{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T16:41:48Z","timestamp":1778604108011,"version":"3.51.4"},"reference-count":25,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,9,27]],"date-time":"2024-09-27T00:00:00Z","timestamp":1727395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IPN-SIP","award":["20240839"],"award-info":[{"award-number":["20240839"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This article presents a symmetrical reduced-size eight-element MIMO antenna array with high electromagnetic isolation among radiators. The array utilizes easy-to-build techniques to cover the n77 and n78 new radio (NR) bands. It is based on an octagonal double-negative metamaterial split-ring resonator (SRR), which enables a size reduction of over 50% for the radiators compared to a conventional disc monopole antenna by increasing the slow-wave factor. Additionally, due to the extreme proximity between the radiating elements in the array, the modal significance (MS) method was employed to identify which propagation modes had the most impact on the electromagnetic coupling among elements. This approach aimed to mitigate their effect by using an electromagnetic barrier, thereby enhancing electromagnetic isolation. The electromagnetic barriers, implemented with strip lines, achieved isolation values exceeding 20 dB for adjacent elements (&lt;0.023 \u03bb) and approaching 40 dB for opposite ones (&lt;0.23 \u03bb) after analyzing the surface current distribution by the MS method. The elements are arranged in axial symmetry, forming an octagon with each antenna port located on a side. The array occupies an area of 0.32 \u03bb2 at 3.5 GHz, significantly smaller than previously published works. It exhibits excellent performance for MIMO applications, demonstrating an envelope correlation coefficient (ECC) below 0.0001, a total active reflection coefficient (TARC) lower than \u221210 dB for various incoming signals with random phases, and a diversity gain (DG) close to 20 dB.<\/jats:p>","DOI":"10.3390\/s24196266","type":"journal-article","created":{"date-parts":[[2024,9,27]],"date-time":"2024-09-27T11:19:33Z","timestamp":1727435973000},"page":"6266","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Small-Size Eight-Element MIMO Metamaterial Antenna with High Isolation Using Modal Significance Method"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3288-4416","authenticated-orcid":false,"given":"Tirado-Mendez","family":"Jose Alfredo","sequence":"first","affiliation":[{"name":"Instituto Polit\u00e9cnico Nacional, Electrical Engineering Department, SEPI-ESIME-Zacatenco, Av. IPN S\/N, Edif. 5., Ciudad de M\u00e9xico 07300, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4542-4961","authenticated-orcid":false,"given":"Jardon-Aguilar","family":"Hildeberto","sequence":"additional","affiliation":[{"name":"CINVESTAV-IPN, Telecommunications Section, Av. IPN 2508, San Pedro Zacatenco, Ciudad de M\u00e9xico 07360, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7584-0675","authenticated-orcid":false,"given":"Flores-Leal","family":"Ruben","sequence":"additional","affiliation":[{"name":"CINVESTAV-IPN, Telecommunications Section, Av. IPN 2508, San Pedro Zacatenco, Ciudad de M\u00e9xico 07360, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rangel-Merino","family":"Arturo","sequence":"additional","affiliation":[{"name":"Instituto Polit\u00e9cnico Nacional, Electrical Engineering Department, SEPI-ESIME-Zacatenco, Av. IPN S\/N, Edif. 5., Ciudad de M\u00e9xico 07300, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4349-0700","authenticated-orcid":false,"given":"Perez-Miguel","family":"Angel","sequence":"additional","affiliation":[{"name":"CINVESTAV-IPN, Telecommunications Section, Av. IPN 2508, San Pedro Zacatenco, Ciudad de M\u00e9xico 07360, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gomez-Villanueva","family":"Ricardo","sequence":"additional","affiliation":[{"name":"CINVESTAV-IPN, Telecommunications Section, Av. IPN 2508, San Pedro Zacatenco, Ciudad de M\u00e9xico 07360, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"154503","DOI":"10.1016\/j.aeue.2022.154503","article-title":"Quad-Band Two-Port MIMO Antenna Serving for Sub-7 GHz Frequency with Integrated Circularly Polarized Bands","volume":"160","author":"Sharma","year":"2023","journal-title":"AEU-Int. J. Electron. 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