{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,13]],"date-time":"2026-01-13T23:41:27Z","timestamp":1768347687282,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,12,1]],"date-time":"2022-12-01T00:00:00Z","timestamp":1669852800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007046","name":"Wuhan University","doi-asserted-by":"publisher","award":["20-01-09"],"award-info":[{"award-number":["20-01-09"]}],"id":[{"id":"10.13039\/501100007046","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007046","name":"Wuhan University","doi-asserted-by":"publisher","award":["BK20200664"],"award-info":[{"award-number":["BK20200664"]}],"id":[{"id":"10.13039\/501100007046","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007046","name":"Wuhan University","doi-asserted-by":"publisher","award":["17053FOSE"],"award-info":[{"award-number":["17053FOSE"]}],"id":[{"id":"10.13039\/501100007046","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["20-01-09"],"award-info":[{"award-number":["20-01-09"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["BK20200664"],"award-info":[{"award-number":["BK20200664"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["17053FOSE"],"award-info":[{"award-number":["17053FOSE"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"name":"University of Nottingham Ningbo China Faculty of Science and Engineering","award":["20-01-09"],"award-info":[{"award-number":["20-01-09"]}]},{"name":"University of Nottingham Ningbo China Faculty of Science and Engineering","award":["BK20200664"],"award-info":[{"award-number":["BK20200664"]}]},{"name":"University of Nottingham Ningbo China Faculty of Science and Engineering","award":["17053FOSE"],"award-info":[{"award-number":["17053FOSE"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ionospheric scintillation is one of the main error sources of Global Navigation Satellite System (GNSS) positioning. The presence of scintillation may result in cycle slips, measurement errors or even losses of lock on satellites, eventually leading to complete failure of positioning. Typically, scintillation parameters S4 and \u03c3\u03d5 are used to characterize amplitude and phase scintillation, respectively. However, the scintillation parameters can only be generated from data with a frequency of at least 1 Hz. Rate of change of total electron content index (ROTI) is often used as a proxy for scintillation parameters, which can be obtained from 1\/30 Hz data. However, previous research has shown the inefficiency of ROTI to represent scintillation. Therefore, the multipath parameter (MP) has been proposed as another proxy for scintillation parameters, which can also be obtained from 1\/30 Hz data. In this paper, both MP and ROTI (standard parameters) were used to mitigate scintillation effects on precise point positioning (PPP). To evaluate the effectiveness of MP and ROTI in mitigating scintillation effects, S4 and \u03c3\u03d5 were also used for comparison and validation. Three strategies are proposed: (1) remove all observations from the satellite that is most affected by scintillation; (2) remove the scintillation-affected observations; (3) weight the measurement noise matrix in the Kalman Filter (KF) process. The results show that the observation removal and weighting strategies are considerably more effective than the satellite removal strategy. The results also show that the improvement of PPP outputs reaches 93.1% and the performance of standard parameters is comparable to that of scintillation parameters in the observation removal and weighting strategies.<\/jats:p>","DOI":"10.3390\/rs14236089","type":"journal-article","created":{"date-parts":[[2022,12,1]],"date-time":"2022-12-01T03:57:28Z","timestamp":1669867048000},"page":"6089","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Mitigating the Scintillation Effect on GNSS Signals Using MP and ROTI"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1290-0693","authenticated-orcid":false,"given":"Chendong","family":"Li","sequence":"first","affiliation":[{"name":"Faculty of Science and Engineering, University of Nottingham, Ningbo 315100, China"}]},{"given":"Craig M.","family":"Hancock","sequence":"additional","affiliation":[{"name":"School of Architecture, Building and Civil Engineering, Loughborough University, Loughborough LE11 3TU, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3791-8096","authenticated-orcid":false,"given":"Sreeja","family":"Vadakke Veettil","sequence":"additional","affiliation":[{"name":"Nottingham Geospatial Institute, University of Nottingham, Nottingham NG7 2TU, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7297-8639","authenticated-orcid":false,"given":"Dongsheng","family":"Zhao","sequence":"additional","affiliation":[{"name":"NASG Key Laboratory of Land Environment and Disaster Monitoring, China University of Mining and Technology, Xuzhou 221116, China"},{"name":"School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5105-7846","authenticated-orcid":false,"given":"Nicholas A. S.","family":"Hamm","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, University of Nottingham, Ningbo 315100, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1002\/swe.20047","article-title":"Correlation of scintillation occurrence with interplanetary magnetic field reversals and impact on Global Navigation Satellite System receiver tracking performance","volume":"11","author":"Aquino","year":"2013","journal-title":"Space Weather"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Li, Q., Su, X., Xu, Y., Ma, H., Liu, Z., Cui, J., and Geng, T. (2022). Performance Analysis of GPS\/BDS Broadcast Ionospheric Models in Standard Point Positioning during 2021 Strong Geomagnetic Storms. 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