| 摘要 |
PROBLEM TO BE SOLVED: To distribute frequency spectrum components of an SS modulation wave and to avoid almost spect a of the same frequency all the interference between the band by providing 1st and 2nd spread spectrum modulation transmission sections and spread spectrum modulation reception sections. SOLUTION: A 1st data signal is fed to a 1st SS modulation transmission section 2 from an input terminal 1. The 1st SS modulation transmission section 2 applies modulation to a 1st information signal and applies SS modulation (secondary modulation) to provide the output of a 1st SS modulation wave whose carrier frequency is f1. The 1st SS modulation wave is sent from a transmission reception antenna 4 via a duplexer 3. The sent 1st SS modulation wave is received by a transmission reception antenna 12 and fed to a comb-line filter 14 via a duplexer 11 and a BPF 13. The 1st SS modulation wave passing through the comb-line filter 14 is fed to a 1st reception demodulation section 15, SS demodulation and information demodulation are conducted and a demodulated 1st information signal is outputted to an output terminal 16. |
