Skip to main content
SpringerLink
Log in

Time and Frequency Metrology in the Context of Relativistic Geodesy

  • Chapter
  • First Online:
Relativistic Geodesy

Part of the book series: Fundamental Theories of Physics ((FTPH,volume 196))

Abstract

A status report is given on current practice and trends in time and frequency metrology. Emphasis is laid on such fields of activity that are of interest in the context of relativistic geodesy. In consequence, several topics of a priori general relevance will not be dealt with. Clocks and the means of comparing their reading are equally important in practically all applications and thus dealt with in this contribution. The performance of commercial atomic clocks did not change significantly during the last 20 years. Progress is noted in the direction of miniaturization, leading to the wide-spread use of chip-scale atomic clocks. On the other hand, research institutes invested considerably into the perfection of their instrumentation. Cold-atom caesium fountain clocks realize the SI-second with a relative uncertainty of close to \(1\times 10^{-16}\), and with a relative frequency instability of the same magnitude after averaging over a few days only. Optical frequency standards are getting closer to being useful in practice: outstanding accuracy combined with improved technological readiness can be noted. So one necessary ingredient for relativistic geodesy has become available. Satellite-based time and frequency comparison is here still somewhat behind: Time transfer with ns-accuracy and frequency transfer with \(1\times 10^{-15}\) per day relative instability have become routine. Better performance requires new signal structures and processing schemes, some appear on the horizon.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Log in via an institution
Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 109.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Hardcover Book
USD 139.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    Note: Although this is a review article, my intention was not to provide an exhaustive list of references, but rather to limit myself to text books and previous review articles of other authors with few exceptions.

  2. 2.

    In order to understand the word “leap”: Only very few fountain clocks achieve an instability as shown, see discussion in Sect. 3.2.

  3. 3.

    For improved hold-over capability, some models include a Rb frequency standard (see Sect. 3.1) that is steered with a few hours time constant.

  4. 4.

    As an aside, I remember well that my start as PhD student at PTB in 1983 coincided with the installation of the first receiver of this kind in the PTB time-unit laboratory, a single-channel GPS receiver for time transfer provided by the then National Bureau of Standards (now NIST). This receiver is now at display in the Deutsche Uhrenmuseum (German clock museum), Furtwangen, Black Forest.

  5. 5.

    Source of data: BIPM ftp server at ftp://ftp2.bipm.org/pub/tai/timelinks/lkc/, data in monthly files, Read Me file provided.

References

  1. A. Bjerhammar, On relativistic geodesy. Bull. Geod. 59, 207 (1985)

    Article  Google Scholar 

  2. H. Denker et al., Geodetic methods to determine the relativistic redshift at the level of \(10^{-18}\) in the context of international timescales - a review and practical results. J. Geod. 92, 487 (2018) to be published

    Google Scholar 

  3. Standard definitions of Physical Quantities for Fundamental Frequency and Time Metrology, IEEE-Std 1189–1988 (IEEE, 1988)

    Google Scholar 

  4. W.J. Riley, Handbook of Frequency Stability Analysis, NIST Special Publication, vol. 1065 (NIST, 2008)

    Google Scholar 

  5. Joint Committee for Guides in Metrology, Evaluation of Measurement Data - Guide to the Expression of Uncertainty in Measurement. JCGM 100:2008 (2008)

    Google Scholar 

  6. J. Vanier, C. Audoin, The Quantum Physics of Atomic Frequency Standards (Adam Hilger, Bristol, 1989)

    Google Scholar 

  7. J. Vanier, C. Tomescu, The Quantum Physics of Atomic Frequency Standards - Recent Developments (CRC Press, Taylor & Francis Group, Boca Raton, 2016)

    Book  Google Scholar 

  8. C. Audoin, B. Guinot, The Measurement of Time (Cambridge University Press, Cambridge, 2001)

    Google Scholar 

  9. E.F. Arias, A. Bauch, Metrology of time and frequency, in Handbook of Metrology ed. by M. Gläser, M. Kochsiek (WILEY-VCH Verlag, Weinheim, 2010), p. 315

    Google Scholar 

  10. R. Lutwak et al., The MAC - a miniature atomic clock. Proceedings 2005 International Frequency Control Symposium and Exhibition (2005), p. 752

    Google Scholar 

  11. P. Forman, Atomichron®: the atomic clock from concept to commercial product. Proc. IEEE 73, 1181 (1985)

    Article  ADS  Google Scholar 

  12. L.S. Cutler, Fifty years of commercial caesium clocks. Metrologia 42, S90 (2005)

    Article  ADS  Google Scholar 

  13. A. Bauch, The PTB primary clocks CS1 and CS2. Metrologia 42, S43 (2005)

    Article  ADS  Google Scholar 

  14. N.F. Ramsey, Experiments with separated oscillatory fields and hydrogen masers (Nobel Lecture). Rev. Mod. Phys. 62, 541 (1990)

