GGTO: Stability and Impact on Multi-constellation Positioning

Ciro Gioia, Daniele Borio

Abstract:	Global Navigation Satellite Systems (GNSSs) usually operate using independent time scales. For this reason, the determination of inter-system time offsets is required to enable multi-constellation navigation. The Galileo to GPS Time Offset (GGTO) defines the difference between the Galileo and GPS time scales. In this paper, three different approaches for the determination of the GGTO are considered and their performance is evaluated using measurements from four multiconstellation receivers. The performance is evaluated using live GPS and Galileo data. From the analysis, it emerges that the GGTO is very stable and that different receivers provides different estimates of the GGTO which are usually biased with respect to the one computed using the broadcast parameters. The estimation of the GGTO significantly improves position performance which is further enhanced when constraints are imposed on the GGTO time variations.
Published in:	Proceedings of the 28th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2015) September 14 - 18, 2015 Tampa Convention Center Tampa, Florida
Pages:	245 - 249
Cite this article:	Gioia, Ciro, Borio, Daniele, "GGTO: Stability and Impact on Multi-constellation Positioning," Proceedings of the 28th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2015), Tampa, Florida, September 2015, pp. 245-249.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In