| 摘要 |
PROBLEM TO BE SOLVED: To attain high speed processing without a PN code generating section by modulating different frequency carriers with a plurality of data and multiplexing the result. SOLUTION: A transmitter side PN code generating section 19 for code spread is provided with PN code generators 15, 16, which generate PN codes (1), (2) of different contents. Depending whether the contents of n-sets of data 12-1 to 12-n are '1' or '0', switches 14-1 to 14-n are used to select the PN code (1) or the PN code (2) and it is used to modulate carriers f1-fn from respective intermediate frequency generators 11-1 to 11-n by code modulators 13-1 to 13-n. A transmitter 17 multiplexes outputs of the code modulators 13-1 to 13-n, the frequencies are up-converted and sent from an antenna 18. At a receiver side, the carriers f1-fn and the PN code (1) the same as those at the transmitter side are used and SAW convolvers 26-1 to 26-n demultiplex data 22-1 to 22-n. |
