| 摘要 |
PURPOSE:To detect a circuit fault of a master station, by multiplexing in time division a monitor signal and applying to a transmitting signal within a master station having a time division multi-direction multiplex communication system which transmits the signal to a master station from a slave station with a single frequency, then branching the multiplexed signal to the receiving side of the master station to monitor the monitoring signal. CONSTITUTION:For a master station device, a signal (b) supplied from a circuit 11 which generates a signal for monitor of own station device is multiplexed to a signal (a) which is transmitted to a slave station through a time division multiplexing circuit 12. The output (c) of the circuit 12 receives the signal processing such as scrambling, etc. through a circuit 13. The signal output (d) is modulated by a modulating circuit 14 and converted into an IF signal (e) which is transmitted to the slave station. A part of the signal (e) is branched, and only the modulated signal (f) of the monitoring signal (b) is extracted through a gate 15 and gransmitted to the master station from each slave station through the next circuit 16 to be multiplexed with time division with a signal (g) of a single frequency which received a frequency conversion into the signal (e). This multiplexed signal is demodulated by a demodulating circuit 17 and receives the signal processing through a signal processing circuit 18. Then signals (g) and (b) are reproduced, and a signal (j) is delivered. The signal (b) is monitored by a monitoring circuit 19 to detect the fault of circuits 12-18 of the master station device. |
