{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T06:15:25Z","timestamp":1769840125522,"version":"3.49.0"},"reference-count":31,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,3,24]],"date-time":"2021-03-24T00:00:00Z","timestamp":1616544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The ever-growing expectation for high data rates has led to the introduction of multiple-input multiple-output (MIMO) technologies to wireless connectivity. Such a system requires an MIMO antenna with high isolation. At the same time, the MIMO dimension should not be compromised for achieving high isolation. Thus, isolation techniques that do not allow an increase in dimension need to be fostered for MIMO antenna design. In this paper, a novel low-profile, miniaturized MIMO antenna with high isolation was developed considering a split ring resonator (SRR)-based bandstop filter as a decoupling network. The bandstop filter was designed with a unit cell split ring resonator structure and was deployed between two closely spaced monopole MIMO antenna elements to obtain isolation as high as 39.25 dB at 2.61 GHz. Two open-circuit stub lines were attached with the MIMO feeding network to achieve good impedance matching at resonance frequency. The proposed antenna exhibited a peak gain of 3.8 dBi and radiation efficiency of 84%. It had a low envelop correlation coefficient (ECC &lt; 0.12), high diversity gain (DG &gt; 9.95 dB), low mean effective gain ratio (MEG 1\/MEG 2 &lt; 0.05 dB), and low channel capacity loss (CCL &lt; 0.042 bits\/s\/Hz) at resonance frequency. The overall antenna dimension was restricted to 44\u00a0mm\u00a0\u00d722\u00a0mm\u00a0(0.38\u00a0\u03bb0\u00d70.19\u00a0\u03bb0) for its easy integration in compact wireless devices.<\/jats:p>","DOI":"10.3390\/s21072256","type":"journal-article","created":{"date-parts":[[2021,3,24]],"date-time":"2021-03-24T02:16:16Z","timestamp":1616552176000},"page":"2256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Split Ring Resonator-Based Bandstop Filter for Improving Isolation in Compact MIMO Antenna"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9239-3611","authenticated-orcid":false,"given":"Hashinur","family":"Islam","sequence":"first","affiliation":[{"name":"Department of Electronics and Communication Engineering, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India"}]},{"given":"Saumya","family":"Das","sequence":"additional","affiliation":[{"name":"Department of Information Technology, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1959-0480","authenticated-orcid":false,"given":"Tanweer","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Electronics &amp; Communication, Manipal institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India"}]},{"given":"Pradeep","family":"Kumar","sequence":"additional","affiliation":[{"name":"Discipline of Electrical, Electronic and Computer Engineering, University of KwaZulu-Natal, Durban 4041, South Africa"}]},{"given":"Sourav","family":"Dhar","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India"}]},{"given":"Tanushree","family":"Bose","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Sikkim 737136, India"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3650","DOI":"10.1109\/TAP.2008.2005469","article-title":"A decoupling technique for increasing the port isolation between two strongly coupled antennas","volume":"56","author":"Chen","year":"2008","journal-title":"IEEE Trans. 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