{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T12:18:14Z","timestamp":1764937094002,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,6,20]],"date-time":"2019-06-20T00:00:00Z","timestamp":1560988800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012164","name":"National High-tech Research and Development Program","doi-asserted-by":"publisher","award":["Grant SS2013aa120602"],"award-info":[{"award-number":["Grant SS2013aa120602"]}],"id":[{"id":"10.13039\/501100012164","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Science Foundation of China","doi-asserted-by":"publisher","award":["61171070"],"award-info":[{"award-number":["61171070"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The Global Navigation Satellite System Reflectometry (GNSS-R) technique exploits the characteristics of reflected GNSS signals to estimate the geophysical parameters of the earth\u2019s surface. This paper focuses on investigating the wind speed retrieval method using ocean scattered signals from a Beidou Geostationary Earth Orbit (GEO) satellite. Two new observables are proposed by computing the ratio of the low energy zone and the high energy zone of the delay waveform. Coastal experimental raw data from a Beidou GEO satellite are processed to establish the relationship between the energy-related observables and the sea surface wind. When the delay waveform normalized amplitude (this will be referred to as \u201cthreshold\u201d in what follows) is 0.3, fitting results show that the coefficient of determination is more than 0.76 in the gentle wind scenario (&lt;10 m\/s), with a root mean square error (RMSE) of less than 1.0 m\/s. In the Typhoon UTOR scenario (12.7 m\/s~37.3 m\/s), the correlation level exceeds 0.82 when the threshold is 0.25, with a RMSE of less than 3.10 m\/s. Finally, the impact of the threshold and coherent integration time on wind speed retrieval is discussed to obtain an optimal result. When the coherent integration time is 50 milliseconds and the threshold is 0.15, the best wind speed retrieval error of 2.63 m\/s and a correlation level of 0.871 are obtained in the UTOR scenario.<\/jats:p>","DOI":"10.3390\/s19122779","type":"journal-article","created":{"date-parts":[[2019,6,20]],"date-time":"2019-06-20T10:49:59Z","timestamp":1561027799000},"page":"2779","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["A Novel Method for Ocean Wind Speed Detection Based on Energy Distribution of Beidou Reflections"],"prefix":"10.3390","volume":"19","author":[{"given":"Qiang","family":"Wang","sequence":"first","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunlong","family":"Zhu","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0423-9823","authenticated-orcid":false,"given":"Kittipong","family":"Kasantikul","sequence":"additional","affiliation":[{"name":"School of Electronic and Information Engineering, Beihang University (BUAA), Beijing 100191, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,20]]},"reference":[{"key":"ref_1","first-page":"331","article-title":"A pasive reflectometry and interferometry system (paris) application to ocean altimetry","volume":"17","year":"1993","journal-title":"Esa J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1375","DOI":"10.1029\/2002GL014759","article-title":"5-cm-Precision aircraft ocean altimetry using GPS reflections","volume":"29","author":"Lowe","year":"2002","journal-title":"Geophys. 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