{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T22:24:54Z","timestamp":1780352694371,"version":"3.54.1"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,2,29]],"date-time":"2024-02-29T00:00:00Z","timestamp":1709164800000},"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>Broadband antennas with a low-profile generating circular polarization are always in demand for handheld\/ portable devices as CP antennas counter multipath and misalignment issues. Therefore, a compact millimeter-wave antenna is proposed in this article. The proposed antenna structure comprises two circular rings and a circular patch at the center. This structure is further embedded with four equilateral triangles at a 90\u00b0 orientation. The current entering the radiator is divided into left and right circular directions. The equilateral triangles provide the return path for current at the differential phase of \u00b190\u00b0, generating circular polarization. Structural development and analysis were initially performed through the characteristic mode theory. It showed that Modes 1 to 4 generated good impedance matching from 20 to 30 GHz and Modes 1 to 5, from 30 to 40 GHz. It also demonstrated the summation of orthogonal modes leading to circular polarization. The antenna-measured reflection coefficient |S11| &gt; 10 dB was 19 GHz (23\u201342 GHz), and the axial ratio at \u22123 dB was 4.2 GHz (36\u201340.2 GHz). The antenna gain ranged from 4 to 6.2 dBi. The proposed antenna was tested for link margin estimation for IoT indoor conditions with line-of-sight (LOS) and non-line-of-sight (NLOS) conditions. The communication reliability with co- and cross-polarization was also studied under these conditions, and the results proved to be satisfactory.<\/jats:p>","DOI":"10.3390\/s24051569","type":"journal-article","created":{"date-parts":[[2024,2,29]],"date-time":"2024-02-29T02:59:39Z","timestamp":1709175579000},"page":"1569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Low-Profile Circularly Polarized Millimeter-Wave Broadband Antenna Analyzed with a Link Budget for IoT Applications in an Indoor Scenario"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6757-8390","authenticated-orcid":false,"given":"Parveez Shariff","family":"Bhadravathi Ghouse","sequence":"first","affiliation":[{"name":"Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pallavi R.","family":"Mane","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1959-0480","authenticated-orcid":false,"given":"Tanweer","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Goutham Simha","family":"Golapuram Dattathreya","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8291-1275","authenticated-orcid":false,"given":"Sudheesh","family":"Puthenveettil Gopi","sequence":"additional","affiliation":[{"name":"Department of Electronics and Communication Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9867-4382","authenticated-orcid":false,"given":"Sameena","family":"Pathan","sequence":"additional","affiliation":[{"name":"Department of Information and Communication Technology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3364-342X","authenticated-orcid":false,"given":"Jaume","family":"Anguera","sequence":"additional","affiliation":[{"name":"Ignion, 08174 Barcelona, Spain"},{"name":"Research Group on Smart Society, La Salle Engineering, Universitat Romon Llull, 08022 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,2,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9597","DOI":"10.1109\/JIOT.2023.3235344","article-title":"Wideband Circularly Polarized Millimeter-Wave DRA Array for Internet of Things","volume":"10","author":"Attia","year":"2023","journal-title":"IEEE Internet Things J."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Aswal, D.K., Yadav, S., Takatsuji, T., Rachakonda, P., and Kumar, H. 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