Patent ID: 7889802

Claim:
A demodulating apparatus that receives a signal modulated with the orthogonal frequency division multiplexing (OFDM) technique and demodulates the modulated signal, the demodulating apparatus comprising: an orthogonal demodulating means for making orthogonal demodulation of the modulated signal to generate a complex signal including real- and imaginary-axis components; a complex-conjugate signal generating means for generating a complex conjugate signal of the complex signal produced by the orthogonal demodulating means; a delaying means for delaying, by an integral multiple of a predetermined period, the complex conjugate signal generated by the complex-conjugate signal generating means; a complex multiplying means for making complex multiplication on the basis of the complex signal generated by the orthogonal demodulating means and complex conjugate signal delayed by the integral multiple of the predetermined period by the delaying means; a determining means for determining whether an interference wave is included in the modulated signal by making a comparison between the complex multiplication value resulted from the complex multiplication made by the complex multiplying means and an arbitrary threshold; and an interference wave canceling means for canceling an interference wave from the modulated signal on the basis of the result of determination from the determining means.