How does mobile GPS work?
Since the GPS, finding the way is no longer a problem! Just open the map, you can easily know what you're in position. But how GPS works?
Earth has 24 GPS satellites, divided into six groups, synchronous orbit satellite is not static, from west to east at a speed of 8000 miles per hour flight, they would circle the earth twice a day. On board of each satellite atomic clock, and reports
Mobile phone GPS receivers will capture time and flight time from the satellite. Signal in when, where, GPS receivers will be calculated in which position you on earth.
When you drive high-speed mobile, it will also calculate speed and compass heading, but GPS speed is usually a few miles an hour slower than car drivers. Data will appear in the navigation system, satellite signals from the earth's atmosphere from 40-600 miles through the ionosphere, creates a delay. Therefore, GPS is usually applied calibration system.
In general, we need three GPS signals to determine (also called "triangle law") the location of the receiver, and then use the fourth signal to calculate the height.
In addition, the more the number of satellite receiver, positioning of the higher quality. If the atomic clock is not accurate, or inaccurate information into other, GPS can be revised.
At present, the GPS technology based on ground reference stations was used to correct the precision. This technique can be SA signal positioning within 15 meters, about 2 the length of the car. In the best case, its precision can reach 10 centimeters, even the accuracy has been very good.
Ok, the GPS to help us understand the position and the surrounding traffic conditions, is life provides great convenience for us.