Design And Implementation Of The Expressway Traffic Guidance Information Release System

With the rapid and sustainable development of the economy in our country, there is a huge transport demand for the road, especially the expressway. In order to improve the effective use of expressway, reduce or avoid situations, just like traffic congestion, accident, chaos on the expressway, to build an efficient and automatic system of traffic monitoring and guidance become more and more necessary. The expressway traffic-guidance information releasing system is one of the important components. On the basis of traffic information access, the establishment of expressway traffic-guidance information releasing system can reduce traffic jams, improve the utilization and the road traffic management efficiency.The paper analyzes the current status of traffic guidance system, carries out a detail use-cases studies on the Shandong Expressway traffic-guidance information releasing system. According to actual situation, paper gives a system architecture design including the upper center control system and the underlying communication service system.In communications service system design, a detailed use cases and time-series analysis is given out about polling, control commands for receiving and handling, the scheduling between polling and control. A new polling methods are designed to solve the communication problem between server and field equipment. It shortened the time of polling, avoid the deadlock.In the upper monitor system design, there is a detail analysis and design about factions of system management, electronic map, and equipment monitoring and data control. A new set of control protocol is designed for the difference of the equipment factors. Finally, the system is realized through the technology of serial interface communication, the computer network technology, database technology and electronic map technology etc. At present, the system has been successfully run in Shandong expressway information management center. It is responsible for the information release on the Jing-Hu expressway, Shandong segment. It consists of Dezhou, Jinan, Taian, Zaozhuang four sub-center compositions and has good expansibility.