{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:17:22Z","timestamp":1760149042172,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,7,4]],"date-time":"2023-07-04T00:00:00Z","timestamp":1688428800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61971385"],"award-info":[{"award-number":["61971385"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper introduces a novel technique that uses observation data from GNSS to estimate the ionospheric vertical total electron content (VTEC) using the Kriging\u2013Kalman method. The technique provides a method to validate the accuracy of the Ionospheric VTEC analysis within the Equatorial Ionization anomaly region. The technique developed uses GNSS VTEC alongside solar parameters, such as solar radio flux (F10.7 cm), Disturbance Storm Time (Dst) and other data, and Long Short Term Memory (LSTM) Networks to predict the occurrence time of the ionospheric equatorial anomaly and ionospheric VTEC changes. The LSTM method was applied to GNSS data from Haikou Station. A comparison of this technique with the neural network (NN) model and International Reference Ionosphere model shows that the LSTM outperforms all of them at VTEC estimation and prediction. The results, which are based on the root mean square error (RMSE) between GNSS VTEC and GIM VTEC outside the equatorial anomaly region, was 1.42 TECU, and the results of GNSS VTEC and VTEC from Beidou geostationary orbit satellite, which lies inside the equatorial ionization anomaly region, was 1.92 TECU. The method developed can be used in VTEC prediction and estimation in real time space operations.<\/jats:p>","DOI":"10.3390\/rs15133394","type":"journal-article","created":{"date-parts":[[2023,7,4]],"date-time":"2023-07-04T01:47:14Z","timestamp":1688435234000},"page":"3394","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Novel Technique for High-Precision Ionospheric VTEC Estimation and Prediction at the Equatorial Ionization Anomaly Region: A Case Study over Haikou Station"],"prefix":"10.3390","volume":"15","author":[{"given":"Hai-Ning","family":"Wang","sequence":"first","affiliation":[{"name":"School of Automation, Northwestern Polytechnical University, Xi\u2019an 710072, China"},{"name":"China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]},{"given":"Qing-Lin","family":"Zhu","sequence":"additional","affiliation":[{"name":"China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]},{"given":"Xiang","family":"Dong","sequence":"additional","affiliation":[{"name":"China Research Institute of Radiowave Propagation, Qingdao 266107, China"},{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Dong-Sheng","family":"Sheng","sequence":"additional","affiliation":[{"name":"China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]},{"given":"Yong-Feng","family":"Zhi","sequence":"additional","affiliation":[{"name":"School of Automation, Northwestern Polytechnical University, Xi\u2019an 710072, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2692-9451","authenticated-orcid":false,"given":"Chen","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Bin","family":"Xu","sequence":"additional","affiliation":[{"name":"China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1360","DOI":"10.1002\/2016JA023727","article-title":"GPS detection of ionospheric Rayleigh wave and its source following the 2012 Haida Gwaii earthquake","volume":"122","author":"Jin","year":"2017","journal-title":"J. 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