Design And Implementation Of Data Storage Unit In CBTC System

Communication Based Train Control (CBTC) System is a new trend in the development of railway signal system. Data Storage Unit (DSU) is a core system of CBTC. The function of DSU is to create, maintain and distribute the subway line data. With consultation to numerous documents, industrial standards and practical engineering application data, this thesis hereby designs and implements the DSU system in CBTC.This thesis presents a DSU line model in CBTC, and analyses the key devices and device properties of the model. This DSU line model has high extensibility. Based on this model, the thesis designs and implements the DSU offline and online subsystem. The DSU offline subsystem offers a GUI based method to input raw data in subway projects. After a serial of calculations and validations, the subsystem generates the offline and online data. The DSU online subsystem runs on VxWorks based safe computer; and it maintains and distributes the line data by communicating with other CBTC devices.The DSU introduced in this thesis is used to model a real subway line in laboratory. The line model data is successfully applied to CBTC in lab test. The DSU in this thesis meets the basic requirements of CBTC; Compared to other similar systems available, it has the following distinctive characteristics and advantages:(1) This DSU uses the unified line model and modeling process to assure the consistency of data in CBTC. (2) The DSU offline subsystem has some valuable features, such as data import/export and interlocking table generation. (3) The DSU online subsystem uses an effective flat file format plus various techniques to assure the safety of online data, such as the Elliptic Curve Digital Signature Algorithm.