{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:42:22Z","timestamp":1787028142205,"version":"build-2736575974"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T00:00:00Z","timestamp":1659052800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Plan of China","award":["2021YFB3900801"],"award-info":[{"award-number":["2021YFB3900801"]}]},{"name":"National Key Research and Development Plan of China","award":["21477603D"],"award-info":[{"award-number":["21477603D"]}]},{"name":"Foundation of Technological Innovation Guidance Plan of Hebei","award":["2021YFB3900801"],"award-info":[{"award-number":["2021YFB3900801"]}]},{"name":"Foundation of Technological Innovation Guidance Plan of Hebei","award":["21477603D"],"award-info":[{"award-number":["21477603D"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Future Internet"],"abstract":"<jats:p>At present, the interaction mechanism between the complex indoor environment and pseudolite signals has not been fundamentally resolved, and the stability, continuity, and accuracy of indoor positioning are still technical bottlenecks. In view of the shortcomings of the existing indoor fingerprint positioning methods, this paper proposes a hybrid CSI fingerprint method for indoor pseudolite positioning based on Ray Tracing and artificial neural network (RT-ANN), which combines the advantages of actual acquisition, deterministic simulation, and artificial neural network, and adds the simulation CSI feature parameters generated by modeling and simulation to the input of the neural network, extending the sample features of the neural network input dataset. Taking an airport environment as an example, it is proved that the hybrid method can improve the positioning accuracy in the area where the fingerprints have been collected, the positioning error is reduced by 54.7% compared with the traditional fingerprint positioning method. It is also proved that preliminary positioning can be completed in the area without fingerprint collection.<\/jats:p>","DOI":"10.3390\/fi14080235","type":"journal-article","created":{"date-parts":[[2022,7,31]],"date-time":"2022-07-31T23:37:29Z","timestamp":1659310649000},"page":"235","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A CSI Fingerprint Method for Indoor Pseudolite Positioning Based on RT-ANN"],"prefix":"10.3390","volume":"14","author":[{"given":"Yaning","family":"Li","sequence":"first","affiliation":[{"name":"School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China"},{"name":"State Key Laboratory of Satellite Navigation System and Equipment Technology, Shijiazhuang 050081, China"},{"name":"The 54th Research Institute of China Electronics Technology Group Corporation, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hongsheng","family":"Li","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Engineering, Southeast University, Nanjing 210096, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Baoguo","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Navigation System and Equipment Technology, Shijiazhuang 050081, China"},{"name":"The 54th Research Institute of China Electronics Technology Group Corporation, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jun","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Satellite Navigation System and Equipment Technology, Shijiazhuang 050081, China"},{"name":"The 54th Research Institute of China Electronics Technology Group Corporation, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"153269","DOI":"10.1109\/ACCESS.2019.2948034","article-title":"A New Array Pseudolites Technology for High Precision Indoor Positioning","volume":"7","author":"Gan","year":"2019","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"38550","DOI":"10.1109\/ACCESS.2019.2905771","article-title":"Combination of Asynchronous Array Pseudolites and GNSS for Outdoor Localization","volume":"7","author":"Gan","year":"2019","journal-title":"IEEE Access"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Fan, G., Sheng, C., Yu, B., Huang, L., and Rong, Q. 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