| 摘要 |
PURPOSE:To enable efficient maintenance by connecting a stand-by optical fiber to one terminal of an optical coupler arranged between an in-use optical fiber and a subscriber customer station transmitter. CONSTITUTION:The subscriber customer station optical coupler 61 is provided between the in-use optical fiber 30 and subscriber customer station transmitter 20 and one terminal of this subscriber customer station optical coupler 61 is coupler 61 is connected as a subscriber customer station in-use line terminal 32 to the subscriber customer station transmitter 20. The subscriber customer station stand-by line terminal 42 of a stand-by optical finder 40 is connected to the other terminal of the subscriber customer station optical coupler 61, i.e., a stand-by line connection terminal 62. Therefore, while a communication is made through the in-use optical fiber 30, the characteristics of the in-use optical fiber 30 and stand-by optical fiber 40 are both measured from either of the in-use line measurement terminal 31 and stand-by line measurement terminal 41 on a station side. Consequently, the operation for the maintenance is reducible to a half as compared with a normal subscriber optical line. |
