GPS Solutions

, Volume 13, Issue 2, pp 83–95 | Cite as

Total electron content processing from GPS observations to facilitate ionospheric modeling

  • Angeline G. BurrellEmail author
  • Nelson A. Bonito
  • Charles S. Carrano
Original Article


With the increasing global distribution of high rate dual-frequency global positioning system (GPS) receivers, the production of a real-time atmospheric constituent definition, total electron content (TEC), has become a beneficial contributor to the modeling applications used in the assessment of GPS position accuracy and the composition of the ionosphere, plasmasphere, and troposphere. Historically, TEC measurements have been obtained through post processing techniques to produce the quality of data necessary for modeling applications with rigorous error estimate requirements. These procedures necessitated the collection of large volumes of data to address the various abnormalities in the computation of TEC associated with the use of greater data quality controls and source selection while real-time modeling environments must rely on autonomous controls and filtration techniques to prevent the production of erroneous model results. In this paper we present methods for processing TEC in real time, which utilize several procedures including the application of an ionospheric model to automatically perform quality control on the TEC output and the computational techniques used to address receiver multipath, faulty receiver observations, cycle-slips, segmented processing, and receiver calibrations. The resulting TEC measurements are provided with rigorous error estimates validated using the vertical TEC from the Jason satellite mission.


GPS observations Ionosphere Algorithms TEC processing Total electron content Real-time processing Ionosphere Validation 



Global positioning system


Total electron content


Crustal dynamics data information system


Receiver independent exchange


Center for Orbit Determination in Europe


Ionospheric penetration point


Ultra-high frequency


Parameterized ionospheric model


Union of radio science


Interquartile range



The authors are grateful to all colleagues of the Communication/Navigation Outage Forecasting System team and the Air Force Research Laboratory for providing valuable discussions and suggestions. We thank Dr. Laila S. Jeong for encouraging the implementation of this research and Dr. Brian Wilson of the Jet Propulsion Laboratory for providing the Jason TEC.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Angeline G. Burrell
    • 1
    Email author
  • Nelson A. Bonito
    • 1
  • Charles S. Carrano
    • 1
  1. 1.AER Inc.LexingtonUSA

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