Patent ID: 7158728

Claim:
An optical repeating system comprising: an uplink optical transmission line; a downlink optical transmission line; optical transmitters and optical receivers for transmitting and receiving a main signal via at least one of the uplink and downlink optical transmission lines; and a plurality of grouped optical amplifying repeaters each installed at an intermediate position on the optical transmission lines for amplifying and repeating the main signal with optical amplifiers, wherein at least one of said optical transmitters specifies a group of at least two of said plurality of optical amplifying repeaters, and transmits a supervisory command to of optical amplifying repeaters in the group as a first sub-signal, the supervisory command commanding to supervise internal circuits of said optical amplifying repeaters in the group, and wherein said optical amplifying repeaters in the group each transmit, when receiving the supervisory command addressed thereto via one of the uplink and downlink optical transmission lines, a supervisory signal indicating supervisory result corresponding to the supervisory command to said optical receivers as a second sub-signal via said uplink optical transmission line and said downlink optical transmission line, and when specifying said group, one of said optical transmitters superimposes on the main signal a unique group identifier, and wherein each of said plurality of optical amplifying repeaters in the group store the unique group identifier in advance, and make a decision that they themselves are specified when they detect the unique group identifier in the main signal.