Frequency offset compensation apparatus and frequency offset compensation method

摘要

A frequency offset compensator according to the present invention comprises a first FFT means for performing a discrete time Fourier transform of an input signal, a second FFT means for performing a discrete time Fourier transform, and a second FFT means for performing a discrete Fourier transform on the frequency of the output data of the first FFT means, And an offset compensating means for varying in accordance with the offset compensation amount, further rearranging and inputting to the second FFT means. This enables frequency offset compensation without requiring a new complex multiplier or memory in optical communications.