| 摘要 |
PURPOSE:To effectively utilize transmission capacity with a station side transmitter and to improve economics by setting a common test channel usable in common by plural subscriber side transmitters and constituting a test link. CONSTITUTION:During a transmission period, from the station side transmitter 40 to the subscriber side transmitters 6-1 to 6-N, the corresponding information channels and test channel B1-1 to B1-m, B2-1 to B2-m. BN-1 to N-m and the test channel S are multiplexed and transmitted. When a fault is generated in a channel 1-1 and a channel test is required, a testing circuit 9 sets the test link, that is the test channel S, with the transmitter 6-1 through the TDMA circuit 41 of the transmitter 40 and transmits control information for testing wiring to a customer station equipment to the transmitter 6-1. The testing circuit 9 of the transmitter 6-1 performs a customer station wiring test from the INF circuit 4-1 of the fault channel 1-1 to the customer station equipment. A test result is performed by using the test channel S and when the test is completed, the set test link is released and the test channel S becomes free. |
