| 摘要 |
PURPOSE:To send a signal other than a control signal required for the control of outgoing/incoming call by a weak power by applying controlling the transmission power of a control channel so as to be reduced thereby decreasing the effect of common use of the control channel with other transmission/reception device. CONSTITUTION:The control system is constituted so that a high frequency signal of a modulator 11 is attenuated by providing a power reduction circuit 21 formed by a variable high frequency attenuator. Through the constitution above, when the transmitter/receiver is in the standby state in the control channel, the power reduction circuit 21 is operated by the control of a controller 15 and an identification signal or a zone identification signal or the like of the transmitter/receiver is sent continuously or intermittently during this time. On the other hand, in sending the control signal at the outgoing/incoming call to/from the mobile body, the power reduction circuit 21 is inactivated and the signal is sent at a specified output. Thus, the effect of the common use of the other transmitter/receiver in the control channel is reduced and the signal other than the control signal required for the control of the outgoing/ incoming call is sent by a weak power. |
