Patent ID: 11968033
Assignee: FUJITSU LIMITED
Field: Telecommunications (Electrical engineering)
Classification: CPC H | IPC H

Claim 8:
9. A method for controlling optical transmitting power of each wavelength channel of a WDM (wavelength division multiplexed) signal in an optical transmission system that transmits the WDM signal from a first optical transmission device to a second optical transmission device via an optical fiber transmission line, the method comprising:
detecting optical transmitting power of each wavelength channel of the WDM signal by using a first optical channel monitor in the first optical transmission device;
detecting received optical power of each wavelength channel of the WDM signal by using a second optical channel monitor in the second optical transmission device;
calculating a linear SNR (signal-to-noise ratio) of each wavelength channel of the WDM signal based on the received optical power of each wavelength channel detected by the second optical channel monitor;
calculating a non-linear SNR of each wavelength channel of the WDM signal based on the optical transmitting power of each wavelength channel detected by the first optical channel monitor;
calculating a GSNR (generalized SNR) of each wavelength channel of the WDM signal using the linear SNR and the non-linear SNR; and
controlling the optical transmitting power of each wavelength channel of the WDM signal based on the GSNR of each wavelength channel in the first optical transmission device.