Application of Kohonen maps to the GPS Stochastic Tomography of the Ionosphere

  • M. Hernández-Pajares
  • J. M. Juan
  • J. Sanz
Conference paper
Part of the Studies in Classification, Data Analysis, and Knowledge Organization book series (STUDIES CLASS)


The adaptative classification of the rays received from a constellation of geodetic satellites (GPS) by a set of ground receivers is performed using neural networks. This strategy allows to improve the reliability of reconstructing the Ionospheric electron density from GPS data. As an example, we present the evolution of the radially integrated electron density (Total Electron Content, TEC) during the day 18th October 1995, coinciding with an important geomagnetic storm. Also the problems in the vertical reconstruction of the electron density are discussed, including the data coming from one Low Earth Orbiter GPS receiver: the GPS/MET. Finally is proposed as main conclusion a new strategy to estimate the ionospheric electron distribution, using GPS data, at different scales —the 2-D distribution (TEC) at Global scale and the 3-D distribution (Electron density) at Regional scale—.


Global Position System Total Electron Content Geomagnetic Storm Global Position System Data Global Position System Receiver 
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

© Springer Japan 1998

Authors and Affiliations

  • M. Hernández-Pajares
    • 1
  • J. M. Juan
    • 1
  • J. Sanz
    • 1
  1. 1.Research Group of Astronomy and Space GeodesyUniversitat Politècnica de CatalunyaBarcelonaSpain

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