{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T08:42:40Z","timestamp":1772786560528,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,6,16]],"date-time":"2023-06-16T00:00:00Z","timestamp":1686873600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Due to the lack of coverage of IGS in Africa, especially over North Africa, and the construction revolution of infrastructure in Egypt, a geodetic CORS stations network was established in 2012. These CORS stations are operated by the Egyptian Surveying Authority (Egy. SA) and cover the whole of Egypt. The paper presents a fully developed regional ionosphere model (RIM) depending on the Egyptian CORS stations. The new model and the PPP solution were obtained using Bernese GNSS V. 5.2 software. An observation data series of eight days (DOY 201\u2013208)\/2019 was used in this study. Eighteen stations were used to develop the RIM model for each day; fifteen stations were used to validate the new RIM model. A static SF-PPP solution was obtained using the CODE-GIM and RIM models. Comparing the outcomes to the reference network solution, based on the recently developed RIM model, the solution showed a mean error of 0.06 m in the East direction, 0.13 m in the North direction, and 0.21 m in the height direction. In the East, North, and height directions, this solution improves the SF-PPP result achieved by the Global Ionosphere Maps (CODE-GIM) model by 60%, 68%, and 77%, respectively.<\/jats:p>","DOI":"10.3390\/rs15123147","type":"journal-article","created":{"date-parts":[[2023,6,16]],"date-time":"2023-06-16T08:56:01Z","timestamp":1686905761000},"page":"3147","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Method of Development of a New Regional Ionosphere Model (RIM) to Improve Static Single-Frequency Precise Point Positioning (SF-PPP) for Egypt Using Bernese GNSS Software"],"prefix":"10.3390","volume":"15","author":[{"given":"Ashraf","family":"Abdallah","sequence":"first","affiliation":[{"name":"Faculty of Engineering, Aswan University, Aswan 81528, Egypt"},{"name":"Institute of Engineering Geodesy (IIGS), Stuttgart University, 70174 Stuttgart, Germany"}]},{"given":"Tarek","family":"Agag","sequence":"additional","affiliation":[{"name":"Egyptian Surveying Authority, Orman P.O. Box 63, Giza 12612, Egypt"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9055-9809","authenticated-orcid":false,"given":"Volker","family":"Schwieger","sequence":"additional","affiliation":[{"name":"Institute of Engineering Geodesy (IIGS), Stuttgart University, 70174 Stuttgart, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Seeber, G. (2003). Satellite Geodesy, Walter de Gruyter. [2nd ed.].","DOI":"10.1515\/9783110200089"},{"key":"ref_2","unstructured":"Misra, P., and Enge, P. (2012). Global Positioning System: Signals, Measurements, and Performance, Ganga-Jumana Press. [2nd ed.]."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1109\/TAES.1987.310829","article-title":"Ionospheric time-delay algorithm for single-frequency GPS users","volume":"3","author":"Klobuchar","year":"1987","journal-title":"IEEE Trans. Aerosp. Electron. 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