The Micro-Theory of Erbium-doped fiber amplifiers

摘要

1 Introduction Erbium-doped fiber amplifiers have the advantages of high gain,wide band,high output power and low noise figure,etc.,they have been studied extensively on theory model and design[1-2].To obtain performance evaluation and design criteria for transmission system,an accurate statistical characterization of the optical amplifiers is needed in terms of both signal gain and quantum noise. Unfortunately,because of the complexity of the involved phenomena,most of papers do not present models which prove to be sufficient for an adequate analysis of transmission systems. Rate equations or semi-classical theory are used for usual analysis of optical amplifier ,and for the analysis of ASE noise,equivalent band or separate equivalent band is used,which ASE noise of different separate is treated as white noise with different intensity. These oversimplified characterizations are insufficient to obtain accurate performance evaluation and to furnish correct parameters design for optical communication systems.