Gain equalization in dwdm networks

Abstract

A method of controlling a network () through which information is transmitted in channels (λ, λ, . . . λ) among nodes includes: (a) providing at a node a device () for removing from the network () and replacing on the network () a selected one (λ) of the channels, the device () including a first input port from the network () to the node and a first output port from the node to the network (); (b) taking a measure of the strength (P) of the received channel (λ); (c) regenerating the channel (λ); (d) adjusting () the strength (P) of the regenerated channel (λ) to approximate the strengths of the remaining channels ((λ, λ, . . . λ)-λ; and (e) combining the regenerated and strength-adjusted channel (λ) with the remaining channels ((λ, λ, . . . λ)-λ) at the output port. The method further or alternatively includes (f) calculating an average signal strength (P) for each active channel; (g) establishing a target signal strength (P) for each channel; (h) determining a required change (ΔP) in signal strength; and, (i) sending the node a message to adjust the strength of a signal coupled to the first output port.