The characteristics of broadband backward and bi-directionally pumped distributed fiber Raman amplifiers (DFRAs) in hybrid Raman/erbium-doped fiber amplifiers (HFAs) configuration are compared numerically based on noise-nonlinear figure (NNF) when standard single mode fiber (SMF) and non-zero dispersion-shifted fiber (NZDSF) are considered. It is found that achievable NNF in optimized bi-directionally pumped HFAs is about 1.2 dB (or 1.7 dB) higher than that in backward pumped HFAs for SMF (or NZDSF), and better characteristics can be achieved by using NZDSF rather than SMF for long haul transmission.
© 2005 Chinese Optics Letters
Xue Feng, Xiaoming Liu, and Jiangde Peng, "Numerical comparison on the characteristics between backward and bi-directionally pumped DFRAs in hybrid Raman/EDFAs," Chin. Opt. Lett. 3, 257-260 (2005)