Research Of GPS Positioning System Based On MapX

This paper uses the latest GPS and GIS technology, proposes a secondary development model for GIS based on MapX components. By realizing data communication using short message service in GPRS module, we can apply embedded system to remote monitoring system, and further more, provide methods to location, tracking, navigation, and so on. Also, we provide implementation method of this system. The design goal is to realize accurate location of every front terminal which have GPS receiver. The location data is reliable transferred using GPRS wireless communication system, meanwhile, our system also provides a interface for users to do some interactive operation. The system in this paper is a sub-project of ITS, which can relieve traffic congestion and can improve the efficient use of road infrastructure, so this system has important practical significance.Firstly, this paper proposes research background of this system, analysis current development and clear practical significance and goal of this system, and also describes system integrity from software and hardware structure of system design. We design hardware structure of this system in detail, choose ARM7TDMI as our embedded micro-processor, and design hardware of power supply, reset circuit, storage, GPRS module and GPS module. For software design, we divide our system into GPS location module and GPRS communication module. We discuss the migration of uc/os-II in detail, and cut kernel and file system. This paper does further research on technology and theory of system development, especially describes basic system theory and research results of GPS location technology, GPRS communication technology and MapX component technology.Secondly, this paper designs and realizes GPS location processing system, it is the mobile part of GPS system. The location processing system is made up of GPS location module, data processing module and GPRS communication module. The main purpose of this system is to collect analysis, filter and test GPS navigation data. Also this paper gives some algorithms used in GPS processing module, including GPS navigation data processing. WGS-84 coordinate transformation, map matching, and so on. Especially, we design GPS navigation data and NMEA-0183 statement output protocol, data frame format, coding format, data verification and so on.Thirdly, this paper completes design of communication sub-system using GPRS module. We realize wireless communication transfer based on GSM/GPRS module, and solves technology bottleneck using short message service in GPRS. We design AT instruction to control mobile equipment for short message communication, and realize synchronic design of GPRS thread and GPS thread. Our system makes a communication bridge between front location system and PC using wireless communication system. Front ARM system can send operation command and receive location information through GPRS, and transfer data and command to PC through serial port. We use MSComm component to realize serial port communication.Finally, this paper completes the development of kernel part of GPS location system, we call it GIS. We developed digital maps used in our system. MapX component was embedded into VC++ application to build and realize basic digital map display system. We realized map loading function, built user map tools, designed and completed database for information management and query, improved database function module, completed bundle design of map data. Finally, GIS can load GPS location points to maps, and update layer display after certain time.The design and implementation of the system mainly takes the use of the ARM7TDMI microprocessor, GPS receiver, GPRS wireless communication module. Access database. MSComm Maplnfo serial communication control and development tools, using MFC application under VC++environment completes the GPS positioning system model based on MapX components, realizes the functions of the designed navigation and positioning, wireless communications, and basic geographic information service and so on. Through a database bound method, dynamic layer in the GIS shows anchor, based on verified MapX component of the feasibility of GPS positioning. The system has built a digital map information database and dynamic loading. Discuss the development process of the positioning system about the key technical points and the difficulties encountered in hardware and software design approach for the research and laid the theoretical and technical basis deeply. The system exists errors within the standard error of the experimental data and data shows that the system has a good positioning and monitoring functions.