Journal of Geodesy

, Volume 85, Issue 12, pp 941–948 | Cite as

GPS radio occultation measurements on ionospheric electron density from low Earth orbit

Original Article


Since the proof-of-concept GPS/Meteorology (GPS/MET) experiment successfully demonstrated active limb sounding of the Earth’s neutral atmosphere and ionosphere via GPS radio occultation (RO) from low Earth orbit, the developments of electron density (ne) retrieval techniques and powerful processing systems have made a significant progress in recent years. In this study, the researches of ne profiling from space-based GPS RO observations are briefly reviewed. Applying to the Formosat-3/Constellation Observing System for Meteorology, Ionosphere and Climate (FS3/COSMIC) data, we also present a compensatory Abel inversion technique including the effects of large-scale horizontal gradients and/or inhomogeneous ionospheric ne obtained from an improved near real-time phenomenological model of the TaiWan Ionospheric Model. The results were evaluated by the ionosonde foF2 and foE data and showed improvements of rms foF2 difference from 29.2 to 16.5% in relative percentage and rms foE difference from 54.2 to 32.7% over the standard Abel inversion.


Ionospheric electron density Radio occultation Abel inversion 


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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.Center for Space and Remote Sensing ResearchNational Central UniversityChung-LiTaiwan
  2. 2.Graduate Institute of Space ScienceNational Central UniversityChung-LiTaiwan
  3. 3.Earth and Environmental SciencesNational Chung Cheng UniversityChia-YiTaiwan
  4. 4.Academia SinicaTaipeiTaiwan

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