MOBILE COMMUNICATION SYSTEM AND RECEIVER

PROBLEM TO BE SOLVED: To provide a mobile communication system capable of improving the degradation of the utilizing efficiency of a frequency caused by arranging a guard interval and adopting an orthogonal frequency division multiplex modulation system, and to provide a receiver. SOLUTION: When receiving a wireless signal not including the guard interval, the receiver applies FFT processing to a range including a symbol interval of a processing object and its multipath component, applies frequency equivalent and inverse FFT processing to the signal after being subjected to the FFT processing, and executes the FFT processing for the signal after being subjected to the inverse FFT processing for a range of the symbol interval to demodulate the signal. When receiving a multicast notice signal for informing that data to be transmitted are for multicast transmission, the receiver furthermore extends the object range of the FFT processing. In the case of the multicast transmission, a transmission apparatus transmits a wireless signal with a guard interval of a length predicating unicast transmission inserted thereto, and the receiver extends the object range of the FFT processing so as to space-compose the same signals transmitted from the transmission apparatuses and to capture the composite signal. COPYRIGHT: (C)2008,JPO&INPIT