Time:2010-10-22
Automotive navigation system is a global satellite positioning system (GPS) developed on the basis of new technology. Car ownership in the world increases every year, to bring about a serious road traffic congestion and crowded, become a major environmental hazard, but also caused huge economic losses. Build roads, increase the flow capacity, although an important way to solve traffic congestion, but some roads wind developed countries have the world well aware that highway expansion alone to solve the traffic congestion is very limited, and must seek a high science and technology to the solution - Automotive navigation system.
The principles of automotive navigation systems
GPS is a positioning satellite signal can be received through the microprocessor to calculate the exact longitude and latitude where the car and the car speed and direction, and displayed on the display of a device.
How to locate the GPS?
It is through the ground at any point (such as cars) and over the four positioning satellites to calculate the relative distance of the exact location of the car. If we know the distance of a satellite pitch, we can know that the point must be at the center of the sphere to the first satellite, the distance of the sphere radius, if we know the distance from the second satellite of known satellites, we can confirm that point of intersection of two spheres in a circular curve, with the third satellite that we can be before the third sphere and a circular curves intersect at two points, generally the distance through the fourth satellite that we uniquely determine the latitude and longitude of the point.
GPS system was originally in the military needs for combat troops to provide accurate positioning, such as aircraft, ships, etc., to ensure that the initiative campaign. A few years ago began in the civil promotion, mainly used in navigation, mapping, speed, vehicle theft, and scheduling.
In addition to accurate GPS positioning, there are the following functions:
It can directly enter the names, latitude and longitude, the line phone number to retrieve and quickly provide the best route to a destination; a result of road congestion, road construction or the wrong way and other unforeseen circumstances, the best route is not feasible, the search can then provide a new route; order to advance understanding of the driver driving the changes in the road, it can make the voice prompts, such as general road 500 m before the 1,000 meters before the highway road conditions and driver that can be changed direction; vehicle driving in the intersection before crossing the whole real screen can automatically map, specify the name of the intersection, turn after the road name and direction, which is a major automotive navigation capabilities. Can be said that the biggest civilian GPS car navigation market is.
