{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,26]],"date-time":"2025-11-26T16:27:25Z","timestamp":1764174445861,"version":"build-2065373602"},"reference-count":38,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,1,26]],"date-time":"2018-01-26T00:00:00Z","timestamp":1516924800000},"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":["61621005","61671352"],"award-info":[{"award-number":["61621005","61671352"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Innovational Foundation of Shanghai Academy of Space Technology","award":["SAST2016027","SAST2016033"],"award-info":[{"award-number":["SAST2016027","SAST2016033"]}]},{"name":"Key Laboratory of Cognitive Radio and Information Processing, Ministry of Education","award":["CRKL160206"],"award-info":[{"award-number":["CRKL160206"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Circular scanning synthetic aperture radar (SAR) is a novel imaging mode wherein the radar antenna rotates from 0 degrees to 360 degrees along the platform flight direction, providing us with a potentially effective technique to estimate the sea surface current velocity. In this paper, we propose a novel method to estimate the sea surface current velocity utilizing the Doppler centroid shifts of different scan angles over 360 degrees after the airborne platform motion compensation. In this method, the Doppler centroid shifts of the sea clutter at different scan angles are first extracted, and the corresponding compensation errors caused by the azimuth pointing and the incidence angle of the radar beam are considered. Finally, the least squares (LS) technique is applied to estimate the along-track velocity component and the cross-track velocity component of the sea surface current. The effectiveness of the proposed method is verified by the real data recorded by an airborne circular scanning SAR system.<\/jats:p>","DOI":"10.3390\/rs10020178","type":"journal-article","created":{"date-parts":[[2018,1,26]],"date-time":"2018-01-26T11:29:02Z","timestamp":1516966142000},"page":"178","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Sea Surface Current Estimation Using Airborne Circular Scanning SAR with a Medium Grazing Angle"],"prefix":"10.3390","volume":"10","author":[{"given":"Xueli","family":"Pan","sequence":"first","affiliation":[{"name":"National Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guisheng","family":"Liao","sequence":"additional","affiliation":[{"name":"National Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiwei","family":"Yang","sequence":"additional","affiliation":[{"name":"National Laboratory of Radar Signal Processing, Xidian University, Xi\u2019an 710071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hongxing","family":"Dang","sequence":"additional","affiliation":[{"name":"Academy of Space Electronic Information Technology, Xi\u2019an 710100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1016\/j.oceaneng.2015.04.062","article-title":"Effect of ocean currents on ship navigation in the East China Sea","volume":"104","author":"Chen","year":"2015","journal-title":"Ocean Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"368","DOI":"10.1109\/JOE.1985.1145132","article-title":"A model for Doppler peak spectral shift for low grazing angle sea scatter","volume":"10","author":"Trizna","year":"1985","journal-title":"IEEE J. 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