Approximation of ionosphere parameters using spherical functions
|1Yankiv-Vitkovska, LM, 1Dzhuman, BB |
1National University «Lviv Polytechnic», Lviv, Ukraine
|Space Sci.&Technol. 2018, 24 ;(6):74-79|
|Publication Language: Ukrainian|
The use of GNSS-technologies for ionospheric monitoring allows us to provide a study of global and regional phenomena in the ionosphere practically in real time. At the present stage, the restoration of the spatial distribution of VТЕС at the local and the regional scale is demanded, especially for solving and providing coordinate tasks. The model representation allows us to execute a spatial interpolation and, in some cases, an extrapolation of the VTEC values based on the initial data about the ionosphere parameter on the system of discrete points ¾ GNSS-stations. In this article, we present a method for approximating the VTEC ionosphere parameter.
We propose the system of spherical functions orthogonal on a spherical trapezium as a basic for approximating the regional field of the VTEC parameter. We substantiated the advantages of this method in comparison with the SCHA method. The used input data was the value of VTEC parameters for one epoch that was obtained after processing the data of 47 stations from the network of permanent GNSS-stations ZAKPOS. Estimation of the accuracy of the model was done. We assumed that the results obtained in this work could be applied to restore the spatial distribution of VTEC at the local and the regional scale, which is necessary for the correct solution of providing coordinate tasks.
|Keywords: ionosphere, spherical functions, spherical trapezium, VTEC parameter|
1. Yankiv-Vitkovska L. M. A procedure for the determination of ionosphere parameters on the basis of the GNSS network in the Western Ukraine. Kosm. nauka tekhnol.,19(6) : 47—52 (2013) [in Ukrainian].
2. Yankiv-Vitkovs'ka L. M. Metodyka userednennya danykh dlya pobudovy rehional'noyi modeli ionosfery. Heodeziya, kartohrafiya i aerofotoznimannya. Vyp. 79, 2014. S. 35—41 [in Ukrainian].
3. Abdelazeem M., Celik R., Rabbany A. EI. On the development of a regional ionospheric correction model for low-cost single frequency GNSS users. The 10th International conference on mobilemapping technology, Cairo, Egypt, 2017.
4. Dzhuman B. B. Modeling of the gravitational field on spherical trapezium. Geodesy, cartography and aerial photography, 2018. vol. 86. pp. 5—10.
5. Haines G. Spherical cap harmonic analysis. J. Geophys. Res., 1985, 90, 2583—2591.
6. Liu J., Chen R., An J., Wang Z., Hyyppa J. Spherical cap harmonic analysis of the Arctic ionospheric TEC for one solar cycle. J. Geophys. Res., vol. 119, pp. 601—619 (2014).
7. Ohashi M., Sato Y., Yamada A., Kubo Y., Sugimoto S. Studies on spherical cap harmonic analysis for Japanese regional ionospheric delays and its prediction. Proceedings of the 47th ISCIE International Symposiumon StochasticSystems Theory and Its Applications Honolulu, Dec. 5—8, 2015
8. Schaer S. Mapping and predicting the Earth’s ionosphere using the global positioning system / S. Schaer — PhD thesis, Astronomical Institute, University of Berne, Switzerland, 1999, 205 p.
9. Yankiv-Vitkovska L. M., Savchuk S. H., Matviichuk Ya. M., Pauchokand V. K., Bodnar D. I. Recovery of the spatial state of the ionosphere using regular definitions of the TEC identifier at the network of continuously operating GNSS stations of Ukraine. J.Geodesy and Geomatics Engineering 1, p. 37—47 (2016).