METHOD AND SYSTEM FOR STABILIZING TRANSIENT PHENOMENON CONTROL IN LIGHT AMPLIFICATION NETWORK

摘要

PROBLEM TO BE SOLVED: To provide a system and a method for controlling reactions with respect to a power transient phenomenon in a wavelength division multiplex(WDM) network, whose signal is optically amplified during network reconfiguration or on the occurrence of a failure, when a WDM channel is added or deleted. SOLUTION: A variable band width filter circuit 500 is operated by a first prescribed band width for a first period τ0 to detect a change (power transient phenomenon) in a signal power caused by an event of a transient phenomenon and operated by a second specified band width narrower than the first prescribed band width for a period τ0+Δτ after the lapse of the first period to nearly suppress a low level signal change such as a remnant of the power transient phenomenon. Thus, the actual power transient phenomenon is maintained to start amplifier gain control based on the change in input power while the remnant is eliminated by preventing the remnant from being interpreted in mistake as an actual transient phenomenon event phenomenon.