Geometrical and Kinematical Precise Orbit Determination of GOCE

Abstract

The geometrical point-wise Low Earth Orbiters (LEO) positions can be derived by Global Navigation Satellite System (GNSS) analysis techniques. The different precise point positioning techniques based on GNSS observations will be designated as Geometrical Precise Orbit Determination (GPOD) methods. In the geometrical determined LEO orbit, there is no connection between subsequent absolute positions, and consequently, no information about the velocity or even the acceleration (or in general kinematical information) of the satellite is available. To describe the time dependency of the motion of a satellite, it is necessary to provide a properly constructed function which consistently connects positions, velocities and accelerations. In this investigation, a new approach is presented based on approximation parameters, which have also a clearly defined relation to the dynamical model of the satellite's motion. If the kinematical parameters are determined by a best fitting process based on the GNSS observations, then we perform a pure Kinematical Precise Orbit Determination (KPOD). The geometrical and kinematical precise orbit of Gravity field and steady-state Ocean Circulation Explorer (GOCE) based on real high-low Satellite to Satellite Tracking (hl-SST) GNSS observations will be presented.