Analysis of gain difference between forward- and backward-pumped erbium-doped fiber amplifiers in the saturation regime

In saturated erbium-doped fiber amplifiers (EDFAs), signal gain and power conversion efficiency are known to be greater in the backward pumping configuration. This study shows that the difference between pumping schemes is primarily an effect of amplified spontaneous emission. It is concluded that the highest conversion efficiency achievable in highly saturated EDFAs is predicted with fair accuracy by ASE noise-free models, but is approached most nearly with backward-pumped EDFAs.<
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