Patent ID: 7903771

Claim:
A time-domain IQ mismatch detection apparatus for detecting mismatch between an I-channel signal and a Q-channel signal in unit of a sample included in a symbol of an OFDM (orthogonal frequency division multiplexing) signal received by an OFDM receiver, the time-domain IQ mismatch detection apparatus comprising a phase IQ mismatch detection unit, wherein the phase IQ mismatch detection unit comprises: a first delayer which delays an input I-channel signal by one sample interval; a second delayer which delays an input Q-channel signal by one sample interval; a first phase mismatch detector which multiplies a currently-input I-channel signal with a currently-input Q-channel signal and output a result thereof; a second phase mismatch detector which multiplies the currently-input I-channel signal and the delayed Q-channel signal and output a result thereof; a third phase mismatch detector which multiplies the delayed I-channel signal with the currently-input Q-channel signal and output a result thereof; and a phase error arithmetic unit which multiplies the outputs of the second and third phase mismatch detectors with an attenuation coefficient, adds results thereof, and subtracts the addition result from the output of the first phase mismatch detector to output a phase error value.