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Volume 52 Supplement 10

Special Issue: Application of GPS and other space geodetic techniques to Earth Sciences (1)

Development and assessment of a medium-range real-time kinematic GPS algorithm using an ionospheric information filter


The key requirement of centimeter-level real-time kinematic (RTK) positioning using the Global Positioning System (GPS) relies on the ability to fast and accurately determine the ambiguities of carrier-phase observations to their inherent integer values. In addition, the identification must be completed on the fly since the remote receiver is constantly in motion. The Kalman filter-based algorithm described in this paper uses an ionospheric information filter to perform on-the-fly phase ambiguity resolution for high precision RTK applications. Experiments based on 16 independent test baselines ranging from 10–50 km in length indicate that the algorithm can reliably achieve centimeter-level positioning accuracy, provided that a small enough threshold value for ambiguity identification is pre-defined and that sufficient geometry change in the GPS constellation is observed. Experimental results also show that the convergence (initialization) time for ambiguity resolution is linearly proportional to instantaneous baseline length, and the slope of the regression line increases with tighter ambiguity identification criteria.


  1. Ashkenazi, V., C. J. Hill, W. Y. Ochieng, and J. Nagle, Wide-area differential GPS: a performance study, Navigation, 40, 297–319, 1993.

    Article  Google Scholar 

  2. Bertiger, W. I., Y. E. Bar-Sever, B. J. Haines, B. A. Iijima, S. M. Lichten, U. J. Lindqwister, A. J. Mannucci, R. J. Muellerschoen, T. N. Munson, A. W. Moore, L. J. Romans, B. D. Wilson, S. C. Wu, T. P. Yunck, G. Piesinger, and M. Whitehead, A real-time wide area differential GPS system, Navigation, 44, 433–447, 1998.

    Article  Google Scholar 

  3. Beutler, G., M. Rothacher, S. Schaer, T. Springer, J. Kouba, and R. E. Neilan, The international GPS service (IGS): an interdisciplinary service in support of earth sciences, Adv. Space Res., 23, 631–653, 1999.

    Article  Google Scholar 

  4. Dong, D. and Y. Bock, Global positioning system network analysis with phase ambiguity resolution applied to crustal deformation studies in California, J. Geophys. Res., 94, 3949–3966, 1989.

    Article  Google Scholar 

  5. Gelb, A., Applied Optimal Estimation, 370 pp., MIT Press, Cambridge, MA, U.S.A., 1979.

    Google Scholar 

  6. Goad, C. C. and M. Yang, A new approach to precision airborne GPS positioning for photogrammetry, Photogrammetric Engineering and Remote Sensing, 63, 1067–1077, 1997.

    Google Scholar 

  7. Han, S., Carrier Phase-based Long-range GPS Kinematic Positioning, Ph.D. Thesis, 185 pp., School of Geomatic Engineering, The University of New South Wales, Sydney, Australia, 1997.

    Google Scholar 

  8. Hopfield, H. S., Two-quartic tropospheric refractivity profile for correcting satellite data, J. Geophy. Res., 74, 4487–4499, 1969.

    Article  Google Scholar 

  9. Huang, Y. N., K. Cheng, and S. W. Chen, On the equatorial anomaly of the ionospheric total electron content near the northern anomaly crest region, J. Geophys. Res., 94, 13515–13525, 1989.

    Article  Google Scholar 

  10. Klobuchar, J. A., Ionospheric effect on GPS, GPS World, 2, 48–51, 1991.

    Google Scholar 

  11. Mohamed, A. H. and K. P. Schwarz, A simple and economical algorithm for GPS ambiguity resolution on the fly using a whitening filter, Navigation, 45, 221–231, 1999.

    Article  Google Scholar 

  12. Neilan, R. E., J. F. Zumberge, G. Beulter, J. Kouba, The international GPS service: a global resource for GPS applications and research, Proc. ION GPS-97, 883–889, 1997.

  13. Raquet, J. and G. Lachapelle, Development and testing of a kinematic carrier-phase ambiguity resolution method using a reference receiver network, Navigation, 46, 283–295, 2000.

    Article  Google Scholar 

  14. Saastamoinen, I. I., Contribution to the theory of atmospheric refraction, Bulletin Geodesique, 107, 13–34, 1973.

    Article  Google Scholar 

  15. Seeber, G., Satellite Geodesy, 531 pp., Walter de Gruyter, Berlin, Germany, 1993.

    Google Scholar 

  16. Solheim, F. S., Use of pointed water vapor radiometer observations to improve vertical GPS surveying accuracy, Ph.D. Dissertation, Department of Physics, University of Colorado, Boulder, CO, U.S.A., 1993.

    Google Scholar 

  17. Teunissen, P. J. G., The invertible GPS ambiguity transformations, Manuscripta Geodaetica, 20, 489–497, 1995.

    Google Scholar 

  18. Teunissen, P. J. G., The geometry-free GPS ambiguity search space with a weighted ionosphere, J. Geod., 71, 370–383, 1997.

    Article  Google Scholar 

  19. Yang, M. and C. F. Lo, Real-time kinematic GPS positioning for centimeter level ocean surface monitoring, Proc. Natl. Sci. Counc. ROC(A), 24, 79–85, 2000.

    Google Scholar 

  20. Yang, M., C. C. Goad, and B. Schaffrin, Real-time on-the-fly ambiguity resolution over short baselines in the presence of anti-spoofing, Proc. 7th International Technical Meeting of the Satellite Division of the ION, 519–525, 1994.

  21. Wang, J., Stochastic modeling for real-time kinematic GPS/GLONASS positioning, Navigation, 46, 297–305, 2000.

    Article  Google Scholar 

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Correspondence to Ming Yang.

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Yang, M., Tang, CH. & Yu, TT. Development and assessment of a medium-range real-time kinematic GPS algorithm using an ionospheric information filter. Earth Planet Sp 52, 783–788 (2000).

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  • Global Position System
  • Ambiguity Resolution
  • Integer Ambiguity
  • Phase Ambiguity
  • Differential Global Position System