Journal of Geodesy

, Volume 86, Issue 11, pp 991–1003 | Cite as

Zero-difference GPS ambiguity resolution at CNES–CLS IGS Analysis Center

  • Sylvain LoyerEmail author
  • Félix Perosanz
  • Flavien Mercier
  • Hugues Capdeville
  • Jean-Charles Marty
Original Article


CNES (Centre National d’Etudes Spatiales) and CLS (Collecte Localisation Satellites) became an International GNSS Service (IGS) Analysis Center (AC) the 20th of May 2010. Since 2009, we are using the integer ambiguity fixing at the zero-difference level strategy in our software package (GINS/Dynamo) as an alternative to classical differential approaches. This method played a key role among all the improvements in the GPS processing we made during this period. This paper provides to the users the theoretical background, the strategies and the models used to compute the products (GPS orbits and clocks, weekly station coordinate estimates and Earth orientation parameters) that are submitted weekly to the IGS. The practical realization of the two-step, ambiguity-fixing scheme (wide-lane and narrow-lane) is described in detail. The ambiguity fixing improved our orbit overlaps from 6 to 3 cm WRMS in the tangential and normal directions. Since 2008, our products have been also regularly compared to the IGS final solutions by the IGS Analysis Center Coordinator. The joint effects of ambiguity fixing and dynamical model changes (satellite solar radiation pressure and albedo force) improved the consistency with IGS orbits from 35 to 18 mm 3D-WRMS. Our innovative strategy also gives additional powerful properties to the GPS satellite phase clock solutions. Single receiver (zero-difference) ambiguity resolution becomes possible. An overview of the applications is given.


