{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T02:24:52Z","timestamp":1769826292962,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,12,2]],"date-time":"2023-12-02T00:00:00Z","timestamp":1701475200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation project","award":["U22A20243"],"award-info":[{"award-number":["U22A20243"]}]},{"name":"National Natural Science Foundation project","award":["52125106"],"award-info":[{"award-number":["52125106"]}]},{"name":"National Natural Science Foundation project","award":["41976167"],"award-info":[{"award-number":["41976167"]}]},{"name":"National Natural Science Foundation project","award":["LSKJ202201302"],"award-info":[{"award-number":["LSKJ202201302"]}]},{"name":"National Outstanding Youth Science Fund Project of the National Natural Science Foundation of China","award":["U22A20243"],"award-info":[{"award-number":["U22A20243"]}]},{"name":"National Outstanding Youth Science Fund Project of the National Natural Science Foundation of China","award":["52125106"],"award-info":[{"award-number":["52125106"]}]},{"name":"National Outstanding Youth Science Fund Project of the National Natural Science Foundation of China","award":["41976167"],"award-info":[{"award-number":["41976167"]}]},{"name":"National Outstanding Youth Science Fund Project of the National Natural Science Foundation of China","award":["LSKJ202201302"],"award-info":[{"award-number":["LSKJ202201302"]}]},{"name":"National Natural Science Foundation of China","award":["U22A20243"],"award-info":[{"award-number":["U22A20243"]}]},{"name":"National Natural Science Foundation of China","award":["52125106"],"award-info":[{"award-number":["52125106"]}]},{"name":"National Natural Science Foundation of China","award":["41976167"],"award-info":[{"award-number":["41976167"]}]},{"name":"National Natural Science Foundation of China","award":["LSKJ202201302"],"award-info":[{"award-number":["LSKJ202201302"]}]},{"name":"Laoshan Laboratory Science and Technology Innovation Projects","award":["U22A20243"],"award-info":[{"award-number":["U22A20243"]}]},{"name":"Laoshan Laboratory Science and Technology Innovation Projects","award":["52125106"],"award-info":[{"award-number":["52125106"]}]},{"name":"Laoshan Laboratory Science and Technology Innovation Projects","award":["41976167"],"award-info":[{"award-number":["41976167"]}]},{"name":"Laoshan Laboratory Science and Technology Innovation Projects","award":["LSKJ202201302"],"award-info":[{"award-number":["LSKJ202201302"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The feasibility of using millimeter-wave radars for wave observations was investigated in this study. The radars used in this study operate at a center frequency of 77.572 GHz. To investigate the feasibility of wave observations and extract one-dimensional and two-dimensional wave spectra, arrays consisting of multiple radar units were deployed for observations in both laboratory and field environments. Based on the data measured with the millimeter-wave radars, one-dimensional wave spectra and two-dimensional wave directional spectra were evaluated using the periodogram method and the Bayesian directional spectrum estimation method (BDM), respectively. Meanwhile, wave parameters such as the significant wave height, wave period, and wave direction were also calculated. Via comparative experiments with a capacitive wave height meter in a wave tank and RADAC\u2019s WG5-HT-CP radar in an offshore field, the viability of using millimeter-wave radars to observe water waves was validated. The results indicate that the one-dimensional wave spectra measured with the millimeter-wave radars were consistent with those measured with the mature commercial capacitive wave height meter and the WG5-HT-CP wave radar. Via wave direction measurement experiments conducted in a wave tank and offshore environment, it is evident that the wave directions retrieved with the millimeter-wave radars were in good alignment with the actual wave directions.<\/jats:p>","DOI":"10.3390\/rs15235606","type":"journal-article","created":{"date-parts":[[2023,12,2]],"date-time":"2023-12-02T13:45:41Z","timestamp":1701524741000},"page":"5606","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Investigation on the Utilization of Millimeter-Wave Radars for Ocean Wave Monitoring"],"prefix":"10.3390","volume":"15","author":[{"given":"Xindi","family":"Liu","sequence":"first","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, 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":"The Laboratory for Regional Oceanography and Numerical Modeling, Laoshan Laboratory, Qingdao 266237, China"}]},{"given":"Fushun","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Engineering, Ocean University of China, Qingdao 266100, China"}]},{"given":"Yuting","family":"Zhang","sequence":"additional","affiliation":[{"name":"Faculty of Information Science and Engineering, Ocean University of China, Qingdao 266100, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5355","DOI":"10.1109\/TGRS.2017.2706067","article-title":"Significant wave height measured by coherent X-band radar","volume":"55","author":"Carrasco","year":"2017","journal-title":"IEEE Trans. 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