Comparison of the static and dynamic properties of single- and double-pass partially gain-clamped two-stage L-band EDFAs

We investigate the static and dynamic properties of partially gain-clamped two-stage Lband erbium-doped fiber amplifiers (EDFAs) in single- and double-pass configurations. While both amplifiers can be designed to provide the same gain-clamped performance, the doublepass configuration requires ~40% less pump power and ~22% shorter length of EDF in the second stage, and has a corresponding improvement in power conversion efficiency of 45%, but at the expense of an increase in noise figure (~0.5 dB) and dynamic gain variation.