TRANSMISSION DEVICE, TRANSMISSION SYSTEM, AND FAULT DETECTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a transmission device that effectively detects a fault in a reserve system, a transmission system, and a fault detection method.SOLUTION: A transmission device includes: a plurality of first output units which are respectively connected to a plurality of transmission channels branching off from one transmission channel and which alternatively output signal light to the plurality of transmission channels; a second output unit which outputs inspection light having a different wavelength from the signal light to one of the plurality of transmission channels; and a detection unit that detects faults in the plurality of transmission channels on the basis of results of detection of reflected light of the inspection light input from at least one of the plurality of transmission channels.