    Article  ADS  Google Scholar 

  15. R. Piriz et al., The time validation facility (TVF): an all-new key element of the Galileo operational phase. Proceedings of the Joint IEEE International Frequency Control Symposium and the European Frequency and Time Forum, Denver (2015), p. 320

    Google Scholar 

  16. H.J. Metcalf, P. van der Straten, Laser-Cooling and Trapping (Springer, New York, 1999)

    Book  Google Scholar 

  17. R. Wynands, S. Weyers, Atomic fountain clocks. Metrologia 42, S64 (2005)

    Article  ADS  Google Scholar 

  18. V. Gerginov et al., Uncertainty evaluation of the caesium fountain clock PTB-CSF2. Metrologia 47, 65 (2010)

    Article  ADS  Google Scholar 

  19. B. Lipphard, V. Gerginov, S. Weyers, Optical stabilization of a microwave oscillator for fountain clock interrogation. IEEE Trans. Ultrason. Ferroelectr. Freq. Control. 99, 99 (2016)

    Google Scholar 

  20. G. Petit, G. Panfilo, Comparison of frequency standards used for TAI. IEEE Trans. Intrumentation Meas. 62, 1550 (2013)

    Article  Google Scholar 

  21. N.K. Pavlis, M.A. Weiss, The relativistic redshift with \(3\times 10^{-17}\) uncertainty at NIST, Boulder, Colorado, USA. Metrologia 40, 66 (2003)

    Article  ADS  Google Scholar 

  22. S. Peil et al., Evaluation of long term performance of continuously running atomic fountains. Metrologia 51, 263 (2014)

    Article  ADS  Google Scholar 

  23. BIPM, Le Système international d’unités (The International System of Units), 8th edition. BIPM, Pavillon de Breteuil, F-92312 Sèvres Cedex, France, 2006, 2014 update)

    Google Scholar 

  24. F. Riehle, Frequency Standards: Basics and Applications (Wiley VCH, Weinheim, 2006)

    Google Scholar 

  25. T.W. Hänsch, Passion for precision (Nobel lecture). Rev. Mod. Phys. 78, 1297 (2006)

    Article  ADS  Google Scholar 

  26. A.D. Ludlow et al., Optical atomic clocks. Rev. Mod. Phys. 87, 637 (2015)

    Article  ADS  Google Scholar 

  27. H. Dehmelt, Coherent spectroscopy on single atomic system at rest in free space. J. Phys. (Paris) 42, C8–299 (1981)

    Article  Google Scholar 

  28. H. Katori, Spectroscopy of Strontium atoms in the Lamb-Dicke confinement, in Proceedings of the 6th Symposium on Frequency Standards and Metrology (2001). ((St. Andrews, Scotland), the proceedings were published by World Scientific, Singapore, in 2002, p. 323)

    Google Scholar 

  29. N. Huntemann et al., Single-ion atomic clock with \(3\times 10^{-18}\) systematic uncertainty. Phys. Rev. Lett. 116, 063001 (2016)

    Article  ADS  Google Scholar 

  30. S.B. Koller et al., Transportable optical lattice clock with \(7\times 10^{-17}\) uncertainty. Phys. Rev. Lett. 118, 073601 (2017)

    Article  ADS  Google Scholar 

  31. B. Guinot, E.F. Arias, Atomic time-keeping from 1955 to the present. Metrologia 42, S20 (2005)

    Article  Google Scholar 

  32. BIPM Time Department. Circular T. BIPM, http://www.bipm.org/en/bipm-services/timescales/time-ftp/Circular-T.html

  33. P. Gill, F. Riehle, On secondary representations of the second, in Proceeding of the 20th European Frequency and Time Forum (2006), p. 282

    Google Scholar 

  34. G. Petit et al., UTCr: a rapid realization of UTC. Metrologia 51, 33 (2014)

    Article  ADS  Google Scholar 

  35. A. Bauch et al., Generation of UTC(PTB) as a fountain-clock based time scale. Metrologia 49, 180 (2012)

    Article  ADS  Google Scholar 

  36. C. Lisdat et al., A clock network for geodesy and fundamental science. Nat. Commun. 7, 12443 (2016)

    Article  ADS  Google Scholar 

  37. Ł. Śliwczyński et al., Fiber-optic time transfer for UTC-traceable synchronization for telecom networks. IEEE Commun. Stand. Mag. 1, 66 (2017)

