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Journal of Geodesy

, Volume 87, Issue 4, pp 351–360 | Cite as

Fast error analysis of continuous GNSS observations with missing data

  • M. S. Bos
  • R. M. S. Fernandes
  • S. D. P. Williams
  • L. Bastos
Original Article

Abstract

One of the most widely used method for the time-series analysis of continuous Global Navigation Satellite System (GNSS) observations is Maximum Likelihood Estimation (MLE) which in most implementations requires \(\mathcal{O }(n^3)\) operations for \(n\) observations. Previous research by the authors has shown that this amount of operations can be reduced to \(\mathcal{O }(n^2)\) for observations without missing data. In the current research we present a reformulation of the equations that preserves this low amount of operations, even in the common situation of having some missing data.Our reformulation assumes that the noise is stationary to ensure a Toeplitz covariance matrix. However, most GNSS time-series exhibit power-law noise which is weakly non-stationary. To overcome this problem, we present a Toeplitz covariance matrix that provides an approximation for power-law noise that is accurate for most GNSS time-series.Numerical results are given for a set of synthetic data and a set of International GNSS Service (IGS) stations, demonstrating a reduction in computation time of a factor of 10–100 compared to the standard MLE method, depending on the length of the time-series and the amount of missing data.

Keywords

GNSS Error Power-law 

Notes

Acknowledgments

The authors would like to thank the assistant editor Jeff Freymueller and three anonymous reviewers for their thorough and constructive review of our manuscript. This work was funded by national funds through FCT in the scope of the Project PesTC/ Mar/LA0015/2011.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • M. S. Bos
    • 1
  • R. M. S. Fernandes
    • 2
    • 3
  • S. D. P. Williams
    • 4
  • L. Bastos
    • 1
    • 5
  1. 1.CIIMAR/CIMAR, University of PortoPortoPortugal
  2. 2.University of Beira Interior, IDLCovilhãPortugal
  3. 3.Delft Earth-Oriented Space Research (DEOS), DUTDelftThe Netherlands
  4. 4.National Oceanography Centre, LiverpoolLiverpoolUK
  5. 5.Faculty of Science, DGAOTUniversity of PortoPortoPortugal

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