{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T14:06:25Z","timestamp":1782482785611,"version":"3.54.5"},"reference-count":33,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,10]],"date-time":"2019-12-10T00:00:00Z","timestamp":1575936000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Indoor positioning systems based on radio frequency inherently present multipath-related phenomena. This causes ranging systems such as ultra-wideband (UWB) to lose accuracy when detecting secondary propagation paths between two devices. If a positioning algorithm uses ranging measurements without considering these phenomena, it will face critical errors in estimating the position. This work analyzes the performance obtained in a localization system when combining location algorithms with machine learning techniques applied to a previous classification and mitigation of the propagation effects. For this purpose, real-world cross-scenarios are considered, where the data extracted from low-cost UWB devices for training the algorithms come from a scenario different from that considered for the test. The experimental results reveal that machine learning (ML) techniques are suitable for detecting non-line-of-sight (NLOS) ranging values in this situation.<\/jats:p>","DOI":"10.3390\/s19245438","type":"journal-article","created":{"date-parts":[[2019,12,10]],"date-time":"2019-12-10T10:52:41Z","timestamp":1575975161000},"page":"5438","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Environmental Cross-Validation of NLOS Machine Learning Classification\/Mitigation with Low-Cost UWB Positioning Systems"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8750-7960","authenticated-orcid":false,"given":"Valent\u00edn","family":"Barral","sequence":"first","affiliation":[{"name":"CITIC Research Center, Campus de Elvi\u00f1a, Universidade da Coru\u00f1a (University of A Coru\u00f1a), 15071 A Coru\u00f1a, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3877-1332","authenticated-orcid":false,"given":"Carlos J.","family":"Escudero","sequence":"additional","affiliation":[{"name":"CITIC Research Center, Campus de Elvi\u00f1a, Universidade da Coru\u00f1a (University of A Coru\u00f1a), 15071 A Coru\u00f1a, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1944-4678","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Garc\u00eda-Naya","sequence":"additional","affiliation":[{"name":"CITIC Research Center, Campus de Elvi\u00f1a, Universidade da Coru\u00f1a (University of A Coru\u00f1a), 15071 A Coru\u00f1a, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6956-8428","authenticated-orcid":false,"given":"Pedro","family":"Su\u00e1rez-Casal","sequence":"additional","affiliation":[{"name":"CITIC Research Center, Campus de Elvi\u00f1a, Universidade da Coru\u00f1a (University of A Coru\u00f1a), 15071 A Coru\u00f1a, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"404","DOI":"10.1109\/JPROC.2008.2008846","article-title":"Ranging with ultrawide bandwidth signals in multipath environments","volume":"97","author":"Dardari","year":"2009","journal-title":"Proc. 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