1. Université de Toulouse; UPS-OMP; IRAP; Toulouse France
2. CNRS; IRAP; Toulouse France
3. CNES, Department of Terrestrial and Planetary Geodesy; Toulouse France
4. Univ. Paris Diderot, Sorbonne Paris Cité, Institut de Physique du Globe de Paris; UMR 7154 CNRS Paris France
5. Faculty of Aerospace Engineering, TU Delft; Delft Netherlands
6. EOST; Strasbourg France