Demodulation method and apparatus

A demodulating apparatus for demodulating orthogonal frequency division multiplexing (OFDM) signals, comprising:

• carrier frequency correction means for complex-multiplying carrier frequency error correction signals with the OFDM signals to correct a carrier frequency of said OFDM signals;
• Fourier transform means for Fourier transforming the OFDM signals whose carrier frequency has been corrected by said carrier frequency correction means, every symbol period, to demodulate information modulated in each sub-carrier to generate frequency domain signals;
• carrier frequency error calculating means for calculating carrier frequency error of said OFDM signals based on said frequency domain signals demodulated by said Fourier transform means and/or on said OFDM signals whose carrier frequency is corrected by said carrier frequency correction means;
• frequency error correction signal generating means for generating said frequency error correction signals based on the carrier frequency error calculated by said carrier frequency error calculating means;
• and
• holding means for finding reliability of fluctuations in said carrier frequency error calculated by said carrier frequency error calculating means when said reliability is found to be low based upon a comparison of a cumulative addition of a plurality of index pulses extracted from said carrier frequency and a predetermined threshold and said holding means outputs the carrier frequency error output from said carrier frequency error calculating means at a pre-fluctuation value without updating.