An analysis of cross grain saturation effects in systems of cascaded erbium-doped fiber amplifiers

Abstract

Overview: This work addresses the problem of Cross Gain Saturation effects in Erbium Amplifier Cascades. Chapter 1 provides an interesting historical perspective on lightwave communications. This chapter serves as a primer of sorts for understanding the impact of input intensity on amplifier gain, the composition of the erbium-doped fiber amplifier (EDFA) and its importance to optical networking and a discussion of the technique of wavelength division multiplexing (WDM). The chapter closes with a statement of the problem to be addressed in this thesis. Chapter 2 provides background in relating a literature search for characterization of cross gain saturation and techniques currently employed to mitigate this problem. The section contains a condensed list of what is known and unknown about the topic before describing the significance of this study to the area transient analysis. Chapter 3 is a lengthy chapter which describes research methodology for the characterization and observation components of this thesis work. Experimental results from a single stage amplifier and a 4 link amplifier cascade are reported here. Chapter 4 demonstrates a novel all optical mitigation technique for the problem of cross gain saturation in the form of an overpumped amplifier. The theory of overpumping is briefly discussed, and experimental results on single and double stage overpumped amplifiers are reported. Chapter 5 is contains conclusions and an idea of the contributions that this work makes to the field. Additionally was to further this research in the form of future works are discussed.