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Innovation Fund of Anhui University of Science and Technology","award":["gxbjZD2021088"],"award-info":[{"award-number":["gxbjZD2021088"]}]},{"name":"Graduate Innovation Fund of Anhui University of Science and Technology","award":["2021CX2070"],"award-info":[{"award-number":["2021CX2070"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>To satisfy the demand for 5G communication to smartphone terminal antennas in element quantity and isolation, an eight-element wideband MIMO antenna set of high isolation level is proposed. Each antenna element in the array is a double-L antenna consisting of an L-shaped slot and an L-shaped 50 \u03a9 microstrip line. The L slot is formed by adding an I-shaped open circuit directly to the side of the rectangular slot. In addition, the antenna arrays are located on the long bezels on both sides of the mobile phone motherboard, and the coupling feed is made in the frequency range of 3.6\u20134.7 GHz through the L-shaped microstrip line, so as to cover the 5G NR band (N77\/N78\/N79). Finally, the four element pairs (8 components) achieve isolation of greater than 11 dB, the performance frequency range is 3.6\u20134.7GHz, the return loss is \u22126 dB, the total efficiency is greater than 85%, and the envelope correlation coefficient is less than 0.08. Other MIMO performances are also calculated, the design process is discussed in detail, and one-handed grip mode and two-handed grip mode are discussed to demonstrate their stabilities in real-world applications.<\/jats:p>","DOI":"10.3390\/sym15030579","type":"journal-article","created":{"date-parts":[[2023,2,23]],"date-time":"2023-02-23T03:25:56Z","timestamp":1677122756000},"page":"579","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Design of MIMO Antenna with Double L-Shaped Structure for 5G NR"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5709-0727","authenticated-orcid":false,"given":"Zhonggen","family":"Wang","sequence":"first","affiliation":[{"name":"School of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan 232001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenshi","family":"You","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan 232001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ming","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Electrical and Communications Engineering, West Anhui University, Lu\u2019an, 237012, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenyan","family":"Nie","sequence":"additional","affiliation":[{"name":"School of Mechanical and Electrical Engineering, Huainan Normal University, Huainan 232001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8828-6087","authenticated-orcid":false,"given":"Weidong","family":"Mu","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan 232001, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1617","DOI":"10.1109\/COMST.2016.2532458","article-title":"Next Generation 5G Wireless Networks: A Comprehensive Survey","volume":"18","author":"Agiwal","year":"2016","journal-title":"IEEE Commun. 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