RADIO COMMUNICATION EQUIPMENT

摘要

PURPOSE:To provide the radio communication equipment whose ciphering performance is much more enhanced by changing a subcarrier frequency used for frequency modulation. CONSTITUTION:This radio communication equipment is adapted the ciphering system by inversion of the frequency spectrum by transmitting only the lower side band after frequency modulating to a voice signal with a subcarrier frequency. And a control circuit 30 outputs a subcarrier frequency varied automatically at an optional time interval according to a program of a microcomputer 31 at transmission and outputs the frequency control signal together with a voice signal subject to frequency modulation by the subcarrier frequency. function the control circuit 30 outputs the subcarrier frequency of the same frequency and the same phase as those of the subcarrier frequency of the sent signal based on the frequency control signal included in the signal extracted by a detection circuit 25 at the reception.