OPTICAL PATH MONITORING DEVICE

摘要

PROBLEM TO BE SOLVED: To monitor the connection of optical space switches for every optical signal by using a pilot signal with a previously assigned fixed frequency and fixing the frequencies of the pilot signal even when optical signal wave length is converted. SOLUTION: The frequencies assigned to respective monitor signal transmitters 11-1 to 11-6 are fixed and made invariant even when the wave lengths of the optical signals for superimposing them are converted and the whole frequencies of the pilot signals to be superimposed with the optical signals which are inputted to the respective optical space switches 13-1 and 13-2 are made to be different. The optical signals with which the pilot signals are superimposed are respectively switched to prescribed optical transmission paths with the optical space switches 13-1 and 13-2. The optical signal S2(λ1) from a transmitting device 12-2 is outputted from a confluent equipment 32-1 which is connected to the optical transmission path 13-1 with a 1×2 optical switch 31-2. Then, the optical signal S2(λ1) is inputted to a connection monitor circuit 42-1 with a branch equipment 41-1 and the pilot signal PTs(f2) to be superimposed with the optical signal is detected.