Optimizing the EDFA gain for WDM lightwave systems

Abstract

Optical amplifiers play a vital role in Optical Fiber Communication Systems as they are used to compensate the total optical signal attenuation along the transmission path and hence permit to build optical fiber communication systems of very long distances without using repeaters and signal regenerators. However, in modern WDM (Wave Division Multiplexer) systems where several optical carriers of different wavelengths (or frequencies) may share a single fiber, the Erbium Doped Fiber based amplifier (DFA), one of the most commonly used type of amplifiers, shows non-uniform gain characteristics with respect to the carrier frequency. In addition, The default parameter values used to carry out system analysis using simulation tools do not necessarily give accurate results. The objective of this work is therefore to conduct a study and an analysis of the EDFA to show first its behavior when used in WDM systems and estimate the best frequency range (operating band) of use and, second to estimate better (optimal) parameters values that should be used with a simulator (Optisystem) to obtain more reliable analysis of WDM transmission systems rather than default ones provided by the software.