GLONASS和GPS 区别

GPS_GlonassIQ2010/IQnav GPS/GLONASS Overview

What is GPS ?


A global navigation system that can provide an accurate location and time information anywhere on our near the earth. It is a collection of 31 satellites that orbit the earth at an altitude of 20,000 km. The satellites are placed in 6 different orbits at an inclination of 55and each of them has a 12 hour orbit. At any given time there are at least 6 different satellites which are visible from a certain point on the earth. To get a location fix, the GPS device needs to lock in to 4 of the 6 visible satellites. 4 satellites are needed as there are 4 variables