06900931 is referenced by 5 patents and cites 23 patents.

A three stage optical amplifier is disclosed having a substantially flat gain profile. The amplifier includes a variable optical attenuator coupled between second and third stages of the amplifier and a dispersion compensating element. The attenuation of the optical attenuator is adjusted in accordance with the loss across dispersion compensating element and the optical power input to the amplifier to thereby obtain a substantially flattened gain profile. An offset value can also be used to refine the variable optical attenuator control and minimize nonflatness. The first and second stages are preferably pumped to provide high gain and a low noise figure and the third stage is preferably pumped to provide a high optical conversion efficiency. In an additional example, received optical powers associated with each of the channels in a WDM system are monitored and the attenuators within each amplifier in the system are controlled so that the received powers are substantially equal.

Title
Three-stage optical amplifier having flat spectral gain
Application Number
9/677344
Publication Number
6900931 (B1)
Application Date
October 2, 2000
Publication Date
May 31, 2005
Inventor
Jun Bao
Ellicott City
MD, US
Michael G Taylor
Laurel
MD, US
James E DeGrange Jr
Glen Burnie
MD, US
Clark Scrandis
Columbia
MD, US
Balakrishnan Sridhar
Ellicott City
MD, US
Agent
Michael R Cammarata
Assignee
CIENA Corporation
MD, US
IPC
H04B 010/17
H01S 003/00
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