{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,1,8]],"date-time":"2025-01-08T05:36:31Z","timestamp":1736314591465,"version":"3.32.0"},"reference-count":27,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2021,12,4]],"date-time":"2021-12-04T00:00:00Z","timestamp":1638576000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Competitiveness and Internationalization Operational Program (Compete2020)","award":["POCI-01-0247-FEDER-069770"]},{"name":"Regional Operational Program of Lisbon (Lisboa2020)","award":["LISBOA-01-0247-FEDER-069770"]},{"name":"Foundation for Science and Technology (FCT)","award":["UID\/EEA\/50008\/2021"]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"In this paper, a metamaterial-inspired flat beamsteering antenna for 5G applications is presented. The antenna, designed to operate in the 3.6 GHz at 5G frequency bands, presents an unique flat form factor which allows easy deployment and low visual impact in 5G dense scenarios. The antenna presents a multi-layer structure where a metamaterial inspired transmitarray enables the two-dimensional (2D) beamsteering, and an array of microstrip patch antennas is used as RF source. The use of metamaterials in antenna beamsteering allows the reduction of costly and complex phase-shifter networks by using discrete capacitor diodes to control the transmission phase-shifting and subsequently, the direction of the steering. According to simulations, the proposed antenna presents steering range up to \u00b120\u2218, achievable in both elevation and azimuth planes, independently. To prove the concept, a prototype of the antenna has been built and experimentally characterised inside an anechoic chamber. Although constructed in a different substrate (FR4 substrate) as initially designed, beamsteering ranges up to 8\u2218 in azimuth and 13\u2218 in elevation, limited to the proposed case-studies, are reported with the prototype, validating the antenna and the usefulness of the proposed design.<\/jats:p>","DOI":"10.3390\/s21238116","type":"journal-article","created":{"date-parts":[[2021,12,6]],"date-time":"2021-12-06T08:10:38Z","timestamp":1638778238000},"page":"8116","source":"Crossref","is-referenced-by-count":8,"title":["Metamaterial-Inspired Flat Beamsteering Antenna for 5G Base Stations at 3.6 GHz"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0356-9839","authenticated-orcid":false,"given":"Jo\u00e3o Ricardo","family":"Reis","sequence":"first","affiliation":[{"name":"Polytechnic of Leiria, 2411-901 Leiria, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 2411-901 Leiria, Portugal"}]},{"given":"M\u00e1rio","family":"Vala","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es, 2411-901 Leiria, Portugal"},{"name":"Instituto de Superior T\u00e9cnico, 1049-001 Lisbon, Portugal"}]},{"given":"Tiago Emanuel","family":"Oliveira","sequence":"additional","affiliation":[{"name":"Polytechnic of Leiria, 2411-901 Leiria, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 2411-901 Leiria, Portugal"}]},{"given":"Telmo Rui","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Polytechnic of Leiria, 2411-901 Leiria, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 2411-901 Leiria, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0297-7870","authenticated-orcid":false,"given":"Rafael Ferreira Silva","family":"Caldeirinha","sequence":"additional","affiliation":[{"name":"Polytechnic of Leiria, 2411-901 Leiria, Portugal"},{"name":"Instituto de Telecomunica\u00e7\u00f5es, 2411-901 Leiria, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"127639","DOI":"10.1109\/ACCESS.2019.2939938","article-title":"5G Evolution: A View on 5G Cellular Technology Beyond 3GPP Release 15","volume":"7","author":"Ghosh","year":"2019","journal-title":"IEEE Access"},{"key":"ref_2","unstructured":"3GPPgroup (2021, March 10). 5G\u20143GPP. 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