{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T23:19:19Z","timestamp":1773098359023,"version":"3.50.1"},"reference-count":58,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,11,24]],"date-time":"2022-11-24T00:00:00Z","timestamp":1669248000000},"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>Positioning systems are used in a wide range of applications which require determining the position of an object in space, such as locating and tracking assets, people and goods; assisting navigation systems; and mapping. Indoor Positioning Systems (IPSs) are used where satellite and other outdoor positioning technologies lack precision or fail. Ultra-WideBand (UWB) technology is especially suitable for an IPS, as it operates under high data transfer rates over short distances and at low power densities, although signals tend to be disrupted by various objects. This paper presents a comprehensive study of the precision, failure, and accuracy of 2D IPSs based on UWB technology and a pseudo-range multilateration algorithm using Time Difference of Arrival (TDoA) signals. As a case study, the positioning of a 4\u00d74m2 area, four anchors (transceivers), and one tag (receiver) are considered using bitcraze\u2019s Loco Positioning System. A Cram\u00e9r\u2013Rao Lower Bound analysis identifies the convex hull of the anchors as the region with highest precision, taking into account the anisotropic radiation pattern of the anchors\u2019 antennas as opposed to ideal signal distributions, while bifurcation envelopes containing the anchors are defined to bound the regions in which the IPS is predicted to fail. This allows the formulation of a so-called flyable area, defined as the intersection between the convex hull and the region outside the bifurcation envelopes. Finally, the static bias is measured after applying a built-in Extended Kalman Filter (EKF) and mapped using a Radial Basis Function Network (RBFN). A debiasing filter is then developed to improve the accuracy. Findings and developments are experimentally validated, with the IPS observed to fail near the anchors, precision around \u00b13cm, and accuracy improved by about 15cm for static and 5cm for dynamic measurements, on average.<\/jats:p>","DOI":"10.3390\/s22239136","type":"journal-article","created":{"date-parts":[[2022,11,25]],"date-time":"2022-11-25T03:34:24Z","timestamp":1669347264000},"page":"9136","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Analysis and Accuracy Improvement of UWB-TDoA-Based Indoor Positioning System"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1195-1859","authenticated-orcid":false,"given":"Paolo","family":"Grasso","sequence":"first","affiliation":[{"name":"Autonomous Vehicles & Artificial Intelligence Laboratory (AVAILAB), Centre for Future Transport and Cities, 7th Floor Friars House, Manor House Drive, Coventry CV1 2TE, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8836-2839","authenticated-orcid":false,"given":"Mauro S.","family":"Innocente","sequence":"additional","affiliation":[{"name":"Autonomous Vehicles & Artificial Intelligence Laboratory (AVAILAB), Centre for Future Transport and Cities, 7th Floor Friars House, Manor House Drive, Coventry CV1 2TE, UK"}]},{"given":"Jun Jet","family":"Tai","sequence":"additional","affiliation":[{"name":"Autonomous Vehicles & Artificial Intelligence Laboratory (AVAILAB), Centre for Future Transport and Cities, 7th Floor Friars House, Manor House Drive, Coventry CV1 2TE, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4665-2894","authenticated-orcid":false,"given":"Olivier","family":"Haas","sequence":"additional","affiliation":[{"name":"Centre for Future Transport and Cities, 7th Floor Friars House, Manor House Drive, Coventry CV1 2TE, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3377-6107","authenticated-orcid":false,"given":"Arash M.","family":"Dizqah","sequence":"additional","affiliation":[{"name":"Smart Vehicles Control Laboratory (SVeCLab), University of Sussex, Brighton BN1 9RH, UK"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"44413","DOI":"10.1109\/ACCESS.2022.3169267","article-title":"Precision Positioning for Smart Logistics Using Ultra-Wideband Technology-Based Indoor Navigation: A Review","volume":"10","author":"Elsanhoury","year":"2022","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1007\/s10846-021-01327-z","article-title":"A Survey of Machine Learning Techniques for Indoor Localization and Navigation Systems","volume":"101","author":"Roy","year":"2021","journal-title":"J. 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