Suppression of Dynamic Cross-saturation in Multiwavelength Lightwave Networks with Inhomogeneously Broadened Fiber Amplifiers

With the current surge of interest in multiwavelength lightwave networks [1,2], much attention has focused on the fiber-amplifier cascades they will require. Two serious performance issues have surfaced. First, due to the amplifiers’ non-flat gain spectra, less-favored wavelengths will tend to exponentially decay along the cascade, dropping eventually to undetectable levels. Second, because the amplifiers saturate on a total power basis, adding or rerouting channels in a multi-access network will tend to perturb other signal wavelengths sharing all or part of the route. Although this perturbation will generally be small in a single amplifier, it will grow rapidly along a cascade. Network reconfigurations directly involving a few wavelengths will thus generate both steady-state and dynamic power excursions for all wavelengths.