Patent ID: 9712248
Date: 2017-07-18
CPC Classifications: H04B,H04J,H04L

Claim:
1. An optical transmission device, comprising: an optical splitter configured to input a signal light from a first optical network and having a supervisory signal superimposed thereon, and to branch the inputted signal light into a first branched signal light and a second branched signal light; a variable optical attenuator configured to attenuate the first branched signal light by an attenuation amount, and to output the attenuated first branched signal light for transmission to a second optical network; and a controller configured to detect a modulation component of the supervisory signal superimposed on the signal light from the second branched signal light, and to control, based on the detected modulation component, the attenuation amount of the variable optical attenuator so that the modulation component of the supervisory signal is suppressed in the attenuated first branched signal light output by the variable optical attenuator.