Patent ID: 7706428

Claim:
An apparatus-implemented method of reducing inter-carrier interference (ICI) for a kth sub-carrier of an orthogonal frequency division multiplexing (OFDM) signal received at time t, wherein the received OFDM signal comprises a plurality of sub-carriers, the method comprising: the apparatus generating a self interference term, ICI k−L,k−L , for a signal received on sub-carrier k−L, wherein L ∈ [ . . . , −3, −2, −1, 1, 2, 3, . . . ], and wherein the self-interference term is an estimate of the data received at time t on the sub-carrier k−L, weighted by a rate of change of the channel through which sub-carrier k−L passes at time t; obtaining an ICI cancellation coefficient, G L ; generating an estimated ICI term by adjusting the self-interference term, ICI k−L,k−L , by an amount based on the ICI cancellation coefficient, G L ; and subtracting the estimated ICI term from a term representing a signal received on the kth sub-carrier at the time t, wherein the ICI cancellation coefficient, G L , is determined as a function of a window function, wherein the term representing the signal received on the kth sub-carrier at time t is obtained by performing: applying the window function to the received OFDM signal to generate a set of selected weighted samples, wherein: a symbol transmitted on the OFDM signal is represented by N samples; the window function has a size that is greater than N; the set of selected weighted samples comprises a central portion of samples, and at least one of an initial portion of samples and a final portion of samples; and the central portion of samples consists of N samples; performing a wrap function on the set of selected weighted samples to generate a set of N combined weighted samples by, if the set of selected weighted samples includes the initial portion of samples, then combining the initial portion of samples with a like number of samples selected from the central portion of samples, and by, if the set of selected weighted samples includes the final portion of samples, then combining the final portion of samples with a like number of samples selected from the central portion of samples; and performing a Fast Fourier Transform on the N combined weighted samples.