OPTICAL TRANSMISSION DEVICE AND OPTICAL TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To prevent the quality degradation of optical signals of individual modulation systems in a WDM transmission system that uses optical signals of different modulation systems.SOLUTION: An optical transmission device includes: a reception unit for receiving a WDM signal including a first optical signal generated by a first modulation system, and a second optical signal generated by a second modulation system having a multi-level number smaller than the first modulation system; an attenuation unit for attenuating power of the first optical signal to a first target level, and attenuating power of the second optical signal to a second target level which is lower than the first target level; and a transmission unit for transmitting a WDM signal including the first optical signal and the second optical signal which have been attenuated by the attenuating unit.SELECTED DRAWING: Figure 11