{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T17:37:35Z","timestamp":1777657055940,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,3,5]],"date-time":"2024-03-05T00:00:00Z","timestamp":1709596800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Innovative Human Resource Development for Local Intellectualization Program","award":["IITP-2024-2020-0-01462"],"award-info":[{"award-number":["IITP-2024-2020-0-01462"]}]},{"name":"Institute of Information &amp; Communications Technology Planning &amp; Evaluation (IITP)","award":["IITP-2024-2020-0-01462"],"award-info":[{"award-number":["IITP-2024-2020-0-01462"]}]},{"name":"Korean Government","award":["IITP-2024-2020-0-01462"],"award-info":[{"award-number":["IITP-2024-2020-0-01462"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This paper presents a computer-simulation-based design of an in-line, coaxial-to-circular waveguide adapter for converting the coaxial transverse electromagnetic (TEM) mode to the circular waveguide TE11 mode over more than a one-octave bandwidth. The proposed adapter consists of a coaxial-to-rectangular waveguide transformer employing a stepped-ridge converter and a rectangular-to-circular waveguide transformer employing a curved transition. The proposed adapter has been optimized using a commercial simulation tool. The dimensions of the designed adapter are given so that it can be verified by anyone who is interested. The designed adapter operates from 8.00 GHz to 22.95 GHz (2.87:1 bandwidth) with a reflection coefficient of less than \u221220 dB and a higher-order mode level of less than \u221225.0 dB.<\/jats:p>","DOI":"10.3390\/sym16030304","type":"journal-article","created":{"date-parts":[[2024,3,5]],"date-time":"2024-03-05T03:03:20Z","timestamp":1709607800000},"page":"304","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Computational Design of an In-Line Coaxial-to-Circular Waveguide Adapter with More Than an Octave Bandwidth"],"prefix":"10.3390","volume":"16","author":[{"given":"Erdenesukh","family":"Altanzaya","sequence":"first","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiwon","family":"Heo","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8551-6863","authenticated-orcid":false,"given":"Songyuan","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2966-1200","authenticated-orcid":false,"given":"Chan-Soo","family":"Lee","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7977-8760","authenticated-orcid":false,"given":"Bierng-Chearl","family":"Ahn","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung-Soo","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Seong-Gon","family":"Choi","sequence":"additional","affiliation":[{"name":"School of Electric and Computer Engineering, Chungbuk National University, Cheongju 28644, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1002\/mmce.20428","article-title":"TM01 mode transducer using circular and rectangular waveguides","volume":"20","author":"Chakrabarty","year":"2010","journal-title":"Int. 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