{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T13:53:28Z","timestamp":1774965208098,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2022,5,9]],"date-time":"2022-05-09T00:00:00Z","timestamp":1652054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Huawei Technologies (Sweden)","award":["WPTFZ"],"award-info":[{"award-number":["WPTFZ"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Energies"],"abstract":"<jats:p>Wireless power transfer promises to revolutionize the way in which we use and power mobile devices. However, low transfer efficiencies prevent this technology from seeing wide scale real-world adoption. The aim of this work is to use quasioptics to develop a system composed of a dielectric lens fed by a phased array to reduce spillover losses, increasing the beam efficiency, while working on the antenna system\u2019s Fresnel zone. The DC-RF electronics, digital beamforming and beam-steering by an FPGA, and radiating 4 \u00d7 4 microstrip patch phased array have been developed and experimented upon, while the lens has been designed and simulated. This paper details these preliminary results, where the phased array radiation pattern was measured, showing that the beam is being generated and steered as expected, prompting the lens construction for the complete system experimentation.<\/jats:p>","DOI":"10.3390\/en15093450","type":"journal-article","created":{"date-parts":[[2022,5,9]],"date-time":"2022-05-09T21:23:27Z","timestamp":1652131407000},"page":"3450","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Charging Mobile Devices in Indoor Environments"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6139-7924","authenticated-orcid":false,"given":"Diogo","family":"Matos","sequence":"first","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2983-3650","authenticated-orcid":false,"given":"Ricardo A. M.","family":"Pereira","sequence":"additional","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3851-4990","authenticated-orcid":false,"given":"Helena","family":"Ribeiro","sequence":"additional","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Bernardo","family":"Mendes","sequence":"additional","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5637-5691","authenticated-orcid":false,"given":"Daniel","family":"Belo","sequence":"additional","affiliation":[{"name":"Huawei Technologies Sweden AB, 16494 Kista, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8759-3456","authenticated-orcid":false,"given":"Arnaldo","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7402-2099","authenticated-orcid":false,"given":"Nuno Borges","family":"Carvalho","sequence":"additional","affiliation":[{"name":"Departamento de Eletr\u00f3nica Telecomunica\u00e7\u00f5es e Inform\u00e1tica, Instituto de Telecomunica\u00e7\u00f5es, Universidade de Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1230","DOI":"10.1109\/TMTT.1984.1132833","article-title":"The History of Power Transmission by Radio Waves","volume":"32","author":"Brown","year":"1984","journal-title":"IEEE Trans. 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