Advances in Erbium-Doped Fiber Amplifiers

Publisher Summary The development of practical Erbium–Doped Fiber Amplification (EDFAs) enabled the development of dense Wavelength Division Multiplexing (WDM) optical networks. These systems, essentially, go beyond single frequency or even multifrequency point–to–point links to dynamic networks that can be reconfigured by add or drop multiplexers or optical cross–connects for meeting varying system demands. It is noted that the WDM networks place new requirements on the EDFAs that include maintaining flatness over many links and recovering from sudden drops or adds of channels. The chapter summarizes recent advances in the EDFA design for high–capacity lightwave communication systems and networks. It provides an insight of means for coping with the challenges often faced with the technique. The chapter illustrates the background material, which includes an introduction to the key EDFA parameters that impact the performance of transmission systems and networks. Furthermore, the chapter illustrates the Raman amplifier, which has drawn considerable attention in recent years because of its superior noise performance. A hybrid amplification design consisting of distributed Raman amplification and EDFA (Raman/EDFA), which has led to significant enhancement in system performance, is also described. The chapter closes with the discussion of advances in the understanding of dynamic phenomena in EDFAs and their impact on optical networks.