A direct comparison between two independently calibrated time transfer techniques: T2L2 and GPS Common-Views

8th Symposium on Frequency Standards and Metrology 2015

Rovera, G.D.^1 ; Abgrall, M.^1 ; Courde, C.^2 ; Exertier, P.^2 ; Fridelance, P.^3 ; Guillemot, Ph^4 ; Laas-Bourez, M.^2 ; Martin, N.^2 ; Samain, E.^2 ; Sherwood, R.^5 ; Torre, J.-M.^2 ; Uhrich, P.^1

LNE-SYRTE, Observatoire de Paris, PSL Research University, CNRS, Sorbonne Universités, UPMC Univ. Paris 06, 61 avenue de l'Observatoire, Paris

75014, France^1

Geoazur, CNRS, Observatoire de la Côte d'Azur, UNS, Sophia-Antipolis

06560, France^2

Phusipus Intégration, Saint Vallier, France^3

CNES French Space Agency, Paris, France^4

NERC Space Geodesy Facility Herstmonceux, United Kingdom^5

关键词: Combined uncertainty;    Gps common views;    Optical satellites;    Reference points;    Satellite time;    Standard deviation;    Time transfer;    Time transfer techniques;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/723/1/012037/pdf
DOI  :  10.1088/1742-6596/723/1/012037

来源: IOP

【 摘 要 】

We present a direct comparison between two satellite time transfer techniques on independently calibrated links: Time Transfer by Laser Link (T2L2) and Common-Views (CV) of satellites from the Global Positioning System (GPS) constellation. The GPS CV and T2L2 links between three European laboratories where independently calibrated against the same reference point of the local timescales. For all the links the mean values of the differences between GPS CV and T2L2 are equal or below 240 ps, with standard deviations below 500 ps, mostly due to GPS CV. Almost all deviations from 0 ns are within the combined uncertainty estimates. Despite the weak number of common points obtained, due to the fact that T2L2 is weather dependent, these results are providing an unprecedented sub-ns consistency between two independently calibrated microwave and optical satellite time transfer techniques.