{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:59:08Z","timestamp":1760147948998,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,16]],"date-time":"2023-03-16T00:00:00Z","timestamp":1678924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["21-79-10375"],"award-info":[{"award-number":["21-79-10375"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Airborne scatterometer capability depends on not only the device\u2019s technical characteristics but also the scheme used for surface observations. Typically, a rotating-beam scatterometer uses a circular scheme for sampling normalized radar cross-sections (NRCS) at wind measurements over the sea. Here, we investigate wind retrieval using an updated semicircular scheme, providing the NRCS sampling at various combinations of incidence angles within the range 30\u00b0 to 60\u00b0. The effectiveness of the wind retrieval using our semicircular sampling scheme was evaluated using Monte Carlo simulations, and we then developed corresponding wind algorithms that used a geophysical model function (GMF). As a result of the study, we found that a semicircular sampling scheme is well suited for wind retrieval over the sea using a rotating-beam scatterometer. We showed that a semicircular scheme can provide wind retrieval accuracies similar to those achievable with a conventional circular scheme, although the semicircular scheme requires approximately three times the number of NRCS samples integrated in each azimuth sector. Most importantly, however, the semicircular scheme enabled a maximum altitude for wind retrieval of twice the height possible with a circular scheme. In this study, we also demonstrate that the wind speed accuracy tends to increase with an increase in the incidence angle and similarly for the wind direction accuracy. Nonetheless, we then show that the simultaneous use of the NRCS sampling scheme at several incidence angles can increase the wind retrieval accuracy, especially when three or four incidence angles are used. The obtained results can be used to enhance airborne scatterometers and multimode radars operated in a scatterometer mode, including airborne high-altitude conical scanning radars, and can be applied to new remote sensing systems\u2019 development.<\/jats:p>","DOI":"10.3390\/rs15061613","type":"journal-article","created":{"date-parts":[[2023,3,16]],"date-time":"2023-03-16T04:13:20Z","timestamp":1678940000000},"page":"1613","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimization of Airborne Scatterometer NRCS Semicircular Sampling for Sea Wind Retrieval"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4378-1145","authenticated-orcid":false,"given":"Alexey","family":"Nekrasov","sequence":"first","affiliation":[{"name":"Department of Radio Engineering Systems, Saint Petersburg Electrotechnical University, Professora Popova 5F, 197022 Saint Petersburg, Russia"},{"name":"Institute for Computer Technologies and Information Security, Southern Federal University, Chekhova 2, 347922 Taganrog, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5200-5442","authenticated-orcid":false,"given":"Alena","family":"Khachaturian","sequence":"additional","affiliation":[{"name":"Department of Radio Engineering Systems, Saint Petersburg Electrotechnical University, Professora Popova 5F, 197022 Saint Petersburg, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9410-7217","authenticated-orcid":false,"given":"Colin","family":"Fidge","sequence":"additional","affiliation":[{"name":"Faculty of Science, Queensland University of Technology (QUT), Gardens Point Campus, Brisbane, QLD 4001, Australia"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kramer, H.J. 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