    Article  Google Scholar 

  38. J. Levine, A review of time and frequency transfer methods. Metrologia 45, S162 (2008)

    Article  ADS  Google Scholar 

  39. ITU Study Group 7, ITU Handbook: Satellite Time and Frequency Transfer and Dissemination (International Telcommunication Union, Geneva, 2010)

    Google Scholar 

  40. E.D. Kaplan, C.J. Hegarty (eds.), Understanding GPS, Principles and Applications, 2nd edn. (Artech, Boston, London, 2006)

    Google Scholar 

  41. RINEX Working Group and RTCM-SC104, RINEX The Receiver Independent Exchange Format Version 3.02. International GNSS Service (2013), https://igscb.jpl.nasa.gov/igscb/data/format/rinex302.pdf

  42. J. Kouba, P. Heroux, Precise point positioning using IGS orbit and clock products. GPS Solut. 5(2), 12 (2002)

    Article  Google Scholar 

  43. P. Defraigne, G. Petit, CGGTTS-Version 2E: an extended standard for GNSS time transfer. Metrologia 52, G1 (2015)

    Article  Google Scholar 

  44. G. Petit et al., \(10^{-16}\) frequency transfer by GPS PPP with integer ambiguity resolution. Metrologia 52, 301 (2015)

    Article  ADS  Google Scholar 

  45. D. Kirchner, Two-way satellite time transfer. Review of Radio Science 1996–1999 (1999), p. 27

    Google Scholar 

  46. A. Bauch, D. Piester, M. Fujieda, W. Lewandowski, Directive for operational use and data handling in two-way satellite time and frequency transfer (TWSTFT). BIPM, Rapport 2011/01, 2011 (2011)

    Google Scholar 

  47. A. Bauch et al., Comparison between frequency standards in Europe and the USA at the \(10^{-15}\) uncertainty level. Metrologia 43, 109 (2006)

    Google Scholar 

  48. L. Cacciapuoti, Chr. Salomon, Space clocks and fundamental tests: the ACES experiment. Eur. Phys. J. Spec. Top. 172, 57 (2009)

    Article  ADS  Google Scholar 

  49. L. Cacciapuoti, Chr. Salomon, Atomic clock ensemble in space. J. Phys. Conf. Ser. 327, 012049 (2011)

    Google Scholar 

  50. E. Peik, A. Bauch, More accurate clocks - What are they needed for? PTB-Mitteilungen 119(2), 16 (2009)

    Google Scholar 

  51. I.H. Stairs, Testing general relativity with pulsar timing. Living Rev. Relativ. (2003), http://relativity.livingreviews.org/open?pubNo=lrr-2003-5&=node5.html

  52. G. Hobbs, Development of a pulsar-based time-scale. Mon. Not. R. Astron. Soc. 427, 2780 (2012)

    Article  ADS  Google Scholar 

  53. R.A. Hulse, The discovery of the binary pulsar (Nobel Lecture). Rev. Mod. Phys. 66, 699 (1994)

    Article  ADS  Google Scholar 

  54. J.H. Taylor, Binary pulsars and relativistic gravity (Nobel Lecture). Rev. Mod. Phys. 66, 711 (1994)

    Article  ADS  Google Scholar 

  55. N. Huntemann et al., Improved limit on a temporal variation of \(m_p/m_e\) from comparisons of \(Yb^{+}\) and Cs atomic clocks. Phys. Rev. Lett. 113, 210802 (2014)

    Article  ADS  Google Scholar 

  56. C. Lisdat, Private communication (2017)

    Google Scholar 

Download references

Acknowledgements

This review paper reports mostly on achievements of colleagues from all over the world. The fruitful collaboration belonged to the pleasures of the author’s business life. Special thanks go to Ekkehard Peik, Dirk Piester and Stefan Weyers of PTB for critical reading of the manuscript.

Author information

Authors and Affiliations

  1. Physikalisch-Technische Bundesanstalt, Bundesallee100, 38116, Braunschweig, Germany

    Andreas Bauch

Authors
  1. Andreas Bauch
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Andreas Bauch .

Editor information

Editors and Affiliations

  1. ZARM, University of Bremen, Bremen, Germany

    Dirk Puetzfeld

  2. ZARM, University of Bremen, Bremen, Germany

    Claus Lämmerzahl

Rights and permissions

Reprints and permissions

Copyright information

© 2019 Springer Nature Switzerland AG

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Bauch, A. (2019). Time and Frequency Metrology in the Context of Relativistic Geodesy. In: Puetzfeld, D., Lämmerzahl, C. (eds) Relativistic Geodesy. Fundamental Theories of Physics, vol 196. Springer, Cham. https://doi.org/10.1007/978-3-030-11500-5_1

Download citation

Publish with us

Policies and ethics

Search

Navigation