| 摘要 |
PROBLEM TO BE SOLVED: To stop transmission of a multiplexed optical signal on the occurrence of the break of optical fiber cable or the like without the need for additional hardware so as to prevent a strong optical signal from being emitted from a cut-face of the broken optical fiber cable and to detect the completion of the repair of the broken optical fiber cable to restart transmission of the multiplexed optical signal when the repair is confirmed. SOLUTION: An optical transmission system allows each re-transponder section 7 of each of wavelength division multiplex transmitters 2a, 2b to monitor whether the multiplexed optical signal is supplied through each of optical fiber cables 3a, 3b. The presence/absence of the broken cable in each of the optical fiber cables 3a, 3b and the presence/absence of the restoration are judged on the basis of the monitor result, thereby controlling output stop/output restart of the multiplexed optical signal. |
