| 摘要 |
PURPOSE:To make it possible to detect a fiber break point in real time by leading supervisory signals, generated by two break-point orientation units, to a light repeater, by making a supervision over the break of supervisory signals, and by transmitting and receiving obtained information by those orientation units. CONSTITUTION:Light repeater 8 operates through remote or local electric power feed, but even if an fiber is broken causing the break of electric power feed, terminal stations A and B can detect the interruption of supervisory signals since the signals propagate earlier than the functions of light repeater 8 are disabled due to the break of power feed, so that orientation to a break point can come into effect. Thus, supervisory signals generated by break-point orientation units 4 and 5 are led to main repeater 9 and subordinate repeater 10 and pieces of information Ta and Tb on a supervision over those supervisory signals are transferred between break-point orientation units 4 and 5 via separately provided control circuits, so that the break point of the fiber can be detected in real time. |
