Patent ID: 7433419

Claim:
An ICI (Inter-Channel Interference) cancellation method for use in an OFDM (Orthogonal Frequency Division Multiplexing) communication system in which a receiver performs channel estimation using pilot subcarriers included in transmission signals transmitted from at least one transmitter, the method comprising: generating a transmission signal in which pilot subcarriers and data subcarriers are regularly arranged; precoding the transmission signal; modulating the pre-coded transmission signal into an OFDM symbol; transmitting the OFDM symbol; receiving the OFDM symbol; demodulating the OFDM symbol; detecting the pilot subcarriers from the demodulated signal; estimating channels using the pilot subcarriers; and restoring the transmission signal using the estimated channels, wherein the step of precoding the transmission signal comprises: generating a precoding matrix according to an arrangement of the pilot subcarriers; and multiplying the transmission signal by the precoding matrix and the precoding matrix includes first matrices being multiplied with the pilot subcarriers, second matrices being multiplied with the data subcarriers, and non-diagonal entries of 0's.