Satellite Orbit and Ephemeris Determination using Inter Satellite Links

Orbit ComputationInter Satellite Links4002000Orbit Error [m]-200-400-600-800-1000-1200-1400RadialAlong TrackCross Track19:12:30.000 01:52:30.000 08:32:30.000UTC [hours:minutes:seconds]Figure 4-4 Orbit Error of MEO neglecting Lunar AttractionObviously the LEO satellite is less affected by third body attractions than satellites in MEO (or GEO and IGSO)orbits. It is a general tendency that the direct tidal effect increases with orbit height. This can easily be verifiedby setting the satellites radius in Eq. 4.2-46 to zero which causes the third body attraction to vanish.The following table show the orbit errors due to neglecting lunar attraction for predictionperiods of one day and six hours.Page 48R. Wolf