BIPM Time Dept database
BIPM Time Department Data Base

Complete documentation and guidelines to contribute to UTC and UTCr is available in following documents :

Prerequisites :

  • Administrative requirements for contribution to UTC
  • Technical requirements for contribution to UTC
  • Laboratory information spreadsheet
  • Technical recommendation for UTC(k)

  • >> General technical guideline <<



    - Atomic clocks :

  • Get clock code here
  • Clock file format

  • - Time transfer :

  • List of recent GNSS receivers contributing to UTC and their manufacturer

  • Global Navigation Satellite System file format (CGGTTS format) :
           GPS only (Version 1 ), GPS+GLONASS (Version 2), all GNSS (Version 2E)
           Download R2CGGTTS software for CGGTTS generation (last updated version 8.1)
  • LZ file format
  • PPP and HD file format
  • TWSTFT file format (ITU-R)
  • CGGTTS and TWSTFT Header examples

  • - PSFS (Primary and Secondray Frequency Standards) :

  • Guideline for reporting primary (PFS) or secondary (SFS) frequency standards data for TAI calibration (January 2022)
  • PSFS data file format (May 2020)

  • - Other :

  • Meteorological data file format (Oct.2018)

  • - CCTF Working Group TAI

  • Relevant information, membership and nomination form ( to be filled by Director of Institute)


  • If you have not found an answer to your question in this documentation, please contact us


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