Patent ID: 7415081

Claim:
An orthogonal frequency division multiplex signal reception apparatus for receiving an orthogonal frequency division multiplexed signal consisting of an effective symbol section data and a guard interval section, and to demodulate transmission data, said apparatus comprising: demodulation means for demodulating the transmission data from a portion of the received signal corresponding to the effective symbol section; correlation calculation means for performing an auto-correlation calculation on the received signal to create an auto-correlation signal; and timing control means for generating a control signal to be used to adjust a reception timing of the effective symbol section on the basis of first information extracted from the auto-correlation signal, wherein said timing control means operates to change a speed of adjusting the reception timing of the effective symbol section by changing a response speed of said timing control means itself on the basis of second information extracted from the auto-correlation signal created by said correlation calculation means, the second information being indicative of whether or not inter-symbol interference is generated, and wherein the speed of adjusting the reception timing is controlled so that when the inter-symbol interference is being generated the speed is set at relatively high speed and when the inter-symbol interference is not being generated the speed is set at relatively low speed.