Radio communication system and transmitting apparatus used for the same

摘要

To provide a system that can accommodate a greater number of terminals within a limited band and can obtain a higher transmission rate. While the number of frequency signals (spectrums) output in parallel by performing a spread spectrum from the DFT unit of each terminal is 12, the number of sub-carriers constituting one sub-channel is set at 10 or 11. In this case, the users (users A and G) allocated to the sub-channels at both ends of the band will not perform transmission of one frequency signal at the end (one sub-carrier) of all the frequency signals output from the DFT unit, whereas the users (users B to F) allocated to the other sub-channels will not perform transmission of the frequency signals at the ends (two sub-carriers). This transmission can be realized by deleting (clipping) the associated number of signals from both ends or from one end of the frequency signals output from the DFT unit of each terminal and allocating the frequency signals after clipping, to individual sub-channels.

主权项

1. A radio communication system comprising:
a transmitting apparatus that generates a first spread spectrum signal by performing a spread spectrum of a time-domain information signal and transmits the spread spectrum transmitting signal with allocating the spread spectrum transmitting signal to any one of a plurality of contiguous frequency channels defined in a constant frequency band formed of a plurality of sub-carriers and to any one of a plurality of time channels defined as having a constant time length; and a receiving apparatus for receiving the transmitting signal, wherein the number of sub-carriers N that constitute one of the frequency channels is previously set so as to be lower than the number of sub-carriers M that constitute the first spread spectrum signal, the transmitting apparatus generates a second spread spectrum signal, which is constituted by the N sub-carriers, by deleting the (M−N)/2 sub-carriers at both ends of the first spread spectrum signal in order to allocate the transmitting signal to a frequency channel and transmits the second spread spectrum signal, and, the receiving apparatus receives the transmitted signal from the transmitting apparatus and performs a reproducing process of the time domain information signal to be noticed by the first spread spectrum signal, based on the received signal, wherein the time domain information signal is sent by the M sub-carriers is noticed using the frequency channel formed of the N sub-carriers.