Patent ID: 7843630
Filing Date: 2010-11-30
Classification: H01S,H04B

Abstract:
1. A cascaded optical amplifier, comprising: a first optical amplifier and a second optical amplifier in cascaded arrangement, each of the first optical amplifier and the second optical amplifier having a respective input for receiving an optical signal, an output for outputting an amplified optical signal, and a control input for controlling the gain of the optical amplifier; a sensor for sensing upstream of the input of the second optical amplifier a signal relating to operation of the cascaded optical amplifier; a controller for providing control signals to the respective control inputs of the first optical amplifier and the second optical amplifier, the controller providing the control signal to the second optical amplifier as a function of the sensed signal; and a delay introducing element coupled between the output of the first optical amplifier and the input of the second optical amplifier, the sensed signal being sensed upstream of the delay introducing element, wherein the controller delays the sensed signal as a function of the delay introduced by the delay introducing element.