Research And Development Of Public Vehicle Information Release System Based On Beidou System And 3G Network

With economic development and technological progress, especially mobile internet and BDS(BeiDou System) having been improved greatly, the public transportation information issuing system based on BDS and mobile internet technologies has become a hot spot of current research.The public transportation information issuing system relieves the traffic pressure, improves the intelligent level of city management, and promotes the application of BDS which belongs to our country. The key and difficult points of the public transportation information issuing system include the automatic bus-station reporting algorithm and the reliable real-time data transmission between the public information issuing system and its remote control center. To report the station correctly, the most current automatic bus-station reporting algorithm needs manual intervention. Moreover it can’t report correctly if the bus turn around randomly. On the other hand, there is few reports that 3G communication devices support USB bus, based on non-operating system. Current solutions are most based on Linux operation system, which brings about greater hardware consumption to the whole system.The Beidou positioning and 3G network communication technologies are used in the thesis, to design and develop a public transportation information issuing system. A new kind of automatic bus-station reporting algorithm is also put forward. The design of USB driver, with host based on STM32F107 x and slave based on 3G device EM770 W, is realized. The main work and achievements of the thesis are as the following:(1) The public transportation information issuing system based on BeiDou system and 3G communication is designed. The hardware and software design of the system is realized. In the software mechanism, a new task management system is researched and realized, which is similar to uC/OS-II’s task management system. Adding or deleting functions are realized by adding or deleting tasks. Thus, the scalability, stability and robustness of the software are greatly enhanced.(2) A new type of automatic bus-station reporting algorithm is proposed and developed, which is based on the designed positive sequence circular chain table. This algorithm solved the problems of current algorithms. It is able to recognize the moving direction of bus automatically. Moreover, it’s able to solve the problems of reporting failure when bus turn around randomly or positioning data is invalid.(3) The USB driver based on non-operating system is designed and realized for 3G Communication device. It’s depend on the USB host library provided by ST company in 2010, which greatly improves the communication speed between the information issuing terminals and the remote control center. It also reduces the original hardware consumption of the operating system.(4) A management system for the data transmission between the information issuing terminals and the remote control center is designed and realized. The data transmission management references the data transfer mode of USB subsystem in Linux. It adopts the queue strategy of data structure, therefore greatly enhances the stability and data throughput of the system.