An efficient regional ionospheric model using combined GPS/BeiDou observations

Abdelazeem M., Çelik R. N., El-Rabbany A.

JOURNAL OF SPATIAL SCIENCE, vol.62, no.2, pp.323-335, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Review
  • Volume: 62 Issue: 2
  • Publication Date: 2017
  • Doi Number: 10.1080/14498596.2016.1253512
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.323-335
  • Istanbul Technical University Affiliated: Yes


In this study, we develop a regional ionospheric model (RIM) based on the GPS-only observations and the combined GPS/BeiDou observations for single-frequency precise point positioning (SF-PPP) users in Europe. GPS/BeiDou observations from 16 reference stations are processed in the zero-differenced mode. A least-squares algorithm is developed to determine the total electron content (TEC) bi-linear function parameters for a 15-min time interval. The inverse distance weighted (IDW) interpolation technique is used to create the vertical TEC maps for a 1 degrees x1 degrees grid. The developed models are evaluated for PPP applications using GNSS observations from another set of reference stations. The SF-PPP accuracy and convergence time obtained through the RIMs are assessed and compared with those obtained through the International GNSS Service Global Ionospheric Maps (IGS-GIM). The results show that the RIMs accelerate the convergence time and improve the positioning accuracy in the horizontal and height components in comparison with the IGS-GIM counterparts.