Methodology for the experiment of GPS system for train positioning [Metodologia per la sperimentazione di un sistema GPS per la localizzazione del treno]

This paper analyses the application of satellite technologies to the railway sector, where such technologies are playing an increasingly important role for signaling, communications, diagnostics and security. The aim of this work has been to examine and evaluate GPS satellite observations in combination with data from a RTK receiver obtained from the projects 3InSat and ERSAV, a trial and validation test site has been placed in Sardinia, it is based on the combination of the ERTMS / ETCS and the satellite tracking technology, integrated with TLC (i.e. GSM-3G, Tetra, Satellite) systems using the IP protocol. These projects have been recently set up by Ansaldo STS and Rete Ferroviaria Italiana (RFI) and the University of Catania in order to create a trial and validation site in Sardinia - that is located along the railway track 'Cagliari-San Gavino' - for assessing the consequences of satellite-based technologies on the railway infrastructures and systems. The acceptability of the work has been supported by the fact that the average precision position per train trip was always lower than 3 meters in line with railway standards.