Patent ID: 7199920
Filing Date: 2007-04-03
Classification: F01D,H04B,H04J

Abstract:
1. A two-stage optical amplifier comprising at least one input and at least one output, a first stage comprising at least one optical amplifying unit and at least one input and at least one output, a second stage comprising at least one optical amplifying unit and at least one input and at least one output, contacts disposed at a mid-stage between said first and second stages connectable to an OADM, and a local control-communication circuit comprising a control-communication channel between said first and second stages that controls said first and second stages so as to allow dynamic matching of at least one optical characteristic of one of said first and second stages to respective at least one characteristic of the other of said first and second stages, and to prevent automatic shutting down of one of said first and second stages whenever the other of said first and second stages is shut down, wherein the at least one input of the two-stage optical amplifier is connected to the at least one input of the first stage, the at least one output of the two-stage optical amplifier is connected to the at least one output of the second stage, the at least one output of the first stage and the at least one input of the second stage are respectively connected to the contacts disposed at a mid-stage of the two-stage optical amplifier, thereby allowing the introduction of an optical element either between the first stage and the second stage of the two-stage optical amplifier, or between any of the stages of said two-stage optical amplifier and a complementary stage of another similar two-stage optical amplifier, and the control-communication circuit is arranged so as to be selectively configurable either to form the control-communication channel between the first stage and the second stage of said two-stage optical amplifier, or to disconnect said first stage from said second stage while enabling each of the first stage and the second stage to form a separate control-communication circuit and control-communication channel with a complementary stage located on another similar two-stage optical amplifier.