Patent ID: 6956812

Claim:
A reception apparatus for receiving an orthogonal frequency division multiplexed (OFDM) signal having, as a unit for transmission, a transmission symbol including an effective symbol generated on dividing the information into respective frequency components in a predetermined range and a guard interval generated on copying the signal waveform of a portion of said effective symbol, comprising: means for setting one or more of a time interleaving pattern, carrier modulation scheme and a convolutional code; Fourier transform means for extracting a processing range corresponding to a period of said effective symbol from said transmission symbol and Fourier transforming the extracted processing range to demodulate the information; window control means for controlling the said processing range; input means for a user to input the selective inputting information for selecting the OFDM signal to be received; means for detecting transmission control information; storage means for storing information on the length of said guard interval in association with said selective inputting information input by a user; and control means for reading out said information on the guard interval length responsive to the selective inputting information as input and for providing the guard interval length information thus read out to said window control means and for providing the transmission control information to the window control means; wherein said window control means controlling the processing range, at the time of starting the reception, based on the guard interval length information and the transmission control information provided by said control means, thereby minimizing an initial rise time from a start of reception until output.