{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,13]],"date-time":"2026-05-13T09:24:21Z","timestamp":1778664261303,"version":"3.51.4"},"reference-count":56,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,2,4]],"date-time":"2020-02-04T00:00:00Z","timestamp":1580774400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100010661","name":"Horizon 2020 Framework Programme","doi-asserted-by":"publisher","award":["H2020-MSCA-ITN-2016-SECRET-722424"],"award-info":[{"award-number":["H2020-MSCA-ITN-2016-SECRET-722424"]}],"id":[{"id":"10.13039\/100010661","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Electronics"],"abstract":"<jats:p>A compact four-element multiple-input multiple output (MIMO) antenna is proposed for medical applications operating at a 2.4 GHz ISM band. The proposed MIMO design occupies an overall volume of 26 mm \u00d7 26 mm \u00d7 0.8 mm. This antenna exhibits a good impedance matching at the operating frequency of the ISM band, whose performance attributes include: isolation around 25 dB, envelope correlation coefficient (ECC) less than 0.02, average channel capacity loss (CCL) less than 0.3 bits\/s\/Hz and diversity gain (DG) of around 10 dB. The average peak realized gain of the four-element MIMO antenna is 2.4 dBi with more than 77 % radiation efficiency at the frequency of interest (ISM 2.4 GHz). The compact volume and adequate bandwidth, as well as the good achieved gain, make this antenna a strong candidate for bio-medical wearable applications.<\/jats:p>","DOI":"10.3390\/electronics9020258","type":"journal-article","created":{"date-parts":[[2020,2,5]],"date-time":"2020-02-05T03:18:48Z","timestamp":1580872728000},"page":"258","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":56,"title":["Low-Profile and Closely Spaced Four-Element MIMO Antenna for Wireless Body Area Networks"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0440-8025","authenticated-orcid":false,"given":"Issa","family":"Elfergani","sequence":"first","affiliation":[{"name":"Mobile Systems Group, Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8312-7087","authenticated-orcid":false,"given":"Amjad","family":"Iqbal","sequence":"additional","affiliation":[{"name":"Centre For Wireless Technology, Faculty of Engineering, Multimedia University, Cyberjaya 63100, Malaysia"},{"name":"Department of Electrical Engineering, CECOS University of IT and Emerging Sciences, Peshawar 25000, Pakistan"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8179-4062","authenticated-orcid":false,"given":"Chemseddine","family":"Zebiri","sequence":"additional","affiliation":[{"name":"Department of Electronics, University of Ferhat Abbas, Setif -1-, 19000 Setif, Algeria"}]},{"given":"Abdul","family":"Basir","sequence":"additional","affiliation":[{"name":"Department of Telecommunication Engineering, UET Mardan 23200, Pakistan"}]},{"given":"Jonathan","family":"Rodriguez","sequence":"additional","affiliation":[{"name":"Mobile Systems Group, Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"},{"name":"Faculty of Computing, Engineering and Science, University of South Wales, Pontypridd CF37 1DL, UK"}]},{"given":"Maryam","family":"Sajedin","sequence":"additional","affiliation":[{"name":"Mobile Systems Group, Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"}]},{"given":"Artur de Oliveira","family":"Pereira","sequence":"additional","affiliation":[{"name":"Mobile Systems Group, Instituto de Telecomunica\u00e7\u00f5es, 3810-193 Aveiro, Portugal"}]},{"given":"Widad","family":"Mshwat","sequence":"additional","affiliation":[{"name":"School of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2972-9965","authenticated-orcid":false,"given":"Raed","family":"Abd-Alhameed","sequence":"additional","affiliation":[{"name":"School of Engineering and Informatics, University of Bradford, Bradford BD7 1DP, UK"},{"name":"Department of Communication and Informatics Engineering, Basra University College of Science and Technology, Basra 61004, Iraq"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5299-1577","authenticated-orcid":false,"given":"Sadiq","family":"Ullah","sequence":"additional","affiliation":[{"name":"Department of Telecommunication Engineering, UET Mardan 23200, Pakistan"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Elfergani, I., Hussaini, A.S., Rodriguez, J., and Abd-Alhameed, R. 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