Construction of GPS-based LEO orbits referenced to the “instantaneous” Earth’s center of mass, through the adjustment of a parametric correction in the IGS GPS satellite clock solutions

Alexandre Couhert (CNES, France)

CoAuthors

Flavien Mercier (CNES, France); Nicolas Delong (CNES, France)

Event: 2017 Ocean Surface Topography Science Team Meeting

Session: Precision Orbit Determination

Presentation type: Type Oral

The International GNSS Service (IGS) solutions for the GPS constellation are aligned to the ITRF origin. This strategy is not sufficient to model correctly the LEO GPS measurements, because the geocenter motion is not taken into account for the ground station positions in these solutions. As a consequence, the clock products are slightly biased in order to represent directly a convenient ITRF positioning for the users. All Analysis Centers (AC) follow this recommendation to align their solution to conform to the ITRF origin.
In order to be consistent with the dynamic motion of a LEO satellite, and also to be consistent with the other measurement systems where the geocenter motion is modelled (SLR and DORIS, annual part in the current GDR-E standards), it is necessary to take into account or to mitigate the miscentering effect of the constellation solution.
In this paper, we use a parametric model representing the reference network translations, and this model is adjusted in the Jason-2 LEO satellite orbit determination.
 

Oral presentation show times:

RoomStart DateEnd Date
Symphony II Tue, Oct 24 2017,11:00 Tue, Oct 24 2017,11:15
Alexandre Couhert
CNES
France
alexandre.couhert@cnes.fr