Influence Of Noise On System Performance In High Speed Coherent Optical Communication System

Noise is introduced in every subsystem,equipment and fiber link of the coherent optical communication system,so that the performance of the transmission system will be decreased with higher transmission rate and bandwidth.Therefore,it is an important task to study the effect of different noises on the performance of high speed coherent optical communication system.The main works of this article are as follows:1.Simulation and modularization of high-speed coherent optical communication system,debugging and verification of this simulation system.2.The simulation results include the spontaneous radiation noise amplification,laser phase noise,laser frequency noise and the noise is a mixture of various linear noise of coherent optical communication system BER,EVM,OSNR and constellation diagram.3.Simulation study on the effect of mode dispersion on output performance of optical fiber communication system.The main achievements of this paper are as follows:1.The horoscopes of different types of noise are obtained.2.A series of linear noise influence curves such as BER,EVM.OSNR and constellation diagram of coherent optical communication system are obtained,which can be used to determine the noise type of the signal by these rules and constellation features.3.The mode dispersion have a periodic effect on each mode when there is mode dispersion in a few mode optical fiber communication system.The smaller the group time delay is,the longer the period of influence on the system signal EVM is.Nowadays,it is an innovative way to distinguish the linear noise from the regular characteristics of BER,EVM,OSNR and constellation.It is beneficial to distinguish the noise from the system to improve the performance of the optical communication system.In addition,the research will also help to develop the technology of intelligent analysis and diagnosis system damage type,so as to solve the problem of real-time and accurate measurement and analysis of channel in high speed optical fiber communication system.