GPS Ambiguity resolution Zero difference IGS analysis center Precise point positioning 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Altamimi Z, Collilieux C, Métivier L (2011) ITRF2008: an improved solution of the international terrestrial reference frame. J Geod 85: 457–473. doi: 10.1007/s00190-011-0444-4 CrossRefGoogle Scholar
  2. Bar-Sever YE, Kroger PM, Borjesson JA (1998) Estimating horizontal gradients of tropospheric path delay with a single GPS receiver. J Geophys Res 103(B3): 5019–5035. doi: 10.1029/97JB03534 CrossRefGoogle Scholar
  3. Bertiger W, Desai SD, Haines B, Harvey N, Moore AW (2010) Single receiver phase ambiguity resolution with GPS data. J Geod 84(5): 327–337CrossRefGoogle Scholar
  4. Boehm J, Niell A, Tregoning P, Schuh H (2006) The global mapping function (GMF): a new empirical mapping function based on numerical weather model data. Geophys Res Lett 33(L07304). doi: 10.1029/2005GL025546
  5. Cerri L, Berthias JP, Bertiger WI, Haines BJ, Lemoine FG, Mercier F, Ries JC, Willis P, Ziebart M (2010) Precision orbit determination standards for the Jason series of altimeter mission. Mar Geod 33(S1): 379–418. doi: 10.1080/01490419.2010.488966 CrossRefGoogle Scholar
  6. Chen G, Herring TA (1997) Effects of atmospheric azimuthal asymmetry on the analysis of space geodetic data. J Geophys Res 102(B9): 20489–20502. doi: 10.1029/97JB01739 CrossRefGoogle Scholar
  7. Collins P (2008) Isolating and estimating undifferenced GPS integer ambiguities. In: Proceedings of the 2008 National technical meeting of the Institute of Navigation, San Diego, USA, 28–30 January, pp 720–732Google Scholar
  8. Dach R, Brockmann E, Schaer S, Beutler G, Meindl M, Prange L, Bock H, Jäggi A, Ostini L (2009) GNSS processing at CODE: status report. J Geod 83(3–4): 353–365. doi: 10.1007/s00190-008-0281-2 CrossRefGoogle Scholar
  9. Delporte J, Mercier F, Laurichesse D, Galy O (2008) GPS carrier-phase time transfer using single-difference integer ambiguity resolution. Int J Navig and Obs. doi: 10.1155/2008/273785
  10. Dow JM, Neilan RE, Gendt G (2009) The international GNSS service in a changing landscape of global navigation satellite systems. J Geod 83(3–4): 191–198CrossRefGoogle Scholar
  11. Fliegel H, Gallini T (1996) Solar force modelling of block IIR global positioning system satellites. J Spacecr Rockets 33(6): 863–866CrossRefGoogle Scholar
  12. Foerste C, Schmidt R, Stubenvoll R, Flechtner F, Meyer U, Koënig R, Neumayer H, Biancale R, Lemoine JM, Bruinsma S, Loyer S, Barthelmes F, Esselborn S (2008) The GeoForschungsZentrum Potsdam/Groupe de Recherche de Geodesie Spatiale satellite-only and combined gravity field models: EIGEN-GL04S1 and EIGEN-GL04C. J Geod 82(6): 331–346. doi: 10.1007/s00190-007-0183-8 CrossRefGoogle Scholar
  13. Fu LL, Christensen EJ, Yamarone CA, Lefbvre M, Menard Y, Dorrer M, Escudier P (1994) TOPEX/Poseidon mission overview. J Geophys Res 99(C12): 24369–24381CrossRefGoogle Scholar
  14. Gambis D (2004) Monitoring Earth orientation at the IERS using space-geodetic observations. State-of-the-art and prospective. J Geod 78(4–5): 295–303. doi: 10.1007/s00190-004-0394-1 CrossRefGoogle Scholar
  15. Geng J, Meng X, Dodson AH, Teferle F (2010) Integer ambiguity resolution in precise point positioning: method comparison. J Geod 84: 569–581CrossRefGoogle Scholar
  16. Griffith J, Ray JR (2009) On the precision and accuracy of IGS orbits. J Geod 83(3–4): 277–287. doi: 10.1007/s00190-008-0237-6 CrossRefGoogle Scholar
  17. Kouba J (2008) A simplified yaw-attitude model for eclipsing GPS satellites. GPS Solutions 13: 1–12. doi: 10.1007/s10291-008-0092-1 CrossRefGoogle Scholar
  18. Kouba J (2009) A guide to using international GNSS service (IGS) products. Accessed 10 Jan 2011
  19. Laurichesse D, Mercier F (2007) Integer ambiguity resolution on undifferenced GPS phase measurements and its application to PPP. ION GNSS 2007 20th international technical meeting of the satellite division, 25–28 Sept 2007, Fort Worth, TX, pp 839–848Google Scholar
  20. Laurichesse D, Mercier F, Berthias JP, Broca P, Cerri L (2009) Integer ambiguity resolution on undifferenced GPS phase measurements and its application to PPP and satellite precise orbit determination. Navig J Inst Navig 56(2):135-149. ISSN:00281522Google Scholar
  21. Lemoine JM, Bruinsma S, Loyer S, Biancale R, Marty JC, Perosanz F, Balmino G (2007) Temporal gravity field models from GRACE data. Adv Space Res 39(10): 1620–1629. doi: 10.1016/j.asr.2007.03.062 CrossRefGoogle Scholar
  22. Lescarmontier L, Legresy B, Coleman R, Perosanz F, Mayet C, Testut L (2012) Vibrations of the Mertz glacier ice tongue. J Glaciol. doi: 10.3189/2012JoG11J089
  23. Lyard F, Lefevre F, Letellier T, Francis O (2006) Modeling the global ocean tides: insights from FES2004. Ocean Dyn. doi: 10.1007/s10236-006-0086-x
  24. Marty JC (ed) (2009) Documentation algorithmique du programme GINS, Version 5 juillet 2009 (in French).
  25. McCarthy DD, Petit G (2004) IERS Conventions 2003. IERS Technical Note 32, Verlag des Bundesamts für Kartographie und Geodäsie Frankfurt am MainGoogle Scholar
  26. Melbourne W (1985) The case for ranging in GPS based geodetic system. In: Goad C (ed) Proceedings of 1st international symposium on precise positioning with the global positioning system. U.S. Department of Commerce, Rockville, Maryland, pp 373–386Google Scholar
  27. Noll CE (2010) The crustal dynamics data information system: a resource to support scientific analysis using space geodesy. Adv Space 45(12): 1421–1440CrossRefGoogle Scholar
  28. Perosanz F, Marty JC, Balmino G (1997) Dynamic orbit determination and gravity field model improvement from GPS. DORIS and laser measurements on TOPEX/Poseidon satellite. J Geod 71: 160–170CrossRefGoogle Scholar
  29. Petit G, Harmegnies A, Mercier F, Perosanz F, Loyer S (2011) The time stability of PPP links for TAI. In: Proceedings of joint conference FCS and EFTF 2011. doi: 10.1109/FCS.2011.5977299
  30. Petrie EJ, Hernández-Pajares M, Spalla P, Moore P, King MA (2010) A review of higher order ionospheric refraction effects on dual frequency GPS. Surv Geophys 32(3): 197–253CrossRefGoogle Scholar
  31. Rebischung P, Garayt B (2012) Recent results from the IGS terrestrial frame combinations. In: Marne-La-Vallée, Altamimi Z, Collilieux X (eds) IAG Symp REFAG2010 (in press)Google Scholar
  32. Reigber C, Balmino G, Schwintzer P, Biancale R, Bode A, Lemoine JM, Koenig R, Loyer S, Neumayer H, Marty JC, Barthelmes F, Perosanz F, Zhu SY (2002) A high quality global gravity field model from CHAMP GPS tracking data and accelerometry (EIGEN-1S). Geophys Res Lett 29(14): 1692. doi: 10.1029/2002GL015064 CrossRefGoogle Scholar
  33. Rodriguez-Solano CJ, Hugentobler U, Steigenberger P, Lutz S (2011) Impact of Earth radiation pressure on GPS position estimates. J Geod. doi: 10.1007/s00190-011-0517-4
  34. Schmid R, Steigenberger R, Gendt G, Ge M, Rothacher M (2007) Generation of a consistent absolute phase center correction model for GPS receiver and satellite antennas. J Geod 81(12): 781–798. doi: 10.1007/s00190-007-0148-y CrossRefGoogle Scholar
  35. Standish E. (1998) JPL planetary and lunar ephemerides DE405/ LE405. Interoffice Memorandum IOM 312.F-98-048. Jet Propulsion Laboratory, PasadenaGoogle Scholar
  36. Tregoning P, Van Dam T (2005) Atmospheric pressure loading corrections applied to GPS data at the observation level. Geophys Res Lett 32(L22310). doi: 10.1029/2005GL024104
  37. Wübbena G (1985) Software developments for geodetic positioning with GPS using TI-4100 code and carrier measurements. In: Goad C (ed) Proceedings of 1st international symposium on precise positioning with the global positioning system.. U.S. Department of Commerce, Rockville, Maryland, pp 403–412Google Scholar

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Sylvain Loyer
    • 1
    Email author
  • Félix Perosanz
    • 2
  • Flavien Mercier
    • 2
  • Hugues Capdeville
    • 1
  • Jean-Charles Marty
    • 2
  1. 1.Collecte Localisation SatellitesRamonville Saint AgneFrance
  2. 2.Centre National d’Etudes SpatialesToulouseFrance

Personalised recommendations