Nonlinear interference noise in space-division multiplexed transmission through optical fibers

We study the nonlinear interference noise (NLIN) generated in SDM systems, and generalize the NLIN model introduced in the context of single-mode fibers to the multi-mode case. The generalized model accounts for the modulation-format dependence of the NLIN, and gives the scaling of the NLIN power with the number of transmitted modes. It also provides the tools for extending the results of the NLIN wizard to SDM. Unlike in the case of single-mode systems, the effect of MD cannot in general be ignored in the SDM case. We show that inclusion of MD erases the contribution of FWM effects, and significantly suppresses the effect of XPM.