Signorile, Giovanna ; Sesia, Ilaria ; Tavella, Patrizia ; Fiasca, Franco ; Defraigne, Pascale ; Galleani, Laurenzo

Talk presented at European Navigation Conference on 2018-05-15

Abstract: In the frame of the Horizon 2020 project DEMETRA (DEMonstrator of EGNSS services based on Time Reference Architecture) funded by the European Union, 9 different time dissemination services based on or alternative to the European GNSS have been designed and experimented. One of them was aimed to test a time integrity service to the GNSS users, to improve user timing accuracy as well as positioning. The DEMETRA Time Integrity Service has been built as a first step of a Galileo time integrity system. The developed service monitors the status of Galileo satellite clocks, detecting in real time possible anomalies and generating automatic alerts in case the satellite is considered unusable. This kind of service will be very useful for users like industrial and scientists interested in timekeeping, but also space qualified clocks manufactures, the European Space Agency (ESA), the European GNSS Agency (GSA), and the European Geostationary Navigation Overlay Service (EGNOS). The Service has been tested in using Galileo public clock data retrieved from the Multi GNSS Experiment of the International GNSS Service (IGS). The service is currently still online and the integrity products available on the DEMETRA web page, accessible to the registered users. The first results will be presented in this paper as well as a comparison against the Galileo NAGU to assess possible improvements at user level, in addition to the information provided by the system itself. Moreover our results have been used to build a statistics on the anomalies that occurred on the Galileo satellite clocks.

Funding: H2020 DEMETRA/H2020 DEMETRA/H2020 DEMETRA