Characterization of Short-Term GNSS Satellite Clock Stability

Erin R. Griggs, E. Robert Kursinski, Dennis M. Akos

Abstract:	Global Navigation Satellite System (GNSS) clock stability is analyzed using a modified Allan deviation (MAD) for time intervals of 1 ? ? ? 200 seconds. Active hydrogen masers are used as the receiver reference to effectively isolate the satellite clock contribution to the variance of the carrier phase from the various GNSS signals. Satellite clock stability for four different GNSS constellations are presented, highlighting the similarities and differences between the constellations as well as satellite blocks and clock types. The rubidium frequency standards (RFS) onboard the Global Positioning System (GPS) Block IIF, BeiDou, and Galileo satellites show improved short-term stability results in comparison to previous GPS blocks and GLONASS. The cesium frequency standards (CFS) on-board the GLONASS satellites are shown to have significantly higher MAD values in comparison to the other GNSS constellations, indicating the need for supplemental clock corrections for high-rate applications wishing to utilize the GLONASS signals. Sub-second Allan analysis is limited by the internal processing algorithms of the commercial receiver used in this study, but achievable with high enough signal-to-noise and a better understood software receiver.
Published in:	Proceedings of the 46th Annual Precise Time and Time Interval Systems and Applications Meeting December 1 - 4, 2014 Seaport Boston Hotel Boston, Massachusetts
Pages:	170 - 175
Cite this article:	Griggs, Erin R., Kursinski, E. Robert, Akos, Dennis M., "Characterization of Short-Term GNSS Satellite Clock Stability," Proceedings of the 46th Annual Precise Time and Time Interval Systems and Applications Meeting, Boston, Massachusetts, December 2014, pp. 170-175.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In