The Navigation Support Office is leading the Galileo Geodetic Service Provider (GGSP), which is responsible for the realisation and maintenance of a Galileo Terrestrial Reference Frame (GTRF). The GTRF is one of the key components contributing to the system performance of Europe's Global Navigation Satellite System Galileo. It is compatible with the latest International Terrestrial Reference Frame (ITRF) within a precision level of 3 cm (2 sigma). To achieve this goal, a Galileo Geodetic Service Provider (GGSP) has been defined by the Galileo project already in the early stages of the Galileo programme.

A prototype system, funded within the sixth framework program of the European Union, has been established from 2005 to 2009 by a consortium of geodetic institutions:  




  • European Space Operations Centre (ESA/ESOC), Darmstadt, Germany

  • Helmholtz-Zentrum Potsdam, Deutsches GeoForschungsZentrum (GFZ), Potsdam, Germany

  • Astronomisches Institut der Universität Bern (AIUB), Berne, Switzerland

  • Bundesamt für Kartographie und Geodäsie (BKG), Frankfurt/Main, Germany

  • Institut National de l'Information Géographique et Forestière (IGN), Paris, France

The prototype system was incorporated in 2009 the Galileo Time and Geodetic Validation Facility (TGVF) and renamed to Orbit Validation Facility (OVF). In addition to the GTRF the OVF is delivering a wide variety of monitoring products, including precise orbit, clock, station coordinate, Earth orientation parameter, atmosphere and bias estimates, as rapid, with a delay of 12 hours, and most accurate, final products with a delay of 14 days. Only with such a complete and consistent set of high precision products the GGSP can truly fulfil its prime task of providing a reference frame to the various Galileo user communities. In addition, these high precision products are extremely valuable for the validation of the operational products generated by Galileo Ground Mission Segment (GMS). The OVF is fully operational and is meeting the FOC availability and accuracy requirements.


Zandbergen, R., E. Schoenemann, T. Springer, J. Martin, W. Enderle, M. Uhlemann, M. Fritsche, R. Dach, L. Prange, E. Orliac, Z. Altamimi, J. Chenal, W. Soehne, J. Dostal, A. Rülke, F. Gonzalez, R. Swinden, S. Binda (2015): The Galileo Terrestrial Reference Frame and the Galileo Orbit Validation Facility. 5th Galileo Science Colloquium 2015, October 27-29, Braunschweig, Germany,  Download .

Gendt, G.; Altamimi, Z.; Dach, R.; Söhne, W.; Springer, T. (2011): GGSP: Realisation and maintenance of the Galileo Terrestrial Reference Frame. Advances in Space Research, 47, 2, 174-185.