{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T14:49:31Z","timestamp":1774536571659,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T00:00:00Z","timestamp":1655078400000},"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>A circularly polarized (CP) multi-input multioutput (MIMO) dielectric resonator (DR) antenna (DRA) with compact size and four ports is implemented. CP radiation was achieved using the deformed DR geometry excited with aperture coupled feeding. A CPDRA with a single and two ports is investigated. The defected ground structure (DGS) was incorporated into the antenna for improving the isolation between the ports. The DGS was incorporated in such a way that the required phase difference between the generated orthogonal degenerate modes is preserved. This concept could be utilized in implementing a compact four-port CP antenna. The MIMO antenna provides a 10 dB impedance bandwidth of 38% (8.5\u201312.5 GHz) and a 3 dB AR bandwidth of 9.32% (9.2\u201310.1 GHz). The gain of the implemented antenna was around 6 dBi in the band where CP radiation was achieved. The MIMO performance parameters were calculated, and their values remained within the acceptable limits. The implemented antenna could suitably be used in X-band applications.<\/jats:p>","DOI":"10.3390\/s22124461","type":"journal-article","created":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T06:31:59Z","timestamp":1655101919000},"page":"4461","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Compact Four-Port Circularly Polarized MIMO X-Band DRA"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7122-0770","authenticated-orcid":false,"given":"Ahmed A.","family":"Ibrahim","sequence":"first","affiliation":[{"name":"Electronics and Communications Engineering Department, Minia University, El-Minia 61519, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hijab","family":"Zahra","sequence":"additional","affiliation":[{"name":"School of Engineering, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6390-0896","authenticated-orcid":false,"given":"Syed Muzahir","family":"Abbas","sequence":"additional","affiliation":[{"name":"School of Engineering, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7485-9406","authenticated-orcid":false,"given":"Mohamed I.","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Microstrip Department, Electronics Research Institute, El Nozha, Cairo 11843, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gaurav","family":"Varshney","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, National Institute of Technology Patna, Patna 800005, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8600-5907","authenticated-orcid":false,"given":"Subhas","family":"Mukhopadhyay","sequence":"additional","affiliation":[{"name":"School of Engineering, Faculty of Science and Engineering, Macquarie University, Sydney, NSW 2109, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9002-4860","authenticated-orcid":false,"given":"Abdelhady","family":"Mahmoud","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, Benha University, Benha 13511, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1049\/ip-h-2.1992.0016","article-title":"Theoretical and experimental resonant frequencies of rectangular dielectric resonators","volume":"139","author":"Mongia","year":"1992","journal-title":"IEE Proc. H Microw. Antennas Propag."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1109\/LAWP.2019.2957288","article-title":"Broadband Folded Reflectarray Fed by a Dielectric Resonator Antenna","volume":"19","author":"Yang","year":"2020","journal-title":"IEEE Antennas Wirel. Propag. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1049\/iet-map.2016.0457","article-title":"Dielectric resonator based MIMO antenna system enabling millimetre-wave mobile devices","volume":"11","author":"Sharawi","year":"2017","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1109\/MAP.2017.2658346","article-title":"Current Misuses and Future Prospects for Printed Multiple-Input, Multiple-Output Antenna Systems","volume":"59","author":"Sharawi","year":"2017","journal-title":"IEEE Antenna Propag. Mag."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"4457","DOI":"10.1109\/TAP.2021.3060034","article-title":"Hybrid Dielectric Resonator Antenna for Diversity Applications with Linear or Circular Polarization","volume":"69","author":"Kuznetcov","year":"2021","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"153172","DOI":"10.1016\/j.aeue.2020.153172","article-title":"Triple band MIMO dielectric resonator antenna for LTE applications","volume":"118","author":"Anuar","year":"2020","journal-title":"AEU Int. J. Electron. Commun."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3811","DOI":"10.1109\/TAP.2020.3048502","article-title":"Circularly Polarized MIMO Dielectric Resonator Antenna with Reduced Mutual Coupling","volume":"69","author":"Hu","year":"2020","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2224","DOI":"10.1109\/TAP.2019.2891456","article-title":"A Simple Decoupling Method for 5G Millimeter-Wave MIMO Dielectric Resonator Antennas","volume":"67","author":"Pan","year":"2019","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"747","DOI":"10.1109\/LAWP.2019.2901961","article-title":"A MIMO Dielectric Resonator Antenna with Improved Isolation for 5G mm-Wave Applications","volume":"18","author":"Zhang","year":"2019","journal-title":"IEEE Antennas Wirel. Propag. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"40951","DOI":"10.1109\/ACCESS.2019.2908001","article-title":"Mutual Coupling Reduction Using Hybrid Technique in Wideband Circularly Polarized MIMO Antenna for WiMAX Applications","volume":"7","author":"Iqbal","year":"2019","journal-title":"IEEE Access"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2193","DOI":"10.1049\/iet-map.2018.5799","article-title":"Compact four-port MIMO dielectric resonator antenna with pattern diversity","volume":"13","author":"Varshney","year":"2019","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_12","first-page":"e22350","article-title":"Dual-band circularly polarized MIMO DRA for sub-6 GHz applications","volume":"30","author":"Singhwal","year":"2020","journal-title":"Int. J. RF Microw. Comput. Eng."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1990","DOI":"10.1080\/09205071.2020.1801522","article-title":"Design of dual band four port circularly polarized MIMO DRA for WLAN\/WiMAX applications","volume":"34","author":"Dwivedi","year":"2020","journal-title":"J. Electromagn. Waves Appl."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"140889","DOI":"10.1109\/ACCESS.2019.2943880","article-title":"A Compact Circularly Polarized MIMO Dielectric Resonator Antenna Over Electromagnetic Band-Gap Surface for 5G Applications","volume":"7","author":"Chen","year":"2019","journal-title":"IEEE Access"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1049\/iet-map.2018.6112","article-title":"Super-wideband multi-input\u2013multi-output dielectric resonator antenna","volume":"14","author":"Gotra","year":"2019","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"19","DOI":"10.2528\/PIERM20011003","article-title":"Circularly Polarized Two-Port Mimo Dielectric Resonator Antenna","volume":"91","author":"Varshney","year":"2020","journal-title":"Prog. Electromagn. Res. M"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1323","DOI":"10.1049\/iet-map.2019.0932","article-title":"Gain and bandwidth enhancement of a singly-fed circularly polarised dielectric resonator antenna","volume":"14","author":"Varshney","year":"2020","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_18","first-page":"e22638","article-title":"An array of staircase-shaped circularly polarized DRA","volume":"31","author":"Mahmoud","year":"2021","journal-title":"Int. J. RF Microw. Comput. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"4901","DOI":"10.1016\/j.aej.2020.09.005","article-title":"Wideband circularly polarized aperture coupled DRA array with sequential-phase feed at X-band","volume":"59","author":"Ibrahim","year":"2020","journal-title":"Alex. Eng. J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2067","DOI":"10.1109\/TAP.2018.2800799","article-title":"Inverted-Sigmoid Shaped Multiband Dielectric Resonator Antenna with Dual-Band Circular Polarization","volume":"66","author":"Varshney","year":"2018","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1868","DOI":"10.1049\/iet-map.2017.0244","article-title":"Dual-band fan-blade-shaped circularly polarised dielectric resonator antenna","volume":"11","author":"Varshney","year":"2017","journal-title":"IET Microw. Antennas Propag."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1109\/TAP.2015.2392131","article-title":"A New Wideband Circularly Polarized Stair-Shaped Dielectric Resonator Antenna","volume":"63","author":"Fakhte","year":"2015","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1380","DOI":"10.1109\/TAP.2016.2635619","article-title":"Wide Band Circularly Polarized Dielectric Resonator Antenna with Stair-Shaped Slot Excitation","volume":"65","author":"Varshney","year":"2017","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2112","DOI":"10.1109\/TAP.2010.2046851","article-title":"Dual-Band Circularly Polarized $S$-Shaped Slotted Patch Antenna with a Small Frequency-Ratio","volume":"58","author":"Nasimuddin","year":"2010","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2855","DOI":"10.1002\/mop.31416","article-title":"Dielectric resonator-based wide band circularly polarized MIMO antenna with pattern diversity for WLAN applications","volume":"60","author":"Sahu","year":"2018","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"153990","DOI":"10.1016\/j.aeue.2021.153990","article-title":"High gain, wideband and low mutual coupling AMC-based millimeter wave MIMO antenna for 5G NR networks","volume":"142","author":"Ibrahim","year":"2021","journal-title":"AEU Int. J. Electron. Commun."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Zahra, H., Awan, W., Ali, W., Hussain, N., Abbas, S., and Mukhopadhyay, S. (2021). A 28 GHz Broadband Helical Inspired End-Fire Antenna and Its MIMO Configuration for 5G Pattern Diversity Applications. Electronics, 10.","DOI":"10.3390\/electronics10040405"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1616","DOI":"10.1109\/LAWP.2021.3091644","article-title":"An Arrangement for Four-Element MIMO DRA with Complementary CP Diversity","volume":"20","author":"Sahu","year":"2021","journal-title":"IEEE Antennas Wirel. Propag. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"99","DOI":"10.2528\/PIERL19031304","article-title":"Four Element Mimo dra with High Isolation for Wlan Applications","volume":"84","author":"Sarkar","year":"2019","journal-title":"Prog. Electromagn. Res. Lett."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"884","DOI":"10.1049\/el.2018.0959","article-title":"Compact back-to-back DRA-based four-port MIMO antenna system with bi-directional diversity","volume":"54","author":"Das","year":"2018","journal-title":"Electron. Lett."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/12\/4461\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:28:38Z","timestamp":1760138918000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/12\/4461"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,6,13]]},"references-count":30,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2022,6]]}},"alternative-id":["s22124461"],"URL":"https:\/\/doi.org\/10.3390\/s22124461","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,6,13]]}}}