Patent ID: 8218659

Claim:
A demodulation device for demodulating an Orthogonal Frequency Division Multiplexing (OFDM) signal received through a transmission path, the demodulation device comprising: a correlator for detecting a correlation signal based on the OFDM signal; a delay indicator calculator for calculating at least two of a plurality of delay indicator values including a first delay indicator value indicating a delay time interval determined based on a correlation value having a predetermined difference from a maximum peak value of the correlation signal in a symbol duration of the OFDM signal, a second delay indicator value indicating a change of a delay time interval determined based on a time during which a value of the correlation signal is equal to or greater than a predetermined correlation value in the symbol duration of the OFDM signal, and a third delay indicator value indicating a change of a time difference between a main path peak and a delay path peak in the symbol duration of the OFDM signal; a delay indicator determinator for calculating respective probabilities of the at least two delay indicator values exceeding respective reference values in a plurality of symbol durations of the OFDM symbol; and a transmission path state estimator for generating a state estimation value of the transmission path based on the respective probabilities of the at least two delay indicator values.