Patent ID: 7526011

Claim:
A radio communication system having a radio transmitter and a radio receiver and adopting multiple carrier modulation and code spreading modulation methods, comprising: a selecting unit provided in the radio transmitter or the radio receiver, for selecting an interleaving mode out of a plurality of interleaving modes depending on radio propagation path conditions; a symbol configuration unit provided in the radio transmitter; and a symbol reconfiguration unit provided in the radio receiver, wherein the symbol configuration unit configures information symbols to be transmitted by the radio transmitter in both time and frequency directions in a pattern according to the interleaving mode selected by the selecting unit, the symbol reconfiguration unit reconfigures information symbols received by the radio receiver in both time and frequency directions in an inverse pattern of the pattern, the selecting unit selects an interleaving mode based at least one measured result of maximum Doppler frequency and delay spread characteristics in the radio propagation paths, when the selecting unit selects an interleave mode based on the measured result of the maximum Doppler frequency in the radio propagation paths, the selecting unit selects a bit interleaving mode or a symbol interleaving mode when the maximum Doppler frequency is larger than a predetermined value, and a chip interleaving mode when the maximum Doppler frequency is smaller than the predetermined value, and when the selecting unit selects an interleave mode based on the measured result of the delay spread characteristics in the radio propagation paths, the selecting unit selects the bit interleaving mode or a symbol interleaving mode when the delay spread is larger than a predetermined value, and the chip interleaving mode when the delay spread is smaller than the predetermined value.