<?xml version="1.0" encoding="utf-8"?>
<export-example>
  <doc>
    <id>6287</id>
    <completedYear/>
    <publishedYear>2025</publishedYear>
    <thesisYearAccepted/>
    <language>eng</language>
    <pageFirst>59</pageFirst>
    <pageLast>69</pageLast>
    <pageNumber>11</pageNumber>
    <edition/>
    <issue/>
    <volume>25</volume>
    <type>article</type>
    <publisherName>Copernicus GmbH</publisherName>
    <publisherPlace/>
    <creatingCorporation/>
    <contributingCorporation/>
    <belongsToBibliography>1</belongsToBibliography>
    <completedDate>--</completedDate>
    <publishedDate>--</publishedDate>
    <thesisDateAccepted>--</thesisDateAccepted>
    <title language="eng">Backscattering-Based Radiation Mode Analysis for Angle Estimation of a CRLH Leaky Wave Antenna</title>
    <abstract language="eng">Abstract. This study explores the extraction of the radiation mode field from backscattering field components of a composite right/left-handed (CRLH) leaky wave antenna (LWA) to estimate the relative angle to the radiation mode field within its frequency band of operation. Two methods, transmission line delay (TLD) and impedance loading (IL), for extracting the radiation mode from backscattering field components, are employed to isolate the radiation mode field of a CRLH LWA. In the IL method, backscattered fields are measured by terminating the CRLH LWA with short and open load impedances to express the radiation mode and structure mode field components. The TLD method uses a coaxial transmission line to connect the CRLH LWA to a high-gain X-band horn antenna, enabling isolation of the radiation mode field component from the backscattered field components, using time gating. This analysis employs two measurement setups for TLD, one in which both the CRLH LWA and the horn antenna rotate along the azimuth and the other in which only the CRLH LWA rotates. The analysis shows the frequency-angle relationship of the CRLH LWA radiation mode field, which reveals the frequency-dependent features of the CRLH LWA. Additionally, an evaluation of frequency ambiguity is done to provide more insights into the effectiveness of each approach for angle estimation of CRLH LWA relative to the incident wave.</abstract>
    <parentTitle language="eng">Advances in Radio Science</parentTitle>
    <identifier type="issn">1684-9973</identifier>
    <identifier type="doi">https://doi.org/10.5194/ars-23-59-2025</identifier>
    <enrichment key="opus_doi_flag">true</enrichment>
    <enrichment key="opus_import_data">{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T10:40:17Z","timestamp":1756464017169,"version":"3.44.0"},"reference-count":21,"publisher":"Copernicus GmbH","license":[{"start":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T00:00:00Z","timestamp":1756425600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Adv. Radio Sci."],"abstract":"&lt;jats:p&gt;Abstract. This study explores the extraction of the radiation mode field from backscattering field components of a composite right\/left-handed (CRLH) leaky wave antenna (LWA) to estimate the relative angle to the radiation mode field within its frequency band of operation. Two methods, transmission line delay (TLD) and impedance loading (IL), for extracting the radiation mode from backscattering field components, are employed to isolate the radiation mode field of a CRLH LWA. In the IL method, backscattered fields are measured by terminating the CRLH LWA with short and open load impedances to express the radiation mode and structure mode field components. The TLD method uses a coaxial transmission line to connect the CRLH LWA to a high-gain X-band horn antenna, enabling isolation of the radiation mode field component from the backscattered field components, using time gating. This analysis employs two measurement setups for TLD, one in which both the CRLH LWA and the horn antenna rotate along the azimuth and the other in which only the CRLH LWA rotates. The analysis shows the frequency-angle relationship of the CRLH LWA radiation mode field, which reveals the frequency-dependent features of the CRLH LWA. Additionally, an evaluation of frequency ambiguity is done to provide more insights into the effectiveness of each approach for angle estimation of CRLH LWA relative to the incident wave.