A new approach for pure kinematical and reduced-kinematical determination of LEO orbit based on GNSS observations

Abstract

The geometrical point-wise satellite positions of a Low Earth Orbiter (LEO) equipped with a Global Navigation Satellite System (GNSS) receiver can be derived by GNSS analysis techniques based on hl-SST (high-low Satellite to Satellite Tracking) observations. In the geometrically determined LEO orbit, there is no connection between subsequent positions, and consequently, no information about the velocity and the acceleration or in general kinematical information of the satellite is available. If the kinematical parameters which consistently connects positions, velocities and accelerations are determined by a best fitting process based on the observations, we perform a pure Kinematical Precise Orbit Determination (KPOD). In addition, the proposed approach has a capability to use certain dynamical constraints based on the dynamical force function model. In this case, we introduce a Reduced-Kinematical Precise Orbit Determination (RKPOD) of a specific level depending on the strength of the "dynamical constraints". The various possibilities and the corresponding results of CHAMP orbits based on GNSS observations are presented. © Springer-Verlag Berlin Heidelberg 2012.