Potential of VLBI observations to satellites for precise orbit determination

Besides the natural extra-galactic radio sources, observing an artificial Earth-orbiting radio source with the Very Long Baseline Interferometry (VLBI) permits to extend the geodetic and geodynamic applications of this highly accurate interferometric technique. Furthermore, combining aforementioned observations provides a promising method to determine the satellite orbit and delivers the new type of observations such as group delay and delay rate which might be employed to validate the orbit independent of other space geodetic techniques.

In this research, the potential of the interferometric satellite tracking for the Precise Orbit Determination (POD) has been explored based on simulated observations for different scenarios with various VLBI networks, satellite orbits (eccentric low Earth orbits or circular medium Earth orbits) and error sources. POD of the Earth-orbiting satellites is studied on the basis of daily VLBI sessions where satellite observations are scheduled together with the quasar observation for regionally or globally distributed legacy as well as next generation VLBI station networks. In order to simulate VLBI to satellite observations, the influence of the most prominent random error sources in VLBI as well as mismodelling of different force models acting on the satellite are utilized. This study indicates that POD is feasible with VLBI observations and the accuracy mainly depends on the observation geometry.