The influence of different satellite altitude angles on GPS/GLONASS/BDS/Galileo fusion positioning

This paper studied the offects of different satellites elevation on GPS/GLONASS/BDS/Galileo (G+R+B+E) fusion positioning and corresponding model was established. Using global navigation satellite system (GNSS) data provided by MGEX(Multi-GNSS Experiment), the theoretical analysis and experiments showed that, combination of G+R+B+E increased the number of satellite used for positioning, and could ensure a relative large number of satellites and a good space geometric distribution structure. Satellites elevation had little effect on positioning result when the satellites of combined system reached a certain number. External error accuracy of G+R+B+E combination in 3D direction was improved when satellites elevation was larger than 30°.