Patent ID: 7672042

Claim:
An optical fiber amplifier that supports a plurality of optical signal channels, comprising: at least one optical pump, each optical pump injecting optical power into an optical fiber at an assigned pump frequency; a partitioning unit that partitions the plurality of optical signal channels into at least one wavelength region and that provides an indication of a corresponding power variation for one of the at least one wavelength region; a control unit that determines a corresponding pump power adjustment for one of the at least one optical pump using a predetermined function, the predetermined function relating the corresponding power variation for said one of the at least one wavelength region to the corresponding pump power adjustment for said one of the at least one optical pump, said one of the at least one optical pump adjusting a corresponding power output in accordance with the corresponding pump power adjustment, wherein the predetermined function corresponds to a linear relationship between the corresponding pump power adjustment and the corresponding power variation of said one of the at least one wavelength region, wherein the partitioning unit comprises: a coupler that obtains coupled optical signals from the optical fiber, the coupled optical signals having a portion of a total power of the optical signal channels; a 1 by K band wavelength-division multiplexer (B-WDM) that partitions the coupled optical signals into the at least one wavelength region, wherein K is an integer greater or equal to one; and at least one photodetector that provides the indication of the corresponding power variation of said one of the at least one wavelength region, wherein 1. the optical fiber amplifier comprises a backward-pumped optical fiber amplifier, 2. the partitioning unit is situated at a first geographical location, and 3. the at least one optical pump is situated at a second geographical location, the optical fiber amplifier further comprising: a communication channel that conveys control information from the first geographical location to the second geographical location to control the at least one optical pump.