\n                    &lt;\/jats:p&gt;","DOI":"10.5194\/ars-23-59-2025","type":"journal-article","created":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T10:07:51Z","timestamp":1756462071000},"page":"59-69","source":"Crossref","is-referenced-by-count":0,"title":["Backscattering-Based Radiation Mode Analysis for Angle Estimation of a CRLH Leaky Wave Antenna"],"prefix":"10.5194","volume":"23","author":[{"given":"Jeleel Alao","family":"Oladapo","sequence":"first","affiliation":[]},{"given":"Simon B.","family":"Adrian","sequence":"additional","affiliation":[]},{"given":"Mark A.","family":"Ebersp\u00e4cher","sequence":"additional","affiliation":[]}],"member":"3145","published-online":{"date-parts":[[2025,8,29]]},"reference":[{"key":"ref1","doi-asserted-by":"crossref","unstructured":"Appel-Hansen, J.: Accurate determination of gain and radiation patterns by radar cross-section measurements, IEEE T. Antenn. Propag., 27, 566\u2013570, https:\/\/doi.org\/10.1109\/TAP.1979.1142156, 1979.","DOI":"10.1109\/TAP.1979.1142156"},{"key":"ref2","unstructured":"Balanis, C. A.: Antenna Theory: Analysis and Design, 4th Edition, John Wiley &amp;amp;amp; Sons, Hoboken, NJ, USA, ISBN 9781118642061, 2016."},{"key":"ref3","doi-asserted-by":"crossref","unstructured":"Caloz, C. and Itoh, T.: Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications: The Engineering Approach, Wiley, https:\/\/doi.org\/10.1002\/0471754323, 2005.","DOI":"10.1002\/0471754323"},{"key":"ref4","doi-asserted-by":"crossref","unstructured":"Ebersp\u00e4cher, M. A. and Eibert, T. F.: Leaky wave antenna with amplitude controlled beam steering based on composite right\/left-handed transmission lines, Adv. Radio Sci., 8, 27\u201332, https:\/\/doi.org\/10.5194\/ars-8-27-2010, 2010.","DOI":"10.5194\/ars-8-27-2010"},{"key":"ref5","unstructured":"Green R. B.: The general theory of antenna scattering, Rep. 1223-17, Electro-Science Lab., Ohio State Univ., Columbus, OH, p. 11. Contract AF 33(616)-8039; AD 429 186, 1963."},{"key":"ref6","doi-asserted-by":"crossref","unstructured":"Harris, F. J.: On the use of windows for harmonic analysis with the discrete Fourier transform, Proc. IEEE, 66, 51\u201383, https:\/\/doi.org\/10.1109\/PROC.1978.10837, 1978.","DOI":"10.1109\/PROC.1978.10837"},{"key":"ref7","doi-asserted-by":"crossref","unstructured":"Ho, T. Y., Chen, S. Y., and Li, H. J.: A method to determine the structure mode and antenna mode of a RFID tag antenna scattering, IEEE Antennas Prop., 1\u20134, https:\/\/doi.org\/10.1109\/APS.2009.5171642, 2009.","DOI":"10.1109\/APS.2009.5171642"},{"key":"ref8","doi-asserted-by":"crossref","unstructured":"Huang, H.: Antenna sensors in passive wireless sensing systems, in: Handbook of Antenna Technologies, 4, https:\/\/doi.org\/10.1007\/978-981-4560-44-3_86, 2016.","DOI":"10.1007\/978-981-4560-44-3_86"},{"key":"ref9","doi-asserted-by":"crossref","unstructured":"Jiang, W., Liu, Y., Gong, S., and Hong, T.: Application of bionics in antenna radar cross section reduction, IEEE Antennas Wirel. Pr., 8, 127\u2013130, https:\/\/doi.org\/10.1109\/LAWP.2009.2037168, 2009.","DOI":"10.1109\/LAWP.2009.2037168"},{"key":"ref10","unstructured":"Johnson, R. C. and Jasik, H.: Antenna Engineering Handbook, 3rd Edition, McGraw-Hill, New York, NY, USA, ISBN 978-0070323810, 1993."},{"key":"ref11","doi-asserted-by":"crossref","unstructured":"Karmokar, D. K. and Guo, Y. J.: Planar leaky-wave antennas for low-cost radar, Proc. IEEE-APS Topical Conf. Antennas Propag. Wirel. Commun., 112\u2013115, https:\/\/doi.org\/10.1109\/APWC.2017.8062255, 2017.","DOI":"10.1109\/APWC.2017.8062255"},{"key":"ref12","doi-asserted-by":"crossref","unstructured":"Lambert, K. M., Rudduck, R. C., and Lee, T. H.: A new method for obtaining antenna gain from backscatter measurements, IEEE T. Antenn. Propag., 38, 739\u2013743, https:\/\/doi.org\/10.1109\/8.55588, 1990.","DOI":"10.1109\/8.55588"},{"key":"ref13","doi-asserted-by":"crossref","unstructured":"Lazaro, A., Ramos, A., Girbau, D., and Villarino, R.: A novel