{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T09:35:37Z","timestamp":1770543337822,"version":"3.49.0"},"reference-count":49,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,10,9]],"date-time":"2023-10-09T00:00:00Z","timestamp":1696809600000},"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":["41976167"],"award-info":[{"award-number":["41976167"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["42376176"],"award-info":[{"award-number":["42376176"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The Doppler characteristics of sea surface echoes reflect the time-varying characteristics of the sea surface and can be used to retrieve ocean dynamic parameters and detect targets. On airborne, spaceborne and shipborne radar platforms, radar moves along with the platforms while illuminating the sea surface. In this case, the area of the sea surface illuminated by radar beam changes rapidly with the motion, and the coherence of the backscattered echoes at different times decreases significantly. Therefore, the Doppler characteristics of the echoes would also be affected by the radar motion. At present, the computational requirements needed to simulate the Doppler spectrum of the microwave scattering field from the sea surface based on numerical methods are huge. To overcome this problem, a new method based on the sub-scattering surface elements has been proposed to simulate the Doppler spectrum of sea echoes acquired by a moving microwave radar. A comparison with the results evaluated by the SSA demonstrate the availability and superiority of the new method proposed by us. The influences induced by radar motion, radar beamwidth, incident angle, and thermal noise on the Doppler characteristics are all considered in this new method. The simulated results demonstrate that the spectrum bandwidth of sea surface echoes acquired by radar on the dive staring motion platform becomes somewhat narrower.<\/jats:p>","DOI":"10.3390\/rs15194888","type":"journal-article","created":{"date-parts":[[2023,10,9]],"date-time":"2023-10-09T10:48:33Z","timestamp":1696848513000},"page":"4888","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["The Doppler Characteristics of Sea Echoes Acquired by Motion Radar"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-5306-5947","authenticated-orcid":false,"given":"Pengbo","family":"Du","sequence":"first","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"},{"name":"National Key Laboratory of Electromagnetic Environment, China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4770-3753","authenticated-orcid":false,"given":"Yunhua","family":"Wang","sequence":"additional","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"},{"name":"Laboratory for Regional Oceanography and Numerical Modeling, Laoshan Laboratory, Qingdao 266237, China"}]},{"given":"Xin","family":"Li","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Electromagnetic Environment, China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]},{"given":"Jianbo","family":"Cui","sequence":"additional","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7337-9467","authenticated-orcid":false,"given":"Yanmin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"}]},{"given":"Qian","family":"Li","sequence":"additional","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"}]},{"given":"Yushi","family":"Zhang","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Electromagnetic Environment, China Research Institute of Radiowave Propagation, Qingdao 266107, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,10,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"07008","DOI":"10.1029\/2004JC002809","article-title":"Direct measurements of ocean surface velocity from space: Interpretation and validation","volume":"110","author":"Chapron","year":"2005","journal-title":"J. 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