The Journal of the Astronautical Sciences

, Volume 56, Issue 3, pp 375–399 | Cite as

Estimation of total electron content (TEC) using spaceborne GPS measurements



TerraSAR-X (TSX), a high-resolution interferometric Synthetic Aperture Radar (SAR) mission from DLR (German Aerospace Center, Deutsches Zentrum für Luft-und Raumfahrt), was successfully launched into orbit on June 15, 2007. It includes a dual-frequency GPS receiver called IGOR (Integrated GPS Occultation Receiver), which is a heritage NASA/JPL BlackJack receiver. The software for the TSX IGOR receiver was specially-modified software developed at UT/CSR. This software was upgraded to provide enhanced occultation capabilities. This paper describes total electron content (TEC) estimation using simulation data and onboard GPS data of TerraSAR-X. The simulated GPS data were collected using the IGOR Engineering Model (EM) in the laboratory and the onboard GPS data were collected from the IGOR Flight Model (FM) on TSX. To estimate vertical total electron content (vTEC) for the simulation data, inter-frequency biases (IFB) were estimated using the “carrier to code leveling process.” For the onboard GPS data, IFBs of GPS satellites were retrieved from the navigation message and applied to the measurements.


Mapping Function Total Electron Content Carrier Phase Ionospheric Delay Vertical Total Electron Content 


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Copyright information

© American Astronautical Society, Inc. 2008

Authors and Affiliations

  1. 1.Center for Space ResearchThe University of Texas at AustinUSA
  2. 2.Aerospace Engineering and Engineering Mechanics DepartmentThe Unversity of Texas at AustinUSA

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