Estimation of Uncertainties in Time Error Estimation

Abstract

In navigation satellite systems, it is necessary to determine the difference between the on-board time and the reference time for each satellite. This often can be estimated in real time by filtering time measurements collected over a ground station network and has to be extrapolated when the satellite is out of visibility of this network. This analysis has been carried out at the CNES in the GNSS2 and GALILEO context and leads to specifications on adjustment and extrapolation errors of the on-board time. The purpose of this paper is the estimation of the difference between the extrapolation and the real on-board time. After the description of the method, an example is given using real data, and the predicted extrapolation uncertainties are compared to the real extrapolation errors.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1999
Accession Number
ADA497124

Entities

People

  • Francois Vernotte
  • Jerome Delporte
  • Michel Brunet
  • Thierry Tournier

Tags

DTIC Thesaurus Topics

  • Artificial Satellites
  • Data Science
  • Equations
  • Errors
  • Extrapolation
  • Frequency
  • Ground Stations
  • Information Science
  • Interpolation
  • Intervals
  • Navigation Satellites
  • Random Walk
  • Square Roots
  • Standards
  • Statistics
  • Time Intervals
  • Uncertainty

Readers

  • Positioning, Navigation, and Timing (PNT) Technology.
  • Theoretical Analysis.

Technology Areas

  • Space