18 March 2020
First time: The time scales of LNE-SYRTE(OP) and Physikalisch-Technische Bundesanstalt (PTB) were linked by Two-Way Satellite Time and Frequency Transfer, using Software-Defined Radio receivers (SDR).
The new method is using SDR receivers that replaces part of the satellite reception system with high-speed digitization and software data processing. This solution significantly improves the time stability of the time scales comparison, down to 60 ps for 1-day averaging time.
These new receivers have been installed in several timing laboratories in Asia, Europe and the United States. After a pilot study which lasted three years [1], and after having demonstrated the accuracy of the link and its reliability, the satellite link between OP and PTB based on an SDR solution is used for the first time in UTC computation (Circular T 386 of Bureau International des Poids et Mesures (BIPM)).
Time difference UTC(OP) – UTC(PTB), in nanosecond, as measured by regular TWSTFT link (green cross) and improved with Software-Defined Radio (SDR) receiver (blue dot). Source: BIPM, March 2020.
For more information:
On the method
Additional Scientific Paper in Metrologia
Contact Researcher: Joseph Achkar, joseph.achkar@observatoiredeparis.psl.eu
Footnotes
[1] initiated by the CCTF Working Group on TWSTFT