{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T04:18:32Z","timestamp":1780373912175,"version":"3.54.1"},"reference-count":28,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,5,6]],"date-time":"2019-05-06T00:00:00Z","timestamp":1557100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007480","name":"Universidad de Castilla-La Mancha","doi-asserted-by":"publisher","award":["2016\/14100"],"award-info":[{"award-number":["2016\/14100"]}],"id":[{"id":"10.13039\/501100007480","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["TIN2015-66972-C5-2-R"],"award-info":[{"award-number":["TIN2015-66972-C5-2-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["TIN2015-65686-C5-3-R"],"award-info":[{"award-number":["TIN2015-65686-C5-3-R"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Regional Council of Education, Culture and Sports of Castilla-La Mancha","award":["SBPLY\/17\/180501\/000493"],"award-info":[{"award-number":["SBPLY\/17\/180501\/000493"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>With the growing development of smartphones equipped with Wi-Fi technology and the need of inexpensive indoor location systems, many researchers are focusing their efforts on the development of Wi-Fi-based indoor localization methods. However, due to the difficulties in characterizing the Wi-Fi radio signal propagation in such environments, the development of universal indoor localization mechanisms is still an open issue. In this paper, we focus on the calibration of Wi-Fi-based indoor tracking systems to be used by smartphones. The primary goal is to build an accurate and robust Wi-Fi signal propagation representation in indoor scenarios.We analyze the suitability of our approach in a smartphone-based indoor tracking system by introducing a novel in-motion calibration methodology using three different signal propagation characterizations supplemented with a particle filter. We compare the results obtained with each one of the three characterization in-motion calibration methodologies and those obtained using a static calibration approach, in a real-world scenario. Based on our experimental results, we show that the use of an in-motion calibration mechanism considerably improves the tracking accuracy.<\/jats:p>","DOI":"10.3390\/rs11091072","type":"journal-article","created":{"date-parts":[[2019,5,9]],"date-time":"2019-05-09T08:19:59Z","timestamp":1557389999000},"page":"1072","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Calibration of Wi-Fi-Based Indoor Tracking Systems for Android-Based Smartphones"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6209-1695","authenticated-orcid":false,"given":"Miguel","family":"Mart\u00ednez del Horno","sequence":"first","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica (I3A), Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3451-7852","authenticated-orcid":false,"given":"Ismael","family":"Garc\u00eda-Varea","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica (I3A), Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Escuela Superior de Ingenier\u00eda Inform\u00e1tica (ESIIAB), Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1510-1608","authenticated-orcid":false,"given":"Luis","family":"Orozco Barbosa","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n en Inform\u00e1tica (I3A), Universidad de Castilla-La Mancha, 02071 Albacete, Spain"},{"name":"Escuela Superior de Ingenier\u00eda Inform\u00e1tica (ESIIAB), Universidad de Castilla-La Mancha, 02071 Albacete, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"715","DOI":"10.3390\/s150100715","article-title":"Fusion of WiFi, smartphone sensors and landmarks using the Kalman filter for indoor localization","volume":"15","author":"Chen","year":"2015","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1109\/MSP.2005.1458273","article-title":"Signal processing techniques in network-aided positioning: A survey of state-of-the-art positioning designs","volume":"22","author":"Sun","year":"2005","journal-title":"IEEE Signal Process. 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