High bit rate communication systems using non-linear effects

Abstract Calculations are presented on the non-linear Schrodinger equation in the presence of loss. This equation describes the propagation of optical pulses in a non-linear waveguide in the anomalous dispersion regime. The calculations are performed for realistic fibre parameters over 15 km. The results indicate that it is necessary to generate higher order solitons in order to obtain any advantage from the non-linear effects in the material. We also show that including loss as a perturbation is only valid for short fibre lengths or very low losses and that the conclusions of Hasegawa and Kodama (1981) are not necessarily appropriate for all fibre systems.