Optimal Path Algorithm Based On Real-time Traffic Information And Its Implementation

Intelligent transportation system is the integration of the advanced information technology, data communication technology, electronic control technology and computer processing technology in the whole traffic system. By means of the real-time traffic information collection, transmission, and processing, the system can set up a real-time, accurate and efficient integrated transportation management system, with the aid of various high-tech means and equipment for the coordination and processing of various traffic situations. The intelligent transportation system makes full use of traffic facilities and is able to improve the traffic efficiency and security, ultimately it makes transportation service and management intelligent and gains intensive development of transportation. Vehicle navigation system is an important part in intelligent transportation system, which searches the optimal path in the city road network from source to destination based on the real-time traffic information received from the traffic information center. The optimal path planning technology is the core technology of the vehicle navigation system, and is the foundation to realize the vehicle navigation functions.This thesis first summarizes the concept of intelligent transportation system and its components and introduces the intelligent transportation system research status at home and abroad. Then it summarizes the vehicle navigation system and introduces the concept and form of the vehicle navigation system at home and abroad, as well as the present situation and progress of the research. Then it discusses and analyzes some classical shortest path algorithm principle and its advantages and disadvantages. Based on the Dijkstra algorithm and the actual traffic conditions an improved Dijkstra algorithm is put forward. The algorithm considers the road traffic congestion by making the running time as weights. The traditional Dijkstra algorithm node has not right value, while the algorithm makes the intersection delay time as a node of the right value to take into account of the intersection delay time, The algorithm also considers the actual network in the presence of one way street. These three factors are taken into accounted in the improved Dijkstra algorithm.At last, the thesis builds a simulation platform and develops the route guidance system module, with Windows7as a development platform and Microsoft Visual Studio2005as a development tool. Through the simple simulation, it can be seen that the improved algorithm in this thesis can figure out the optimal path which is close to reality and has great practical value.