UWB RFID tag using active frequency selective surface, IEEE T. Antenn. Propag., 61, 1155\u20131165, https:\/\/doi.org\/10.1109\/TAP.2012.2228838, 2013.","DOI":"10.1109\/TAP.2012.2228838"},{"key":"ref14","doi-asserted-by":"crossref","unstructured":"Lindsey, J. F.: Radar cross-section effects relating to a horn antenna, IEEE T. Antenn. Propag., 37, 214\u2013218, https:\/\/doi.org\/10.1109\/8.18716, 1989.","DOI":"10.1109\/8.18716"},{"key":"ref15","unstructured":"Oladapo, J. A.: MATLAB code for Backscattering-Based Radiation Mode Analysis for Angle Estimation of a CRLH Leaky Wave Antenna, Figshare [code], https:\/\/doi.org\/10.6084\/m9.figshare.29973286, 2025a."},{"key":"ref16","unstructured":"Oladapo, J. A.: Measurement dataset for Backscattering-Based Radiation Mode Analysis for Angle Estimation of a CRLH Leaky Wave Antenna, Figshare [data set], https:\/\/doi.org\/10.6084\/m9.figshare.29973316, 2025b."},{"key":"ref17","doi-asserted-by":"crossref","unstructured":"Oladapo, J. A., Adrian, S. B., and Ebersp\u00e4cher, M. A.: Frequency-dependent RCS characterization of a CRLH-based leaky wave antenna, in: Proc. Kleinheubach Conf. 2024, Miltenberg, Germany, 23\u201325 September 2024, 1\u20134, https:\/\/doi.org\/10.23919\/IEEECONF64570.2024.10739083, 2024.","DOI":"10.23919\/IEEECONF64570.2024.10739083"},{"key":"ref18","doi-asserted-by":"crossref","unstructured":"Saeed, N. H., Farhan, M. J., and Al-Sherbaz, A.: Design and analysis of microstrip antenna for 5G applications, J. Eng. Sustain. Dev., 28, 163\u2013174, https:\/\/doi.org\/10.31272\/jeasd.28.2.10, 2024.","DOI":"10.31272\/jeasd.28.2.10"},{"key":"ref19","doi-asserted-by":"crossref","unstructured":"Suliman Munawar, H.: Applications of leaky-wave antennas: a review, Int. J. Wirel. Microwave Technol., 10, 56\u201362, https:\/\/doi.org\/10.5815\/ijwmt.2020.03.05, 2020.","DOI":"10.5815\/ijwmt.2020.03.05"},{"key":"ref20","doi-asserted-by":"crossref","unstructured":"Xu, F., Wu, K., and Zhang, X.: Periodic leaky-wave antenna for millimeter wave applications based on substrate integrated waveguide, IEEE T. Antenn. Propag., 58, 340\u2013347, https:\/\/doi.org\/10.1109\/TAP.2009.2026593, 2010.","DOI":"10.1109\/TAP.2009.2026593"},{"key":"ref21","doi-asserted-by":"crossref","unstructured":"Yang, S. T. and Ling, H.: RCS of a microstrip leaky-wave antenna, IEEE Antennas Wirel. Pr., 12, 35\u201338, https:\/\/doi.org\/10.1109\/LAWP.2012.2236677, 2013.","DOI":"10.1109\/LAWP.2012.2236677"}],"container-title":["Advances in Radio Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/ars.copernicus.org\/articles\/23\/59\/2025\/ars-23-59-2025.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,29]],"date-time":"2025-08-29T10:07:55Z","timestamp":1756462075000},"score":1,"resource":{"primary":{"URL":"https:\/\/ars.copernicus.org\/articles\/23\/59\/2025\/"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,8,29]]},"references-count":21,"URL":"https:\/\/doi.org\/10.5194\/ars-23-59-2025","relation":{"is-part-of":[{"id-type":"doi","id":"10.6084\/m9.figshare.29973316","asserted-by":"subject"},{"id-type":"doi","id":"10.6084\/m9.figshare.29973286","asserted-by":"subject"}]},"ISSN":["1684-9973"],"issn-type":[{"value":"1684-9973","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,8,29]]}}}</enrichment>
    <enrichment key="local_crossrefDocumentType">journal-article</enrichment>
    <enrichment key="local_crossrefLicence">https://creativecommons.org/licenses/by/4.0/</enrichment>
    <enrichment key="local_import_origin">crossref</enrichment>
    <enrichment key="local_doiImportPopulated">PersonAuthorFirstName_1,PersonAuthorLastName_1,PersonAuthorFirstName_2,PersonAuthorLastName_2,PersonAuthorFirstName_3,PersonAuthorLastName_3,PublisherName,TitleMain_1,Language,TitleAbstract_1,TitleParent_1,PageNumber,PageFirst,PageLast,Volume,PublishedYear,IdentifierIssn,Enrichmentlocal_crossrefLicence</enrichment>
    <enrichment key="opus.source">doi-import</enrichment>
    <author>Jeleel Alao Oladapo</author>
    <author>Simon B. Adrian</author>
    <author>Mark A. Eberspächer</author>
    <collection role="institutes" number="fe">Fakultät Elektrotechnik</collection>
  </doc>
</export-example>
