Patent ID: 7986615

Claim:
A demodulating circuit comprising: Fast Fourier Transform (FFT) processing means for performing an FFT process on an Orthogonal Frequency Division Multiplexing (OFDM time-domain signal; intercarrier interferential component removing means for removing an intercarrier interferential component from an OFDM frequency-domain signal which is produced when the FFT process is performed on the OFDM time-domain signal by said FFT processing means; extracting means for extracting pilot signals representative of transmission path characteristics of a transmission path from said OFDM frequency-domain signal from which the intercarrier interferential component is removed by said intercarrier interferential component removing means; transmission path characteristics estimating means for estimating transmission path characteristics represented by subsequently received pilot signals, based on the transmission path characteristics represented by said pilot signals extracted by said extracting means; interpolating means for interpolating transmission path characteristics in a frequency direction based on the transmission path characteristics estimated by said transmission path characteristics estimating means thereby to estimate transmission path characteristics for all subcarriers; symbol sequence estimating means for estimating a symbol sequence represented by said OFDM frequency-domain signal which is produced when the FFT process is performed on the OFDM time-domain signal by said FFT processing means, based on the transmission path characteristics for all subcarriers which are estimated by said interpolating means; and interference replica generating means for generating an interference replica representing said intercarrier interferential component to be removed from said OFDM frequency-domain signal by said intercarrier interferential component removing means, based on the symbol sequence estimated by said symbol sequence estimating means and the transmission path characteristics for all subcarriers which are estimated by said interpolating means.