{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T15:00:35Z","timestamp":1777734035293,"version":"3.51.4"},"reference-count":37,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T00:00:00Z","timestamp":1611878400000},"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>The accuracy of the received signal strength-based visible light positioning (VLP) system in indoor applications is constrained by the tilt angles of transmitters (Txs) and receivers as well as multipath reflections. In this paper, for the first time, we show that tilting the Tx can be beneficial in VLP systems considering both line of sight (LoS) and non-line of sight transmission paths. With the Txs oriented towards the center of the receiving plane (i.e., the pointing center F), the received power level is maximized due to the LoS components on F. We also show that the proposed scheme offers a significant accuracy improvement of up to ~66% compared with a typical non-tilted Tx VLP at a dedicated location within a room using a low complex linear least square algorithm with polynomial regression. The effect of tilting the Tx on the lighting uniformity is also investigated and results proved that the uniformity achieved complies with the European Standard EN 12464-1. Furthermore, we show that the accuracy of VLP can be further enhanced with a minimum positioning error of 8 mm by changing the height of F.<\/jats:p>","DOI":"10.3390\/s21030920","type":"journal-article","created":{"date-parts":[[2021,1,29]],"date-time":"2021-01-29T11:34:33Z","timestamp":1611920073000},"page":"920","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["An Indoor Visible Light Positioning System Using Tilted LEDs with High Accuracy"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6255-2749","authenticated-orcid":false,"given":"Neha","family":"Chaudhary","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es and Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2015-1175","authenticated-orcid":false,"given":"Othman Isam","family":"Younus","sequence":"additional","affiliation":[{"name":"Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK"}]},{"given":"Luis Nero","family":"Alves","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es and Departamento de Electr\u00f3nica, Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5780-9703","authenticated-orcid":false,"given":"Zabih","family":"Ghassemlooy","sequence":"additional","affiliation":[{"name":"Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7902-2143","authenticated-orcid":false,"given":"Stanislav","family":"Zvanovec","sequence":"additional","affiliation":[{"name":"Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague, 16627 Prague, Czech Republic"}]},{"given":"Hoa","family":"Le-Minh","sequence":"additional","affiliation":[{"name":"Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"153479","DOI":"10.1109\/ACCESS.2020.3018140","article-title":"A Comprehensive Survey of Enabling and Emerging Technologies for Social Distancing\u2014Part I: Fundamentals and Enabling Technologies","volume":"8","author":"Nguyen","year":"2020","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2871","DOI":"10.1109\/COMST.2017.2743228","article-title":"Indoor Positioning Systems Based on Visible Light Communication: State of the Art","volume":"19","author":"Luo","year":"2017","journal-title":"IEEE Commun. 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