{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,9,3]],"date-time":"2024-09-03T05:59:58Z","timestamp":1725343198471},"reference-count":33,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,7]],"date-time":"2018-04-07T00:00:00Z","timestamp":1523059200000},"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":"In this paper, we investigate relay-assisted visible light communications (VLC) where a mobile user acts as a relay and forwards data from a transmitter to the end mobile user. We analyse the utilization of the amplify-and-forward (AF) and decode-and-forward (DF) relaying schemes. The focus of the paper is on analysis of the behavior of the mobile user acting as a relay while considering a realistic locations of the receivers and transmitters on a standard mobile phone, more specifically with two photodetectors on both sides of a mobile phone and a transmitting LED array located upright. We also investigate dependency of the bit error rate (BER) performance on the azimuth and elevation angles of the mobile relay device within a typical office environment. We provide a new analytical description of BER for AF and DF-based relays in VLC. In addition we compare AF and DF-based systems and show that DF offers a marginal improvement in the coverage area with a BER < 10\u20133 and a data rate of 100 Mb\/s. Numerical results also illustrate that relay-based systems offer a significant improvement in terms of the coverage compared to direct non-line of sight VLC links.<\/jats:p>","DOI":"10.3390\/s18041125","type":"journal-article","created":{"date-parts":[[2018,4,10]],"date-time":"2018-04-10T17:06:08Z","timestamp":1523379968000},"page":"1125","source":"Crossref","is-referenced-by-count":22,"title":["Mobile User Connectivity in Relay-Assisted Visible Light Communications"],"prefix":"10.3390","volume":"18","author":[{"given":"Petr","family":"Pe\u0161ek","sequence":"first","affiliation":[{"name":"Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague, 2 Technicka, 16627 Prague, Czech Republic"}]},{"ORCID":"http:\/\/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, 2 Technicka, 16627 Prague, Czech Republic"}]},{"given":"Petr","family":"Chvojka","sequence":"additional","affiliation":[{"name":"Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague, 2 Technicka, 16627 Prague, Czech Republic"}]},{"given":"Manav","family":"Bhatnagar","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Indian Institute of Technology Delhi, Hauz Khas, IN-110016 New Delhi, India"}]},{"ORCID":"http:\/\/orcid.org\/0000-0002-5780-9703","authenticated-orcid":false,"given":"Zabih","family":"Ghassemlooy","sequence":"additional","affiliation":[{"name":"Optical Communications Research Group, NCRLab, Faculty of Engineering and Environment, Northumbria University, NE1 8ST Newcastle upon Tyne, UK"}]},{"given":"Prakriti","family":"Saxena","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, Indian Institute of Technology Delhi, Hauz Khas, IN-110016 New Delhi, India"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,7]]},"reference":[{"key":"ref_1","unstructured":"Barnett, T.J., Sumits, A., Jain, S., and Andra, U. 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