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Bulletin géodésique

, Volume 64, Issue 3, pp 283–294 | Cite as

Local geoid computation from gravity using the fast fourier transform technique

  • D. Nagy
  • R. J. Fury
Article

Abstract

Model computations were performed for the study of numerical errors which are interjected into local geoid computations byFFT. The gravity field model was generated through the attractions of granitic prisms derived from actual geology. Changes in sampling interval introduced only0.3 cm variation in geoid heights. Although zero padding alone provided an improvement of more than5 cm in theFFT generated geoid, the combination of spectral windowing (tapering) and padding further reduced numerical errors. For theGPS survey of Franklin County, Ohio, the parameters selected as a result of model computations, allow large reduction in local data requirements while still retaining the centimeter accuracy when tapering and padding is applied.

Keywords

Global Position System Gravity Anomaly Numerical Error Padding Geoid Height 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Bureau Central de L’Association Internationale de Géodésie 1990

Authors and Affiliations

  • D. Nagy
    • 1
  • R. J. Fury
    • 2
  1. 1.Geophysics DivisionGeological Survey of CanadaOttawaCanada
  2. 2.National Geodetic SurveyNOS/NOAARockvilleUSA

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