Evaluation of nonlinear phase noise in DPSK transmission for different link designs

We analyzed the impact of nonlinear phase noise caused by Gorden-Mollenauer effect in single-channel return-tozero differential phase-shift-keying (RZ-DPSK) transmission in dependence of system bit rates, dispersion compensation schemes and different fiber types. The investigation is reported by simulating RZ-DPSK signals for 3200 km, taking into account penalties in Q-factor induced by nonlinear phase noise. From these simulation results, higher bitrate systems, system with pre-compensation schemes and system using stand single mode fiber transmission are more robust against nonlinear phase noise. Furthermore, by looking into the standard deviation of the signal intensity and phase for all sampling points within one-bit duration, we observed that optical noise can be washed out from the bit center during propagation.