Evolution behavior of hyperbolic secant pulse in normal and anomalous dispersion regimes of single mode optical fiber communication

We present the results of the investigations of hyperbolic-secant pulse by propagating it through single mode fiber for optical communication. For this purpose, we propagate hyperbolic secant pulse through single mode fiber. Split-step Fourier model is used to implement nonlinear Schrodinger equation that governs the propagation of optical pulse. Results show that for an un-chirped hyperbolic secant pulse, the spread increases by including nonlinearity of the optical fiber in normal dispersion regime. It means GVD and nonlinearity support each other in this regime leading to more pulse degradation. Whereas, results illustrate that these two phenomena compete each other in anomalous dispersion regime, which leads to lesser pulse degradation. These investigations also show that un-chirped hyperbolic-secant pulse experiences lesser pulse degradation in comparison of the initially induced chirp; however pulse spread is more for negative chirp. We further investigated the effect of post-compensation on pulse evolution. The results show very important fact that by using the optimum value of post-compensation, the pulse degradation can be minimized and hence the performance of optical fiber communication can be enhanced significantly.