Study On Data Exchange Standard Of Urban Traffic Signal Control System

Urban traffic signal control system play an important role in solving the traffic jam and guaranteeing traffic unblocked, as well as in keeping good traffic orderliness. Researching standardization and specification of the traffic signal control system is a good solution to system construction, development and saving money in the process of the intelligent traffic signal control system implementing. At present, we had constructed the urban traffic signal control system through introducing foreign proprietary system. We need to buy proprietary center device and field controllers because of protocol bulwark in the course of system construction, these way has caused some problems. First of all, we don't introduce the competitive mechanism into the system implementing. Furthermore, the system also lacks interoperability and interchangeability. Therefore, the thesis put forward establishing a data exchange standard of the traffic signal control system to solving above mentioned problems in our country. Firstly, this thesis reviewed the previous study all over the world and summarized the characteristics of eXtensible Markup Language. The paper also discussed the XML application in transportation and put forward the design principle, design flow and implementing process of traffic markup language based on XML. Secondly, the paper analyzed several foreign traffic signal control system used in our country and summarized the data exchange content, data structure and data format between traffic control center and field controllers, as well as traffic control center and other traffic center. The paper also analyzed the applicability of XML in traffic signal control system. What's more, the structure and format of traffic signal control data dictionary was established, it provides the basis of the tag's name and data type in data exchange standard. Thirdly, in terms of the aforementioned requirements and system's trend of data exchange standard, the thesis established the general data exchange standard named SignalML ver0.1, which is traffic signal control markup language. Furthermore, the paper discussed the principle and goal of designing SignalML. The whole tree-framework and detailed sub-framework of SignalML, which consisted of basic information layer, device information layer, timing plan layer, detector parameter layer, telnet control layer, intersection MOE layer and user management layer, was designed. The SignalML Schema, which coded using the xmlspy software, provided a basis for interconnecting and interoperability between traffic control center and different type of controller. In the end, according to the trend of urban traffic signal control system and adopting web service technique, the paper developed the intersection online system based on SignalML, then made a test that the system communicated with the communication board in some functions, the test result showed some validities and rationalities of SignalML.