| 摘要 |
PROBLEM TO BE SOLVED: To monitor an abnormality of the engagement of an optical connector, etc., in an optical subscriber accommodation device which accommodates multiple optical subscriber devices in a passive double star constitution. SOLUTION: A transmit signal process part 1 of the optical subscriber accommodation device generates a down signal to be sent out to an optical subscriber device and the signal is sent out as a down light signal through an electrooptic conversion part 2 to the optical subscriber device by an optical coupler 3 through a transmission line of an optical fiber. A light signal branched from the optical coupler 3 is converted by an optoelectric conversion part 4 into an electric signal, which is sent out to a receive signal process part 5 and a reflected signal detection part 6. The reflected signal detection part 6 detects whether or not the light signal is received in the timing where it is not received in a normal state, and outputs an alarm signal when the light signal is received in the abnormal timing. With the light signal sent from the optical subscriber accommodation device, a reflected signal of the optical connector of the optical subscriber accommodation device, an optical demultiplexer, the optical subscriber device, etc., are detected to output the alarm signal. |
