Patent ID: 7317570
Filing Date: 2008-01-08
Classification: H01S,H04B

Abstract:
1. A variable gain optical amplifier comprising: amplifying means for amplifying optical signals at different wavelengths in a fiber-optic communications link, the amplifying means being in the form of a pump driver for optically pumping an optical fiber to provide optical gain; input power detection means for monitoring the power P output power detection means for monitoring the power P gain control means for supplying a drive signal to the pump driver to control the optical gain; feed forward means for supplying a feed forward signal to the gain control means dependent on the monitored input power P feed back means for supplying a feed back signal to the gain control means dependent on the monitored output power P wherein the feed back means comprises an adaptive proportional-integral (PI or PID) controller for controlling the optical gain at a required gain set point in accordance with proportional and integral control coefficients K