Research And Simulation Of Optical Network Performance In Optical Fiber Communication Systems

With the rapid development of the Intemet service and multimedia applications,network traffic is growing at an exponential speed, which requires cross-ability of thenetwork must have high bit rate data transmission capacity and throughput. The emergenceof optical fiber communication technology began to permeate the entire communicationnetwork and progress forward push the all-optical network. The40Gb/s optical fibercommunication system has been deployed fully commercially and100Gb/s orhigher-speed optical fiber communication system is also expected to become practical inthe near future.At present, one of the major technical bottlenecks of all-optical network is thedevelopment of monitoring technology. How to obtain the performance status of theoptical channel to support network control and management is still a critical problem in theoptical communication equipment and system design. The optical performance monitor(OPM),a precise, light-weight and low-cost monitoring module can meet the demands ofnetwork.Its main role is to monitor each optical channel wavelength, power and opticalsignal to noise ratio (OSNR) in the network. OSNR is an important parameter to measurethe performance of the optical channel.There are many parameters will be measured by OPM. In this paper, we focus on theOSNR and its measurement method. Firstly,we take an overview of the current commonmethods of OSNR, including out-band and in-band OSNR measurement method.Weanalyze their measurement principles, applicable conditions, as well as the problems andshortcomings;Then,we propose a differential spectral response method, also analyze themeasuring principle; Finally, we simulate and analyze three OSNR measurement methodsoutband interpolate,inband signal-off and differential spectral response in Optisystem.This thesis is mainly summarizing different optical signal-to-noise ratio (OSNR)measurement methods of OPM,analyzing the pros and cons of various methods and theapplicable conditions, and simulating three different OSNR measurement methods, as wellas we propose improvements, at last we conclude our work and present some problems wemet and hope this may have significant value for further OSNR measurement methodresearching.