The Car Navigation Service System Of The Design And Implementation

Intelligent transportation systems (ITS) is the future trend of the transportation system, Dynamic traffic information service is an effective means to alleviate the pressure on road traffic. Traditional static traffic information is contained road network information and building facilities information. The dynamic traffic information refers to the real-time traffic information such as traffic flow and traffic incident. Consider the real-time traffic information on the basis of information on the static road network, can provide an optimal driving route planning, reduce travel time, improve the operating efficiency of the road network.Unlike the traditional vehicle navigation systems, dynamic navigation system uses a client-server (C/S) mode of service, the navigation terminal and service center. The service center is the key to dynamic information service, primarily responsible for receive, process and release dynamic traffic information. The navigation terminal use the information which is released by the service center to display the dynamic traffic information on the map, finish path planning and road-induced.Dynamic information transmission using wireless network transmission technology, low delay, high reliability. Navigation map data is stored using a hierarchical structure of the block, the entire map data grid in the form of regional management, significantly increase the speed of reading the map data, and more suitable for electronic map online incremental update technology. In order to preserve the dynamic traffic information, design navigation map database. Add the effective time field in point, line, area map elements and build real-time traffic information table.The design of the navigation system can obtain real-time traffic information periodically driving position near, the information will be drawn on the screen of the navigation terminal. Conducting path planning, navigation system takes to calculate the dynamic traffic information around the section of road, get the better optimal path than the path which is based on static data.During the road-induced, when the dynamic traffic information changes the system can renew the path planning, guiding the vehicle driving on the new path. For vehicle navigation systems, By functional tests can prove dynamic traffic information service system is a very effective solution.