Experimental assessment of some Raman fiber amplifiers solutions for coarse wavelength division multiplexing applications

Raman amplification will, in a closer future, penetrate into the access network, bringing new challenges and difficulties to be overcome. In this article, we present the performance assessment of Raman amplification solutions suitable for Coarse Wavelength Division Multiplexing (CWDM) access networks applications. For this purpose, a pumping scheme with three lasers allows a bandwidth of 78nm which is suitable for four CWDM channels. For this scheme, the gain and noise figure dependence with the pumping configuration was evaluated. The gain equalization was experimentally obtained based on a previously developed model using the Genetic Algorithm (GA) for pump allocation. A comparative study of Raman amplification in different types of Raman fibers (single mode fiber and dispersion shifted fiber) is also presented as well as the use of composite links. Those applications were tested in a local network and the obtained results comply with the modeling foreknowledge, showing the feasibility of Raman amplification over CWDM networks.