{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T13:41:46Z","timestamp":1775050906708,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,11,27]],"date-time":"2017-11-27T00:00:00Z","timestamp":1511740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Polish National Center of Science","award":["UMO-2013\/11\/B\/ST10\/04709"],"award-info":[{"award-number":["UMO-2013\/11\/B\/ST10\/04709"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The ionosphere is still considered one of the most significant error sources in precise Global Navigation Satellite Systems (GNSS) positioning. On the other hand, new satellite signals and data processing methods allow for a continuous increase in the accuracy of the available ionosphere models derived from GNSS observables. Therefore, many research groups around the world are conducting research on the development of precise ionosphere products. This is also reflected in the establishment of several ionosphere-related working groups by the International Association of Geodesy. Whilst a number of available global ionosphere maps exist today, dense regional GNSS networks often offer the possibility of higher accuracy regional solutions. In this contribution, we propose an approach for regional ionosphere modelling based on un-differenced multi-GNSS carrier phase data for total electron content (TEC) estimation, and thin plate splines for TEC interpolation. In addition, we propose a methodology for ionospheric products self-consistency analysis based on calibrated slant TEC. The results of the presented approach are compared to well-established global ionosphere maps during varied ionospheric conditions. The initial results show that the accuracy of our regional ionospheric vertical TEC maps is well below 1 TEC unit, and that it is at least a factor of 2 better than the global products.<\/jats:p>","DOI":"10.3390\/rs9121221","type":"journal-article","created":{"date-parts":[[2017,11,27]],"date-time":"2017-11-27T11:07:08Z","timestamp":1511780828000},"page":"1221","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["Ionosphere Model for European Region Based on Multi-GNSS Data and TPS Interpolation"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6965-8420","authenticated-orcid":false,"given":"Anna","family":"Krypiak-Gregorczyk","sequence":"first","affiliation":[{"name":"Institute of Geodesy, University of Warmia and Mazury in Olsztyn, 19-719 Olsztyn, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5542-1481","authenticated-orcid":false,"given":"Pawel","family":"Wielgosz","sequence":"additional","affiliation":[{"name":"Institute of Geodesy, University of Warmia and Mazury in Olsztyn, 19-719 Olsztyn, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8283-4249","authenticated-orcid":false,"given":"Andrzej","family":"Borkowski","sequence":"additional","affiliation":[{"name":"Institute of Geodesy and Geoinformatics, Wroclaw University of Environmental and Life Sciences, 50-357 Wroclaw, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2017,11,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1002\/2014RS005466","article-title":"Ray tracing technique for global 3-D modeling of ionospheric electron density using GNSS measurements","volume":"50","author":"Alizadeh","year":"2015","journal-title":"Radio Sci."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Leick, A., Rapoport, L., and Tatarnikov, D. 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