Design Of Vehicle Terminal Based On BDS/GPS Dual Mode Positioning System

With the sharp rise in car ownership, more and more problems of road traffic arebreaking out. Intelligent transportation systems (ITS) have been developed to solvethese problems, effectively. Under ITS, transport resources can be reasonablyexplored and allocated through the analysis of data from vehicles and roadways. Inorder to facilitate the data collection, upload and user response, vehicle terminals,which can provide support for the fast and accurate upload of vehicle location andvehicle status information to the service platform of ITS, and ensure correct responseaccording to strategies provided by the service platform, was developed.The BeiDou Navigation Satellite System (BDS) is a Chinese satellite navigationsystem. The application of BDS in the vehicle terminals is of great significance inpromoting the development of the BeiDou satellite navigation industry chain. Atpresent, BDS is still under construction, however, the combination of BDS and GPScan provide more accurate and reliable location-based services.The development of vehicle terminals is to collect data for ITS, and there are twomajor tasks of achieving this goal. First, the collection of vehicle location informationbased on the dual-mode satellite positioning of BDS-GPS need to be fulfilled.Followed by the need to achieve is on the collection of vehicle CAN bus information.On the basis of two acquisition tasks, the vehicle terminal can establish a TCP connectto platform via GPRS wireless network and upload the real-time data collected. Basedon the above design goal, this paper includes the following:1) Introduces the development status of intelligent transportation systems andBeidou satellite navigation system. Through the practical issues raised the purpose ofthe car terminal development and has carried on the demand analysis. According tothe vehicle terminal core function of demand and the status of the satellite navigationsystem, the design of the core function was determined that the design of the corefunction (LBS) using Beidou/GPS dual-mode satellite positioning. 2) To build a hardware platform based on the ARM11, and positioning module,the CAN information collection module and wireless communication moduleintegrated into a circuit board. Positioning module and the wireless communicationmodule via the serial port to communicate with CPU, and CAN bus controller via theSPI interface to connect and control.3) Based on the ARM11embedded hardware platform, Windows Embedded CE6.0operating system was transplanted. Windows Embedded CE6.0operating systemis a real-time multi-tasking operating system, using of the operating system will bringgreat convenience to the subsequent development.4) Based on Windows Embedded CE6.0operating system, there are severalachievements of the applications. They are parsing and processing the NMEA-0183standard statement outputted by Beidou/GPS dual-mode the positioning module, thecollection of CAN-bus data, and establishing a TCP connection with platform viaGPRS wireless network and uploading the real-time data collected.