Software Of GPS/DR Integrated Vehicle Navigation System And Algorithm

Nowadays the development of navigation system for land vehicles is just in theascendant. It has been widely used in many fields such as physical distribution andintelligent transportation system. The GPS/DR system is one of the preferable projectsin the integrated vehicle navigation system. On one hand, the system can overcomethe disadvantages of just using GPS, for example, GPS cannot position the locationaccurately when it has been sheltered by other objects. On the other hand, it cancombine the advantages of GPS and DR and so improve the precision of positioningand reliability.Firstly, the thesis researches the application of software engineering in thesoftware design of the GPS/DR system. Considering that most microprocessors havewidely adopted interrupt by hardware, the reason of hardware's interrupt influence tosoftware development has been analyzed. According to the above reason, the softwaremodel for general purpose which describes the interrupt by hardware has beenbrought forward. The model gives attention to data safety and response time at thesame time. The reliability of GPS/DR software has been improved by the applicationof the above interrupt model. Ward & Mellor software development method has beenused to design GPS/DR software system and the algorithm has been carried outefficiently by the method.Secondly, the thesis introduces the multiwavelet theory to the filtering of GPSsignal, details the preprocess and threshold in the application of multiwavelet. Theexperiments show that the precision of positioning is improved. DR navigationhardware project is designed by using MEMS accelerometer and piezo gyro. In orderto deduce the hardware complexity, the method to compensate the gyro tilt errordirectly by utilizing accelerometer has been introduced. The Kalman filter modelapplying to the above hardware project is created and the adaptive Kalman filteralgorithm is also designed. Simulations demonstrate the validity of the algorithm.The algorithm of the integrated vehicle navigation system determines thepositioning accuracy and the software is the guarantee of the system's precision andreliability. The thesis investigates the software and algorithm of GPS/DR by using thetheories of wavelet, optimal state estimation and software engineering, which foundsthe experiment systems and theoretical base for the coming research.