{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T16:31:54Z","timestamp":1776357114263,"version":"3.51.2"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,9]],"date-time":"2024-01-09T00:00:00Z","timestamp":1704758400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62101562"],"award-info":[{"award-number":["62101562"]}]},{"name":"National Natural Science Foundation of China","award":["62271492"],"award-info":[{"award-number":["62271492"]}]},{"name":"National Natural Science Foundation of China","award":["62101566"],"award-info":[{"award-number":["62101566"]}]},{"name":"National Natural Science Foundation of China","award":["2022JJ10062"],"award-info":[{"award-number":["2022JJ10062"]}]},{"name":"Natural Science Foundation for Distinguished Young Scholars of Hunan Province","award":["62101562"],"award-info":[{"award-number":["62101562"]}]},{"name":"Natural Science Foundation for Distinguished Young Scholars of Hunan Province","award":["62271492"],"award-info":[{"award-number":["62271492"]}]},{"name":"Natural Science Foundation for Distinguished Young Scholars of Hunan Province","award":["62101566"],"award-info":[{"award-number":["62101566"]}]},{"name":"Natural Science Foundation for Distinguished Young Scholars of Hunan Province","award":["2022JJ10062"],"award-info":[{"award-number":["2022JJ10062"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Airborne circular synthetic aperture radar (CSAR) can realize high-resolution imaging of the scene over 360 degrees azimuth angle variation. Aiming at the problem of focusing of buildings for the airborne CSAR, this paper first analyzes the phase errors of CSAR buildings focusing in detail, and the analytic relationship between the scatterer height and azimuth focusing quality is deduced. Then, a focusing method of CSAR buildings based on the back projection algorithm is proposed. This method adopts the processing strategy of multi-layers imaging, and it is able to improve azimuth focusing quality of the buildings which have large height dimension. The proposed method is especially suitable for the high-resolution imaging and monitoring of the urban site with high-rise buildings in the airborne CSAR scenario. The correctness of the theoretical analysis and the validity of the proposed method are verified by using both simulation results and Ku-band airborne CSAR real data processing results.<\/jats:p>","DOI":"10.3390\/rs16020253","type":"journal-article","created":{"date-parts":[[2024,1,9]],"date-time":"2024-01-09T04:38:51Z","timestamp":1704775131000},"page":"253","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Focusing Method of Buildings for Airborne Circular SAR"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2713-7977","authenticated-orcid":false,"given":"Dong","family":"Feng","sequence":"first","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daoxiang","family":"An","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4840-9716","authenticated-orcid":false,"given":"Jian","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leping","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaotao","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1109\/MGRS.2013.2248301","article-title":"A tutorial on synthetic aperture radar","volume":"1","author":"Moreira","year":"2013","journal-title":"IEEE Geosci. 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