| 摘要 |
PURPOSE:To realize a repeating system for single-wave press-to-talk communication by modulating and sending a circuit signal with the 1st low frequency signal at a transmitting station and by modulating and sending the circuit signal of the same frequency with the 1st and 2nd low frequency signals at a repeater station. CONSTITUTION:In radio equipment 11, a circuit signal of frequency f1 generated by circuit frequency oscillator 157, modulator 156 and multiplier 155 under the control of control part 160 is modulated with tone signal F1 from oscillator 158 and then amplified by the power amplifier before being transmitted intermittently. In repeater 12, it is received by receiver 151' to detect 153' signal F1 and a prescribed time later, tone signal oscillators 158' and 161 are operated simultaneously to modulate and transmit the circuit signal of frequency f1 with signals F1 and F2 through modulator 162, multiplier 155' and amplifier 154'. In radio equipment 11, the signal modulated with tone signals F1 and F2 is received to make sure of the reception of the signal sent from its station by the repeater and radio equipment 11', on the other hand, can make sure that the received signal is an indirect received signal via the repeater. |
