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Navigation



                An European system Galileo is under construction and operational together with

                Navstar. Several large nations also have satellite navigation systems. Information

                from  Navstar  and  Galileo  is  used  in  our  GNSS  (Global  Navigation  Satellite

                System).

                In  current  peacetime,  the  accuracy  is  high.  Within  a  few  meters  in  all  three

                dimensions.



                9.10.3.1    Structure of the system


                The system consists of three segments:

                   - Space segment

                   - Ground segment
                   - User segment













                The space segment

                The space segment consists of satellites.


                The operational system operates with 24 satellites divided into 6 orbits with 4

                satellites in each orbit. In addition, there are spare satellites. The satellites are in

                orbit approximately 20,200 km above the Earth's surface.

                The  satellites  each  receive  their  positions  updated  from  the  Master  Control

                Station, which receives information from monitoring antennas located around

                the globe.




                Each  satellite  constantly  transmits  a  Navigation  Message,  which  contains

                information about the individual satellite and the constellation of satellites. This

                is done in the form of an almanac and an ephemeris.



              Flyveteori PPL(A)(UL)/LAPL             Henning Andersen, Midtjysk Flyveskole© marts 2026        898
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