{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T15:13:23Z","timestamp":1776784403827,"version":"3.51.2"},"reference-count":39,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,16]],"date-time":"2021-04-16T00:00:00Z","timestamp":1618531200000},"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>In this paper, we propose and validate an artificial neural network-based equalizer for the constant power 4-level pulse amplitude modulation in an optical camera communications system. We introduce new terminology to measure the quality of the communications link in terms of the number of row pixels per symbol Npps, which allows a fair comparison considering the progress made in the development of the current image sensors in terms of the frame rates and the resolutions of each frame. Using the proposed equalizer, we experimentally demonstrate a non-flickering system using a single light-emitting diode (LED) with Npps of 20 and 30 pixels\/symbol for the unequalized and equalized systems, respectively. Potential transmission rates of up to 18.6 and 24.4 kbps are achieved with and without the equalization, respectively. The quality of the received signal is assessed using the eye-diagram opening and its linearity and the bit error rate performance. An acceptable bit error rate (below the forward error correction limit) and an improvement of ~66% in the eye linearity are achieved using a single LED and a typical commercial camera with equalization.<\/jats:p>","DOI":"10.3390\/s21082826","type":"journal-article","created":{"date-parts":[[2021,4,19]],"date-time":"2021-04-19T21:59:49Z","timestamp":1618869589000},"page":"2826","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["The Utilization of Artificial Neural Network Equalizer in Optical Camera Communications"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2015-1175","authenticated-orcid":false,"given":"Othman Isam","family":"Younus","sequence":"first","affiliation":[{"name":"Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK"}]},{"given":"Navid Bani","family":"Hassan","sequence":"additional","affiliation":[{"name":"Institute of Photonics, University of Strathclyde, Glasgow G1 1XQ, UK"}]},{"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"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8071-9546","authenticated-orcid":false,"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"}]},{"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":[[2021,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"24082","DOI":"10.1364\/OE.27.024082","article-title":"Performance evaluation of neural network assisted motion detection schemes implemented within indoor optical camera based communications","volume":"27","author":"Teli","year":"2019","journal-title":"Opt. 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