Transmission Performance Of Coherent Detection In-band Label Switching System

Due to the explosive development of Internet,optical transport network(OTN)which plays an important role in optical fiber,is rapidly developing.Currently,OTN requires high transmission speed,and it drives technology of optical communication to carry on.The aim of future optical fiber communication is all optical network(AON).Current optical network requires optical repeaters in the case of long-haul transmission.The processing procedure in optical repeaters and optical switching nodes contains a process called“optical-electrical-optical”(OEO).OEO procedure constrains transmission speed of OTN.Therefore,people need to find a new way to achieve a higher transmission rate of optical network.Optical label switch(OLS)is one promising solution.It uses optical labels to carry routing information instead of electrical labels.Payload carries data while label carries routing information.This thesis mainly studied optical label switching technology,analyzed coherent detection in-band label switching system,and built 40 Gb/s ASK/ ASK and 40 Gb/s DPSK/ASK in-band label switching network transmission system,then analyzed and optimized the system structure in optical simulation software.The thesis contents include:(1)Introduced the research background and optical label technology and its development status.(2)Introduced the optical modulation and demodulation technology.The basic format of optical modulation used in the system of coherent detection optical label switching technology—ASK,PSK,studied and analyzed optical modulation key device—Mach-Zehnder modulator.In addition,this thesis focused on the two demodulation techniques,direct detection and coherent detection.(3)The thesis built 40 Gb/s ASK/ASK and 40 Gb/s DPSK/ASK in-band optical label simulation system,optimized the system parameters,analyzed the influence of each device on the optical label switching system.Finally,the transmission performance of the system is analyzed.(4)Improved the existing single node in-band label system structure,the thesis built 40 Gb/s ASK/ASK and 40 Gb/s DPSK/ASK multi-nodes in-band optical label switching simulation system based on the principle of tag stack routing,studied and analyzed the influence of each device on the optical label switching system,including the laser linewidth,the optical filter and the influence of the transmission distance.Finally,the thesis optimized parameters of the system according to various factors,gived optimal transmission characteristics of the optical label switching system,and verified the feasibility and effectiveness of the program.