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A Study of the Diurnal in the Transatlantic TWSTFT Difference



Victor S. Zhang, Thomas E. Parker


The daily variation (diurnal) in the two-way satellite time and frequency transfer (TWSTFT) difference is one of the most significant instabilities of the TWSTFT technique. The diurnal comes from the daily delay change of the TWSTFT signal paths. In recent years, there is a persistent diurnal, at 1 ns to 2 ns level, in the transatlantic and the Europe-to-Europe TWSTFT links. In this paper, we study the diurnal in the transatlantic TWSTFT differences. We will show a small part of diurnal is due to the path non-reciprocity between a earth station and a satellite; the diurnal can come from multiple TWSTFT signals transmitted at the same time; TWSTFT using different satellites and frequencies results in different diurnal levels; and environment effect of the earth stations and the satellite transponders also contribute to the daily delay variation of the TWSFTF difference.
Proceedings Title
Proceedings of the 2013 Asia-Pacific Radio Science Conference
Conference Dates
September 3-7, 2013
Conference Location
Conference Title
2013 Asia-Pacific Radio Science COnference


Time and Frequency Transfer, Two-Way Satellite Time and Frequency Transfer


Zhang, V. and Parker, T. (2013), A Study of the Diurnal in the Transatlantic TWSTFT Difference, Proceedings of the 2013 Asia-Pacific Radio Science Conference, Taipei, (Accessed June 21, 2024)


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Created September 7, 2013, Updated February 19, 2017