; a spreading waveform generator which generates a spread clock resulting from the first divided clock being spread in the PN pattern; a wired sender which, by sending the spread clock by wire, causes both the transmitter and the receiver to share it; a voltage controlled oscillator which generates a multiplied clock based on a control voltage; a receiver which receives the transmitted data sent from the transmitter while mixing it with the multiplied clock; a second frequency divider which generates a second divided clock resulting from the multiplied clock being divided; a phase comparator which detects a phase difference between the spread clock sent by the wired sender and the second divided clock; and a charge pump circuit which transmits a control voltage corresponding to the phase difference detected by the phase comparator, wherein the spreading waveform generator includes; an edge detector which detects an edge of the PN pattern; an exclusive OR circuit which carries out an exclusive OR operation of the first divided clock and the spread clock; and a switch which, based on a result of the detection of the edge of the PN pattern, switches between a doubled clock resulting from the first divided clock being doubled and an output from the exclusive OR circuit.