What is GPS?
The Global Positioning System consists out of 24 satellites placed in 6 different orbital planes.
Figure 1.1: GPS configuration
The 6 orbital planes are inclinated at 55 degrees (with respect to the equatorial plane).
At a height of 20.000 km, the GPS satellites need 12 hours to orbit around the Earth.
GPS was created in 1973 by the U.S. Department of Defense (DoD).
GPS is maintained by 5 DoD Control Stations. The Master Control Station is suited in Colorado Springs.
Abbildung 1.2: GPS Control Stations
Author: Michael Schulz, GEOSOFT