Patent ID: 7456683

Claim:
An amplitude error compensating device comprising: an amplitude correcting section for performing amplitude correction with respect to an in-phase component and a quadrature component of a complex signal obtained by quadrature demodulation, based on amplitude error information, and outputting a resultant amplitude-corrected complex signal; and an amplitude error detecting section for obtaining the amplitude error information, depending on amplitudes of an in-phase component and a quadrature component of the amplitude-corrected complex signal, wherein the amplitude error detecting section comprises: a power difference calculating section for obtaining as a power error a difference in power between the in-phase component and the quadrature component of the amplitude-corrected complex signal; a rotation detecting section for detecting a rotation of a signal point of the amplitude-corrected complex signal, and outputting the result as a rotation detect signal; an error information control section for outputting the power error when the rotation detect signal indicates that a rotation of the signal point has been detected, and 0 when the rotation detect signal indicates that a rotation of the signal point has not been detected; and a smoothing section for smoothing an output of the error information control section, and outputting the result as the amplitude error information.