Recommendation 4 of the 20th CCTF (2015)

On the Common Generic GNSS Time Transfer Standard (CGGTTS)

The Consultative Committee for Time and Frequency (CCTF),

considering that

• the CGGTTS format and standard is used by time laboratories to transfer the time of their clocks to the computation of UTC,
• the software ‘R2CGGTTS’ is commonly used by UTC laboratories to generate CGGTTS data,
• the deployment of the Galileo, QZSS and BeiDou constellations is in progress and should be completed in the coming years,
• several receiver manufacturers already provide Global Navigation Satellite Systems (GNSS) observations from the different constellations;

noting that

• an extension of the CGGTTS format has been defined under the name V2E so as to include the time transfer results from the GPS, GLONASS, BeiDou, Galileo and QZSS satellites,
• the complete description of the V2E standard has been made publicly available in Metrologia 2015 52 G1;

recommends that

• the CCTF WG on GNSS Time Transfer (WGGNSS) interacts with manufacturers of timing receivers to request that they upgrade their firmware so as to provide version V2E of the CGGTTS,
• the time laboratories provide CGGTTS files to the BIPM in the V2E format,
• the software ‘R2CGGTTS’ be upgraded to generate the version V2E.

DOI : 10.59161/CCTF2015REC4E