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CCTF Working Group on Two-Way Satellite Time and Frequency Transfer (CCTF-WGTWSTFT)

Terms of reference

  • to perform coordination activities related to TWSTFT between participating and prospective institutes,
  • to act as a point of contact for BIPM on TWSTFT matters,
  • to organize the operation of TWSTFT links to support the production of TAI,
  • to perform calibration campaigns to reduce the time link uncertainties between participating institutes,
  • to observe and review the needs for remote frequency and time comparisons of frequency standards and atomic time scales,
  • to establish and maintain dedicated TWSTFT links to support remote clock comparisons,
  • to identify future needs of remote clock comparisons,
  • to undertake research for the improvement of TWSTFT and
  • to follow and assess other techniques, including GNSS, optical fibers, optical satellite links which could be used for remote (optical) clock comparisons, and
  • together with BIPM, to foster the spread of information on technical achievements by suitable means, e.g. via BIPM webpage.
September 2012


  • Mr Victor Zhang  (NIST)


  • Dr Frédéric Meynadier  (BIPM)


  • The members of the working group are representatives and especially experts of the participating institutes as well as representatives of prospective participating institutes. Representatives of institutes interested in this field are encouraged to follow the activities as observers.

Contact persons:

  • Dr Joseph Achkar (LNE-SYRTE)
  • Mr Russel Bumgarner (USNO)
  • Dr Clément Courde (OCA)
  • Dr Albin Czubla (GUM)
  • Mr Erik Dierikx (VSL)
  • Dr Héctor Esteban (ROA)
  • Dr Miho Fujieda (NICT)
  • Dr James Hanssen (USNO)
  • Dr Yi-Jiun Huang (TL)
  • Dr Ryuichi Ichikawa (NICT)
  • Dr Shinn-Yan Lin (TL)
  • Mr François Meyer (LNE-LTFB)
  • Mr Andrey Naumov (VNIIFTRI)
  • Dr Jerzy Nawrocki (AOS)
  • Dr Pawel Nogas (AOS)
  • Dr Thomas E. Parker (NIST)
  • Dr Dirk Piester (PTB)
  • Dr Carlos Pires (IPQ)
  • Mr Carsten Rieck (RISE)
  • Dr Christian Schlunegger (METAS)
  • Dr Ilaria Sesia (INRIM)
  • Dr Tomonari Suzuyama (NMIJ/AIST)
  • Mr Peter Whibberley (NPL)
  • Dr Wenjun Wu (NTSC)
  • Dr Zhiqiang Yang (NIM)
  • Mr Sung Hoon Yang (KRISS)
  • Dr Shengkang Zhang (BIRM)
  • Prof. Aimin Zhang (NIM)

  CCTF: Upcoming meetings
11–12 March 2021: Second session of the 22nd meeting of the CCTF (online)
18–19 March 2021: Second session of the 22nd meeting of the CCTF (online)
27 June to 1 July 2022: 23rd meeting of the CCTF and related meetings

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BIPM Workshop on Advanced Time & Frequency Transfer Techniques 2011