Patent ID: 8792593

Claim:
A radio receiver comprising: an antenna configured to receive a radio signal; a low-noise amplifier configured to amplify an output signal of the antenna with a low noise; a quadrature demodulator configured to demodulate an output signal of the low-noise amplifier, and to generate an analog I signal of an in-phase component and an analog Q signal of a quadrature component; a first analog-to-digital converter (ADC) configured to convert the analog I signal into a digital I signal of the in-phase component; a second analog-to-digital converter (ADC) configured to convert the analog Q signal into a digital Q signal of the quadrature component; a first power calculator configured to calculate a first power expected value of the digital I signal; a second power calculator configured to calculate a second power expected value of the digital Q signal; a correlation value calculator configured to calculate a correlation value between the digital I signal and the digital Q signal; a correction parameter generator configured to generate a correction parameter based on the first power expected value, the second power expected value, and the correlation value between the digital I signal and the digital Q signal; a corrector configured to perform a linear transform operation using the correction parameter, to correct an IQ imbalance of the digital I signal and the digital Q signal, and to generate a corrected I signal and a corrected Q signal; a demodulator configured to demodulate the corrected I signal and the corrected Q signal, and to generate a demodulated signal; and a controller configured to generate a gain control signal in order to control a gain of the low-noise amplifier in such a manner that a thermal noise mixed by the low-noise amplifier is larger than a quadrature demodulation noise mixed by the quadrature demodulator and an analog-digital conversion noise mixed by the analog-to-digital converters, wherein the low-noise amplifier is operated on the basis of the gain control signal.