Design of Bidirectionally-Pumped Fiber Double Amplifiers Generating Rayleigh Backscattering
01 January 2002
Optimum pumping schemes for bidirectionally-pumped distributed fiber amplifiers are evaluated that simultaneously minimize the beat noise between signal and amplified spontaneous emission as well as between signal and double Rayleigh backscattering. A way of adding a constraint on signal power to describe operation in a strong Kerr fiber nonlinearity regime is included. We show that one can find an optimum Raman net gain as well as a percentage of forward to total Raman pumping maximizing the signal-to-noise ratio at the end of a transmission line using bidirectionally Raman-pumped transmission fibers.