Study On GPS/DR Integrated Navigation Technology For Vehicle Based On Embedded Linux

On the urban street or in the space between the high buildings, the singal of GPS may be interrupted which will result in GPS's position error. This paper presents an aided Dead Reckoning (DR) system based on low cost magnetorsistive sensor and speedometer sensor. The DR system can cover the shortage of GPS. The GPS/DR integrated navigation system can also increase reliability of system.The paper demonstrates development history of position and navigation system for vehicle, and the situation of position technology for vehicle. The method to realize integrated position is analyzed. Navigation technology and the characteristic of embedded Linux operation system are introduced. A GPS/ DR integrated navigation system for vehicle is designed, in which a 32-bits embedded microchip MC9328MXL is used as CPU. How to design Linux device drivers are also studied.The paper analyses the errors of navigaiton sensors, and presents a corresponding compensation process. The position of vehicle is computed by using the singal of multisensors in the GPS/DR integrated navigation system. Therefore, the multisensors data fusion algorithm must be used to improve the position precision and reliability of the system. It puts forward an adaptive federated Kalman filtering algorithm in which the distributive coefficient of information is decided by HDOP(Horizontal Dilution of Precision). Practical applications have testified that the algorithm which fuses the data collected from the sensors of GPS and DR makes the system have high accuracy positioning function.The paper presents an application of real time and multithread characteristic of embedded Linux. It briefly introduces the method and the program of real time sampling from multi-interface and multitask. Practical applications have testified that real time and multitask characteristic of embedded Linux is suitable for the real-time response, real-time count and multitask of the system, it results in a high performance-price-ratio.