{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T02:07:47Z","timestamp":1792462067258,"version":"4.5.0"},"reference-count":30,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2024,7,29]],"date-time":"2024-07-29T00:00:00Z","timestamp":1722211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundamental Research Funds for the Central Universities","award":["JG2023-53"],"award-info":[{"award-number":["JG2023-53"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["J2022-042"],"award-info":[{"award-number":["J2022-042"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["PHD2023-027"],"award-info":[{"award-number":["PHD2023-027"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["MHJY2023027"],"award-info":[{"award-number":["MHJY2023027"]}]},{"name":"Fundamental Research Funds for the Central Universities","award":["2023YFG0308"],"award-info":[{"award-number":["2023YFG0308"]}]},{"name":"Civil Aviation Professional Project","award":["JG2023-53"],"award-info":[{"award-number":["JG2023-53"]}]},{"name":"Civil Aviation Professional Project","award":["J2022-042"],"award-info":[{"award-number":["J2022-042"]}]},{"name":"Civil Aviation Professional Project","award":["PHD2023-027"],"award-info":[{"award-number":["PHD2023-027"]}]},{"name":"Civil Aviation Professional Project","award":["MHJY2023027"],"award-info":[{"award-number":["MHJY2023027"]}]},{"name":"Civil Aviation Professional Project","award":["2023YFG0308"],"award-info":[{"award-number":["2023YFG0308"]}]},{"name":"Sichuan Science and Technology Program","award":["JG2023-53"],"award-info":[{"award-number":["JG2023-53"]}]},{"name":"Sichuan Science and Technology Program","award":["J2022-042"],"award-info":[{"award-number":["J2022-042"]}]},{"name":"Sichuan Science and Technology Program","award":["PHD2023-027"],"award-info":[{"award-number":["PHD2023-027"]}]},{"name":"Sichuan Science and Technology Program","award":["MHJY2023027"],"award-info":[{"award-number":["MHJY2023027"]}]},{"name":"Sichuan Science and Technology Program","award":["2023YFG0308"],"award-info":[{"award-number":["2023YFG0308"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Non-line-of-sight (NLOS) errors significantly impact the accuracy of ultra-wideband (UWB) indoor positioning, posing a major barrier to its advancement. This study addresses the challenge of effectively distinguishing line-of-sight (LOS) from NLOS signals to enhance UWB positioning accuracy. Unlike existing research that focuses on optimizing deep learning network structures, our approach emphasizes the optimization of model parameters. We introduce a chaotic map for the initialization of the population and integrate a subtraction-average-based optimizer with a dynamic exploration probability to enhance the Snake Search Algorithm (SSA). This improved SSA optimizes the initial weights and thresholds of backpropagation (BP) neural networks for signal classification. Comparative evaluations with BP, Particle Swarm Optimizer\u2013BP (PSO-BP), and Snake Optimizer\u2013PB (SO-BP) models\u2014performed using three performance metrics\u2014demonstrate that our LTSSO-BP model achieves superior stability and accuracy, with classification accuracy, recall, and F1 score values of 90%, 91.41%, and 90.25%, respectively.<\/jats:p>","DOI":"10.3390\/s24154917","type":"journal-article","created":{"date-parts":[[2024,7,29]],"date-time":"2024-07-29T16:37:17Z","timestamp":1722271037000},"page":"4917","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Enhancing UWB Indoor Positioning Accuracy through Improved Snake Search Algorithm for NLOS\/LOS Signal Classification"],"prefix":"10.3390","volume":"24","author":[{"given":"Fang","family":"Wang","sequence":"first","affiliation":[{"name":"School of Science, Civil Aviation Flight University of China, Guanghan 618307, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lingqiao","family":"Shui","sequence":"additional","affiliation":[{"name":"School of Computer Science, Civil Aviation Flight University of China, Guanghan 618307, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hai","family":"Tang","sequence":"additional","affiliation":[{"name":"School of Computer Science, Civil Aviation Flight University of China, Guanghan 618307, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhe","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Computer Science, Civil Aviation Flight University of China, Guanghan 618307, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4028","DOI":"10.1109\/TIM.2018.2884605","article-title":"Human body shadowing effect on UWB-based ranging system for pedestrian tracking","volume":"68","author":"Tian","year":"2019","journal-title":"IEEE Trans. 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