| 摘要 |
PURPOSE:To simultaneously supervise a subscriber's line signal by allowing the subscriber's line signal to branch on an optical subscriber's line for connecting a subscriber's terminal and an optical channel, and always inputting it to a detection circuit. CONSTITUTION:A subscriber's line signals transmitted through optical subscriber' s lines 14-16 from subscriber's terminals 01-03 are inputted into branch units 17-19. The branch units 17-19 allow the inputted subscriber's line signals to branch to an optical channel 07 and a signal supervisory part 23 in a state of optical signals. In the supervisory part 23, the subscriber's signals are detected by detecting circuits 20-22 and sent to a signal processor 24. The processor 24 discriminates the subscriber's line signal, based on the input signal, sends a result of discrimination to a control part 25, and the control part 25 sends a control signal to answer trunks 26-28, and sends out a dial tone, etc., to the subscriber's terminal. Moreover, the control part 25 sends the control signal to the optical channel 07, and exchanges the subscriber's line signal transmitted through the optical subscriber's lines 14-16 from the calling terminals 01-03 and the other party terminals 01-03 in a state of an optical signal. |
