A Study on the Effects of Dispersion and Nonlinearity in Optical Fiber Communication Systems using DCF

-In modern optical fiber communication systems, dispersion and nonlinear effect of optical fiber are the two main factors of decreasing communication quality, especially in Group Velocity Dispersion (GVD). In this paper, we use single-mode transmission fiber, Dispersion Compensation Fiber (DCF) and erbium-doped fiber amplifier (EDFA) to design a dispersion compensation optical fiber communication link. In optisys software, we simulate the 4QAM optical fiber communication system which based on this communication link. Through the diagram of constellation of receiving single, we study the influence of group velocity dispersion, nonlinear effect, amplify spontaneous emission (ASE) respectively, and their mutual effects to the quality of the signal in communication system. The results shows that dispersion compensation can only remove the influence of group velocity dispersion, but the nonlinear phase noise, which caused by the mutual effects of nonlinear effect and amplify spontaneous emission, will be accumulated as the increasing of fiber length and influencing the quality of 4QAM optical fiber communication system.