Research And Design On Data Communication Subsystem Of CBTC System Urban Railway Transportation

With the continuous development of the modern cities,the urban traffic congestion is becoming a serious issue.In order to solve these problems,many cities have set up or plan to set up subway to ease the traffic pressure.In recent years,more and more subway lines are using the CBTC(Communication Based Train Control)system.The train-control system based on communication is an advanced train control system that transmits train control information and train state information by continuous and high-capacity bi-directional communication of the vehicle.DCS(Data Communication System)is the core of CBTC system,which realizes the bidirectional information exchange between CBTC system ground equipment and vehicle equipment.When the DCS encounters problems,it may cause traffic problem that affects the regular operation,or even cause an accident.Thus the study of DCS is of great significance.The thesis completes the following work for the CBTC data communication subsystem:In this thesis,the author analyzes the development status of CBTC system and data communication subsystem,and analyzes the status of data communication subsystem in the whole CBTC system.The CBTC system and the data communication subsystem are introduced in this thesis,and the data communication subsystem is analyzed.The importance of the study and the necessity of data communication subsystem are also analyzed.This thesis researches the functions of ATS,ATP,ATO and CI,and researches the composition of CBTC interlocking,ATS,ZC and VOBC,and researches the components of DCS subsystem.Ground backbone network and wireless transmission network should provide the functions and performances.In accordance with the above functional requirements,the thesis discusses the corresponding network composition and design rules for the follow-up DCS to prepare the specific design.This thesis analyzes the network security problems that may exist in the backbone network of DCS sub-system,introduces the network security hidden dangers that may bring about several characteristics of the wireless network.In the view of the above-mentioned security problems,this paper puts forward some suggestions on how to solve the network security problems at the present stage,which helps the program to prepare for the follow-up DCS subsystem security program design.This thesis is based on the Nanjing Metro Air line and discusses the detail design scheme of data communication subsystem wired network,wireless network and network security.The thesis introduces the design of wired network backbone network,the design of wireless network AP point,protocol standard and modulation technology adopted by wireless network,and the handover mechanism and security encryption scheme.The thesis combines with theactual line design and equipment and takes reference to the relevant standards to make the engineering application design.