Patent ID: 8811537

Claim:
A receiving apparatus for a wireless communication system using multiple antennas, the receiving apparatus comprising: an RF unit comprising a predetermined number of receiving ends configured to receive signals received from a predetermined number of transmitting ends through multiple paths; a signal conversion and compensation unit configured to receive signals outputted from the RF unit, convert analog signals into digital signals, remove DC components from the digital signals, and compensate in-phase and quadrature-phase (I/Q) mismatch; a saturation based carrier sensing unit configured to sense a carrier according to saturation state degrees of the digital signals, and provide saturation state information; an automatic gain control unit configured to receive the digital signals and the saturation state information and perform an automatic gain control thereon; a noise matching amplification unit configured to equalize noise levels on the multiple paths by amplifying and attenuating as needed according to a predetermined preset ratio previously stored in a programmable register by using information on the automatic gain control during a predetermined period, the information provided from the automatic gain control unit; and a carrier frequency offset (CFO)/phase correction and fast Fourier transform (FFT) process unit configured to correct a carrier frequency offset of a signal outputted from the noise matching amplification unit, and perform an FFT process to compensate a phase of the signal outputted from the noise matching amplification unit, wherein the predetermined preset ratio is determined by selecting a ratio responsive to the path having the largest signal magnitude among the multiple paths, and wherein the path having the largest signal magnitude is determined by noise calibration.