Near-earth satellite orbit determination and its applications

The technique for determining a satellite's orbit from range and other tracking data is described. Such techniques are required both during a mission, as a means of supporting various classes of users, and before a mission, in the form of simulation. The full sophistication of the techniques is requried when satellites are used as probes of geodetic and geodynamical phenomena. Parameters that can be derived from precise orbit determination include polar motion, tectonic-plate motion, solid-Earth tides and Earth-rotation rates.