{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,9]],"date-time":"2025-12-09T08:26:07Z","timestamp":1765268767967,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,8]],"date-time":"2021-04-08T00:00:00Z","timestamp":1617840000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In this work, a novel rotation approach for the antenna elements of a linear phased array is presented. The proposed method improves by up to 14 dB the cross-polarization level within the main beam by performing a sequential 90\u00b0 rotation of the identical array elements, and achieving measured cross-polarization suppressions of 40 dB. This configuration is validated by means of simulation and measurements of a manufactured linear array of five dual-polarized cavity-box aperture coupled stacked patch antennas operating in L-Band, and considering both uniform amplitude and phase distribution and beamforming with amplitude tapering. The analysis is further extended by applying and comparing the proposed design with the 180\u00b0 rotation and non-rotation topologies. This technique is expected to be used for the next generation L-Band Airborne Synthetic Aperture Radar Sensor of the German Aerospace Center (DLR).<\/jats:p>","DOI":"10.3390\/rs13081430","type":"journal-article","created":{"date-parts":[[2021,4,8]],"date-time":"2021-04-08T21:27:44Z","timestamp":1617917264000},"page":"1430","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Sequential 90\u00b0 Rotation of Dual-Polarized Antenna Elements in Linear Phased Arrays with Improved Cross-Polarization Level for Airborne Synthetic Aperture Radar Applications"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7905-1294","authenticated-orcid":false,"given":"Diego","family":"Lorente","sequence":"first","affiliation":[{"name":"German Aerospace Center, Microwaves and Radar Institute, SAR-Technology, 82234 We\u00dfling, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3686-5535","authenticated-orcid":false,"given":"Markus","family":"Limbach","sequence":"additional","affiliation":[{"name":"German Aerospace Center, Microwaves and Radar Institute, SAR-Technology, 82234 We\u00dfling, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1477-1829","authenticated-orcid":false,"given":"Bernd","family":"Gabler","sequence":"additional","affiliation":[{"name":"German Aerospace Center, Microwaves and Radar Institute, SAR-Technology, 82234 We\u00dfling, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5936-658X","authenticated-orcid":false,"given":"H\u00e9ctor","family":"Esteban","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunicaciones y Aplicaciones Multimedia, Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7150-9785","authenticated-orcid":false,"given":"Vicente E.","family":"Boria","sequence":"additional","affiliation":[{"name":"Instituto de Telecomunicaciones y Aplicaciones Multimedia, Universitat Polit\u00e8cnica de Val\u00e8ncia, 46022 Valencia, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/j.isprsjprs.2014.08.004","article-title":"Spaceborne SAR data for global urban mapping at 30 m resolution using a robust urban extractor","volume":"103","author":"Ban","year":"2015","journal-title":"ISPRS J. 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