Modeling, measurement, and a simple analytic approximation for the return loss of erbium-doped fiber amplifiers

An Efficient Simulation Model of the Erbium-Doped Fiber for the Study of Multiwavelength Optical Networks

“…guided as well as the ASE noise terms P L, t , P 0, t to zero. 24 . This is a consequence of the assumption that the ASE self-saturation is negligible.…”