Research On Application Of GPS/DR/MM Integrated System To Vehicle Navigation

In recent years, with the development of the micro-electronics technique, the price of GPS receiver have been greatly falling , and as a result of the United States closing SA to stop limiting the public position accuracy of GPS , the GPS positioning accuracy have improved greatly in public field. All this consumedly promote the development of GPS in public field, and especially in the vehicle navigation field , GPS shows its superiorly navigation performance. The GPS applied to the vehicle navigation have already become one of the biggest industry in GPS application field. The vehicle loaded the navigation system run mostly in the downtown. However, the GPS' work would suffer seriously the influence of the particular environment in the downtown, and can't so much as complete the positioning. So this paper study mainly the design of the GPS/DR integrated vehicular navigation system in order to realizing continuous and Real-time navigation in the downtown. At the same time, for providing the result of positioning that have no error nearly for drivers, this paper study the method of map matching.This paper analyze the development of the vehicle positioning and navigation system, and the system configuration and request of autonomic navigation system and central navigation system. The GPS positioning modes that can be introduced in the vehicle navigation system are analyzed, the navigation algorithm and accuracy of GPS vehicle navigation system are studied .and it is proved by simulation. The main errors that influent the positioning accuracy are analyzed, and the method of lowering the effects of multipath is discussed. The basic principle of Dead Reckonning system is analyzed, and the principle and errors of a few adoptab'e DR sensors are introduced .For realizing continuous and Real-time navigation in the downtown, A federated Kalman filter mechanization to realize the optimal synthesis of GPS/DR integrated navigation system is designed first, and its algorithm is presented. Moreover, an adaptive federated Kalman filter mechanization and its algorithm is proposed for GPS/DR integrated vehicle navigation system. The theoretical analysis and simulation results all show that the positioning accuracy and redundancy of the GPS/DR integrated navigation system can be greatly improved by using the adaptive federated Kalman filter.For providing the result of positioning that have no error nearly for drivers, this paper analyze the coding of digital map used to vehicle navigation , and studied two method of map matching: the method of map matching based on probability and the method of map matching based on the coding of digital map and direction information.Finally, simulation software used to study vehicle navigation was designed. Realized simple GIS system, downtown environment simulation, sole GPS positioning simulation, sole DR system simulation , GPS/ DR integrated system simulation .The software has a certain practical value.