Patent ID: 7554718
Filing Date: 2009-06-30
Classification: H01S,H04B

Abstract:
1. A method for controlling a gain of a Raman fiber amplifier having M Raman pumps in an optical fiber system that is responsive to N optical signal channels, the Raman fiber amplifier having a feed-forward control configuration, the method comprising: (a) determining an input signal power variation for at least one wavelength region, the N optical signal channels being with the at least one wavelength region; (b) determining a pump power adjustment for each Raman pump of the Raman fiber amplifier with a feed-forward control configuration using a predetermined function, the predetermined function depending on the input signal power variation and having parameters that are independent of a dynamic loading of the optical fiber system; and (c) adjusting each Raman pump in accordance with the pump power adjustment, wherein the predetermined function corresponds to a linear relationship between the pump power adjustment and the input signal power variation of the at least one wavelength region, the predetermined function comprising: wherein k corresponds to a k th wavelength region, wherein j corresponds to a j th Raman pump, ΔS L (k) corresponds to the input power variation for the k th wavelength region as linearly scaled, ΔP L (j) corresponds to the pump power adjustments of the j th Raman pump as linearly scaled, and T LL (j,k) corresponds to a linear coefficient relating the pump power adjustment of the j th Raman pump and the input signal power variation for the k th wavelength region.