Journal of Radio Electronics. eISSN 1684-1719. 2025. ¹1
Full text in Russian (pdf)
DOI: https://doi.org/10.30898/1684-1719.2025.1.4
Features of Global electron content representation
in operational ionospheric models of Klobuchar,
C. Chen 1, A.M. Padokhin 1,2,3, A.K. Ivanov 1, I.A Pavlov 1,2,3
1 Faculty of Physics, Lomonosov Moscow State University, 119991, Moscow, Russia
2 Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation RAS, 108840, Moscow, Russia
3 Institute of Solar-Terrestrial Physics SB RAS, 664033, Irkutsk, Russia
The paper was received November 12, 2024.
Abstract. The article considers the features of ionospheric global electron content (GEC) estimation based on simple empirical models of Klobuchar, BDGIM and NeQuickG used in the global satellite navigation systems GPS, Beidou and Galileo. Using GNSS observational data for almost the entire 24th solar activity cycle and global ionospheric maps CODG, the statistics of deviations and spectral characteristics of GEC variations estimated in the models and observed experimentally are studied. It is shown that the average deviation and standard deviation of GEC estimates by the BDGIM and NeQuickG models from the CODG data are (-0.041GECu and 0.092GECu) and (-0.025GECu and 0.042GECu), respectively. Thus, the NeQuickG model can be used in applications requiring prompt GEC estimation. The BDGIM model gives comparable results, but the dispersion of deviations of the model GEC estimates from the experimentally observed ones is higher for it than for NeQuickG, especially during periods of maximum solar activity. The Klobuchar model gives significantly biased GEC estimates, both at the minimum (0.172GECu) and at the maximum of the 24th solar activity cycle (-0.243GECu) and cannot be recommended for estimating GEC. At the same time, the BDGIM model requires improvements in terms of reliable reproduction of the amplitudes of 27-day and semi-annual GEC variations, especially during periods of solar maximum, which in the future should also improve the accounting of the ionospheric delay in positioning tasks in the single-frequency mode.
Key words: ionosphere, GNSS, Global Electron Content, Klobuchar model, BDGIM, NeQuickG.
Financing: Russian Science Foundation project ¹ 23-17-00157.
Corresponding author: Padokhin Artem, padokhin@izmiran.ru
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For citation:
Chen C., Padokhin A.M., Ivanov A.K., Pavlov I.A. Features of GEC representation in operational ionospheric models of Klobuchar, BDGIM and NeQuickG // Journal of Radio Electronics. – 2025. – ¹. 1. https://doi.org/10.30898/1684-1719.2025.1.4 (In Russian)