Collision-induced pulse timing jitter in a wavelength-division-multiplexing system with strong dispersion management

We develop a perturbation theory to calculate analytically the effects of i nterchannel collisions on Gaussian pulses in a wavelength-division-multiple xed (WDM) system with moderate and strong dispersion management (DM). The l osses are assumed to be balanced by the amplification and are not explicitl y included into the model. We show that, for complete collisions, the colli sion-induced frequency shift of a Gaussian pulse is negligible, whereas for incomplete collisions (those with initially overlapped pulses) this shift is significant. We also show that, as the DM strength increases, the collis ion-induced position shift becomes more important than the frequency shift produced by the incomplete collision. Another result is that the collisiona l shifts depend on the DM strength and the path-average dispersion but not on the lengths of the two fiber segments in the DM cell. We check the fully analytical predictions against direct PDE simulations and find satisfactor y agreement between them. We also give an estimate of the limit imposed on the transmission distance in the WDM soliton systems by the interchannel co llisions. (C) 1999 Optical Society of America [S0740-3224(99)00410-5].