Logic Design Of Overhead And Research Of Alarms In Optical Transport Network

The advent of information industry forges the great development of Internet,and also an optical network based on WDM technology has been pursued widely in telecommunication industry, which has severl advantages such as large capacity, high rate and high performance management.As a transport network, optical network plays a critical role in modern society. In recent years, IP over WDM which is the combination of the two is well received by communication industry; meanwhile, The Optical Transport Network (OTN) becomes a popular technology to implement this solution of IPoWDM. OTN technology is the compromise production between the electronic network and all optical networks;it transplants the strong and perfect OAM&P idea and function of SDH to the WDM optical network, making up the defect of current WDM system in performance surveillance and maintainance. Based on the current development state of OTN, the International Telecommunication Union(ITU-T) proposed G.709,which defines the mapping, multiplexing and overhead of client signals,overhead is the core of this protocal.However, how to implement the insertion and extraction of overhead in Optical Transport Network with a cost-effective way to improve OAM&P for optical channels becomes one of important academic research topics.Due to the development of electronic technologies and the advent of advanced tools of EDA (Electronic Design Automation),we do not need more expertise about hardware circuit for FPGA design.In addition to the traditional method by hardware logic circuit, we can also use Verilog HDL (Hardware Description Language) for FPGA design,it is very convenient and flexiable.Thus FPGA has wide range of application in the field of communications.This dissertation is based on the project of "Development of High-capacity OTN Switching Technology and Equipment System" supported by National High Technology Research and Development Program of China.The main innovation points of this dissertation are listed as following:1.The clear research and analysis about OTN are finished, and then an OTN overhead system design and simulation have been implemented;2.A detection method of frame synchronization is presented based on OTN frame structure, which lays a significant foundation of subsequent process for other effective data; 3.A simulation platform for the system has been designed which completes the verification of the OTN overhead system.4.A patent for the simple method of overhead insertion for Opical Data Unit in optical transport networks has been submitted.