GPS Solutions

, Volume 9, Issue 2, pp 88–95 | Cite as

Ionospheric GPS radio occultation measurements on board CHAMP

Original Article


The GPS radio occultation technique is a rather simple and inexpensive tool for getting information about the global characteristics of the vertical electron density distribution. No other ionospheric sounding technique (bottomside/topside vertical sounding, incoherent scatter) unifies vertical profiling through the entire ionosphere with global coverage. The paper addresses retrieval methods and algorithms applied for the generation of operational products including their limitations in accuracy and spatial resolution. Preliminary results of ionospheric radio occultation (IRO) measurements carried out onboard the German CHAMP satellite are reported. The achieved accuracy of the retrieved electron density profiles (EDPs) is estimated in particular by comparing the IRO results with independent vertical sounding data from European stations. It is concluded that CHAMP-IRO measurements have the potential to establish global data sets of EDPs, contribute to ionospheric research, develop and improve global ionospheric models and to provide operational space weather information.


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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR)Institut für Kommunikation und Navigation (IKN)NeustrelitzGermany

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