| As a crucial part of Intelligent Transportation System (ITS), Route Guidance System (RGS) is an effective way of solving the transportation-related problems such as driving-induced stress, congestion and air pollution. Being one of the core techs of RGS, Shortest Path Algorithm (SPA) is the basis of a correct and effective route guidance function.In this thesis, the systemic method of shortest path planning in a Vehicle Autonomous Navigation System (VANS) is studied, including: real-time adaptive SPA based on dynamic discrete-time network, method of dealing with the limitation of real traffic network, door-to-door path planning, method of organizing large-scale traffic network data, path planning through different maps, protocol of traffic data transmission between information center and on-vehicle terminal for a dynamic route guidance system. Based on the continuous property of the traffic flow, a dynamic discrete-time network is established, the "FIFO" character of the network is analyzed, and an effective dynamic adaptive routing algorithm is proposed based on the idea of A* algorithm.Adaptations are made in algorithm according to traffic limitations. The problem of obtaining shortest path including repeated nodes and roads is solved. Also the door-to-door path planning problem is solved by modifying road network temporarily.An optimal format for storing large-scale traffic network data is established, also is a management method for large-scale traffic network data. The problem of path planning through different regions of the whole country is solved by a method of matching results of path planning.A testing platform of dynamic route guidance system is established, also is the protocol between information center and on-vehicle terminal. Implemented the complete algorithm considering all the aspects above and integrated it into a commercial GPS VANS product.The simulation and real road experiments showed that the algorithm is practical and reliable.
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