{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T08:49:20Z","timestamp":1778662160627,"version":"3.51.4"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,6]],"date-time":"2023-01-06T00:00:00Z","timestamp":1672963200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Princess Nourah bint Abdulrahman University Researchers Supporting Project","award":["PNURSP2022R51"],"award-info":[{"award-number":["PNURSP2022R51"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A self-decoupled technique is described that enables the radiating elements in the antenna array to be densely packed for multiple-input multiple-output (MIMO) wireless communications systems. High isolation between the adjacent antenna elements is obtained by fixing the radiating elements in an orthogonal configuration with respects to each other. Current from the adjacent ports cancels their impact which results in low mutual coupling. The additional benefit of this configuration is realizing a densely packed array. The ground plane of each radiating element on the array board itself are isolated to mitigate surface wave propagations to suppress mutual coupling between the antenna elements. The radiating elements are based on a modified edge-fed circular patch antenna that includes a curved slot line and open-circuited stub to widen the array\u2019s impedance bandwidth with no impact on the antenna\u2019s footprint size. The proposed technique was verified with the design of an antenna array of matrix size 4 \u00d7 4 centered at 3.5 GHz. The array had a measured impedance bandwidth of 4 GHz from 1.5 GHz to 5.5 GHz, which corresponds to a fractional bandwidth of 114%, peak gain of 3 dBi and radiation efficiency of 84%. Its average diversity gain and envelope correlation coefficient (ECC) over its operating band are 9.6 dB and &lt;0.016, respectively. The minimum isolation achieved between the radiating elements is better than 15 dB. The dimensions of the array are 0.4 \u00d7 0.4 \u00d7 0.039\u03bb_g^3. The proposed array has characteristics suitable for sub-6 GHz wireless communication systems<\/jats:p>","DOI":"10.3390\/s23020654","type":"journal-article","created":{"date-parts":[[2023,1,6]],"date-time":"2023-01-06T03:54:49Z","timestamp":1672977289000},"page":"654","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["A Self-Decoupling Technique to Realize Dense Packing of Antenna Elements in MIMO Arrays for Wideband Sub-6 GHz Communication Systems"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4097-0928","authenticated-orcid":false,"given":"Shahid","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, COMSATS University Islamabad, Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1058-8920","authenticated-orcid":false,"given":"Safdar Nawaz Khan","family":"Marwat","sequence":"additional","affiliation":[{"name":"Department of Computer Systems Engineering, Faculty of Electrical and Computer Engineering, University of Engineering and Technology Peshawar, Peshawar 25120, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3669-2080","authenticated-orcid":false,"given":"Muhammad Amir","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Computer Science, COMSATS University, Islamabad-Abbottabad Campus, Abbottabad 22060, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0861-9823","authenticated-orcid":false,"given":"Salman","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Computer Systems Engineering, Faculty of Electrical and Computer Engineering, University of Engineering and Technology Peshawar, Peshawar 25120, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9792-0959","authenticated-orcid":false,"given":"Neelam","family":"Gohar","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Shaheed Benazir Bhutto Women University, Peshawar 25000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5040-4407","authenticated-orcid":false,"given":"Mohammad Ehsanul","family":"Alim","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, University of Delaware, Newark, DE 19716, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abeer D.","family":"Algarni","sequence":"additional","affiliation":[{"name":"Department of Information Technology, College of Computer and Information Sciences, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2571-1848","authenticated-orcid":false,"given":"Hela","family":"Elmannai","sequence":"additional","affiliation":[{"name":"Department of Information Technology, College of Computer and Information Sciences, Princess Nourah bint Abdulrahman University, P.O. Box 84428, Riyadh 11671, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1732","DOI":"10.1109\/TAP.2007.898618","article-title":"Reduction of mutual coupling between closely-packed antenna elements","volume":"55","author":"Chiu","year":"2007","journal-title":"IEEE Trans. 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