Journal of Geodesy

, Volume 89, Issue 4, pp 331–345 | Cite as

SHPTS: towards a new method for generating precise global ionospheric TEC map based on spherical harmonic and generalized trigonometric series functions

  • Zishen LiEmail author
  • Yunbin YuanEmail author
  • Ningbo Wang
  • Manuel Hernandez-Pajares
  • Xingliang Huo
Original Article


To take maximum advantage of the increasing Global Navigation Satellite Systems (GNSS) data to improve the accuracy and resolution of global ionospheric TEC map (GIM), an approach, named Spherical Harmonic plus generalized Trigonometric Series functions (SHPTS), is proposed by integrating the spherical harmonic and the generalized trigonometric series functions on global and local scales, respectively. The SHPTS-based GIM from January 1st, 2001 to December 31st, 2011 (about one solar cycle) is validated by the ionospheric TEC from raw global GPS data, the GIM released by the current Ionospheric Associate Analysis Center (IAAC), the TOPEX/Poseidon satellite and the DORIS. The present results show that the SHPTS-based GIM over the area where no real data are available has the same accuracy level (approximately 2–6 TECu) to that released by the current IAAC. However, the ionospheric TEC in the SHPTS-based GIM over the area covered by real data is more accurate (approximately 1.5 TECu) than that of the GIM (approximately 3.0 TECu) released by the current IAAC. The external accuracy of the SHPTS-based GIM validated by the TOPEX/Poseidon and DORIS is approximately 2.5–5.5 and 1.5–4.5 TECu, respectively. In particular, the SHPTS-based GIM is the best or almost the best ranked, along with those of JPL and UPC, when they are compared with TOPEX/Poseidon measurements, and the best (in addition to UPC) when they are validated with DORIS data. With the increase in the number of GNSS satellites and contributing stations, the performance of the SHPTS-based GIM can be further improved. The SHPTS-based GIM routinely calculated using global GPS, GLONASS and BDS data will be found at the website


Global ionospheric TEC map (GIM) GNSS TOPEX/Poseidon DORIS 



We are grateful to the editor-in-chief (Roland Kleesthe), the handling editor (Johannes Böhm) and three anonymous reviewers for their editorial feedback and valuable suggestions. This research was partially funded by the National Basic Research Program of China (No. 2012CB825604), China Natural Science Funds (Nos. 41304034, 41231064, 41104012), Beijing Natural Science Funds (Nos. 4144094), 863 programs (No. 2012AA121803), China Scholarship Council and CAS/SAFEA International Partnership Program for Creative Research Teams (No. KZZD-EW-TZ-05) and the State Key Laboratory of Geodesy and Earth’s Dynamics (Institute of Geodesy and Geophysics, CAS) (No: SKLGED2014-3-1-E). The authors would like to acknowledge the IGS Global Data Center CDDIS (Crustal Dynamics Data Information System, Greenbelt, MD, USA), iGMAS (international GNSS Monitoring and Assessment Service, Beijing, China), Center for Orbit Determination in Europe (CODE; University of Berne, Switzerland), Jet Propulsion Laboratory (JPL; Pasadena, California, USA), European Space Operations Center of European Space Agency (ESOC; Darmstadt, Germany), and Universitat Politècnica de Catalunya/IonSAT (UPC; Barcelona, Spain) for providing the data used in our experiment.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhanChina
  2. 2.Academy of Opto-ElectronicsChinese Academy of SciencesBeijingChina
  3. 3.Universitat Politecnica de Catalunya, UPC-IonSATBarcelonaSpain
  4. 4.University of Chinese Academy of SciencesBeijingChina

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