{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:47:44Z","timestamp":1760402864740,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,13]],"date-time":"2022-01-13T00:00:00Z","timestamp":1642032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61971042","11833001","61931002"],"award-info":[{"award-number":["61971042","11833001","61931002"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004826","name":"Beijing Natural Science Foundation","doi-asserted-by":"publisher","award":["4202067"],"award-info":[{"award-number":["4202067"]}],"id":[{"id":"10.13039\/501100004826","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Extremely-high-squint (EHS) geometry of the traditional constant-parameter synthetic aperture radar (SAR) induces non-orthogonal wavenumber spectrum and hence the distortion of point spread function (PSF) in focused images. The method invented to overcome this problem is referred to as new-concept parameter-adjusting SAR. It corrects the PSF distortion by adjusting radar parameters, such as carrier frequency and chirp rate, based on instant data acquisition geometry. In this case, the characteristic of signal is quite different from the constant-parameter SAR and therefore, the traditional imaging algorithms cannot be directly applied for parameter-adjusting SAR imaging. However, the existing imaging algorithm for EHS parameter-adjusting SAR suffers from insufficient accuracy if a high-resolution wide-swath (HRWS) performance is required. Thus, this paper proposes a multi-layer overlapped subaperture algorithm (ML-OSA) for EHS HRWS parameter-adjusting SAR imaging with three main contributions: First, a more accurate signal model with time-varying radar parameters in high-squint geometry is derived. Second, phase errors are compensated with much higher accuracy by implementing multiple layers of coarse-to-fine spatially variant filters. Third, the analytical swath limit of the ML-OSA is derived by considering both the residual errors of signal model and phase compensations. The presented approach is validated via both the point- and extended-target computer simulations.<\/jats:p>","DOI":"10.3390\/rs14020365","type":"journal-article","created":{"date-parts":[[2022,1,14]],"date-time":"2022-01-14T03:14:03Z","timestamp":1642130043000},"page":"365","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Multi-Layer Overlapped Subaperture Algorithm for Extremely-High-Squint High-Resolution Wide-Swath SAR Imaging with Continuously Time-Varying Radar Parameters"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2540-5824","authenticated-orcid":false,"given":"Yan","family":"Wang","sequence":"first","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Chongqing Innovation Center, Beijing Institute of Technology, Chongqing 401331, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7573-4696","authenticated-orcid":false,"given":"Rui","family":"Min","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2967-4936","authenticated-orcid":false,"given":"Zegang","family":"Ding","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Chongqing Innovation Center, Beijing Institute of Technology, Chongqing 401331, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2513-6014","authenticated-orcid":false,"given":"Tao","family":"Zeng","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Chongqing Innovation Center, Beijing Institute of Technology, Chongqing 401331, China"},{"name":"Yangtze Delta Region Academy of Beijing Institute of Technology, Jiaxing 314019, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6415-1519","authenticated-orcid":false,"given":"Linghao","family":"Li","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Key Laboratory of Embedded Real-Time Information Processing Technology, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,13]]},"reference":[{"key":"ref_1","unstructured":"Carrara, W.G., Goodman, R.S., and Majewski, R.M. 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