Patent ID: 7058002

Claim:
An OFDM packet communication receiver comprising: a receiving means ( 102 ) for receiving OFDM signals and carrying out a predetermined process to said OFDM signals, a synchronization means ( 103 ) for timing synchronization and carrier frequency synchronization for the received OFDM signals provided by said receiving means ( 102 ), a Fourier transform means ( 105 ) for carrying out Fourier transform of said received OFDM signals provided by said synchronization means to divide them into subcarrier signals for each OFDM symbol, a channel estimation means ( 106 ) for estimating channel condition of each subcarrier by using the subcarrier signals divided by said Fourier transform means, a coherent detection means ( 107 ) for carrying out coherent detection of the subcarrier signals divided by said Fourier transform means by using the channel estimation result provided by said channel estimation means, wherein a clock frequency error estimation means ( 100 ) for detecting phase rotation or accumulated phase rotation of a part or all of the coherently detected signals provided by the coherent detection means caused by clock frequency error between a transmitter and a receiver by detecting phase difference between the coherently detected signal (R 1 , R 2 ) and a reference signal (S 1 through S 16 ), and generating phase rotation information (Δθ) of each subcarrier signal caused by said clock frequency error (f RCLK −f TCLK ), a phase rotation compensation means ( 109 ) for compensating the phase rotation of the coherently detected signals provided by said coherent detection means caused by clock frequency error according to said phase rotation information generated by said clock frequency error estimation means, and a decision means ( 112 ) for decision processing for the phase compensated coherently detected signals provided by said phase rotation compensation means.