| 摘要 |
PURPOSE:To smooth the restoration from an open line by sending an open line detection signal to an opposite optical repeater equipment in place of a data signal from a transmission station of one segment and stopping the data transmission so as to prevent the occurrence of a faulty transmission when the open line of an optical fiber is found out. CONSTITUTION:An open line detection means 7 is provided, which monitors an optical signal from a reception optical fiber D2 and outputs an optical fiber open line signal when an optical signal comes not consecutively for a prescribed time or above and changes over a switch 5 to the position of an open line detection signal generating means 6, and when one of optical fibers D1, D2 is opened, the open line is detected by the open line detection means 7 to send an open line detection signal to an opposite optical repeater equipment C. While the open line detection signal is being sent, the data transmission between both optical repeaters C is intermitted and only the data processing in a segment independently of each segment is attained. Thus, the occurrence of the transmission failure due to the open line of the optical fibers D1, D2 is prevented. |
