Modulated signal detection method, optical communication modulation signal detection apparatus, and optical communication system

摘要

PROBLEM TO BE SOLVED: To provide a modulated signal detecting method of accurately detecting a modulated signal from a reception signal which is logarithmically transformed after an optical signal is received in an optical communication system using WDM transmission, to provide a modulated signal detecting device for optical communication, and to provide the optical communication system.;SOLUTION: The modulated signal detecting method comprises averaging the logarithmically transformed signal and extracting a DC component in a step S3; and extracting an AC component excluding the DC component in a step S4. Then they are subjected to reverse logarithmic transform in a step S5 and a step S7 respectively to calculate the power of the optical signal and a relative variation component. In a step S6, one is subtracted from the relative variation component and in a step S8, the result is multiplied by the average power of the optical signal to calculate a pilot tone signal.;COPYRIGHT: (C)2008,JPO&INPIT