{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T07:22:29Z","timestamp":1769844149446,"version":"3.49.0"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T00:00:00Z","timestamp":1613088000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003030","name":"Ag\u00e8ncia de Gesti\u00f3 d'Ajuts Universitaris i de Recerca","doi-asserted-by":"publisher","award":["2020 FISDU 00455"],"award-info":[{"award-number":["2020 FISDU 00455"]}],"id":[{"id":"10.13039\/501100003030","id-type":"DOI","asserted-by":"publisher"}]},{"name":"ARS project","award":["PGC2018-094132-B-I00"],"award-info":[{"award-number":["PGC2018-094132-B-I00"]}]},{"name":"ACTRIS-PPP project","award":["GA-739530"],"award-info":[{"award-number":["GA-739530"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work proposes a new wave-period estimation (L-dB) method based on the power-spectral-density (PSD) estimation of pitch and roll motional time series of a Doppler wind lidar buoy under the assumption of small angles (\u00b122 deg) and slow yaw drifts (1 min), and the neglection of translational motion. We revisit the buoy\u2019s simplified two-degrees-of-freedom (2-DoF) motional model and formulate the PSD associated with the eigenaxis tilt of the lidar buoy, which was modelled as a complex-number random process. From this, we present the L-dB method, which estimates the wave period as the average wavelength associated to the cutoff frequency span at which the spectral components drop off L decibels from the peak level. In the framework of the IJmuiden campaign (North Sea, 29 March\u201317 June 2015), the L-dB method is compared in reference to most common oceanographic wave-period estimation methods by using a TriaxysTM buoy. Parametric analysis showed good agreement (correlation coefficient, \u03c1 = 0.86, root-mean-square error (RMSE) = 0.46 s, and mean difference, MD = 0.02 s) between the proposed L-dB method and the oceanographic zero-crossing method when the threshold L was set at 8 dB.<\/jats:p>","DOI":"10.3390\/s21041310","type":"journal-article","created":{"date-parts":[[2021,2,12]],"date-time":"2021-02-12T18:45:00Z","timestamp":1613155500000},"page":"1310","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Estimation of Wave Period from Pitch and Roll of a Lidar Buoy"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7398-925X","authenticated-orcid":false,"given":"Andreu","family":"Salcedo-Bosch","sequence":"first","affiliation":[{"name":"CommSensLab-UPC, Department of Signal Theory and Communications, Polytechnic University of Catalonia (UPC), C\/ Jordi Girona, 1-3, E-08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8614-4408","authenticated-orcid":false,"given":"Francesc","family":"Rocadenbosch","sequence":"additional","affiliation":[{"name":"CommSensLab-UPC, Department of Signal Theory and Communications, Polytechnic University of Catalonia (UPC), C\/ Jordi Girona, 1-3, E-08034 Barcelona, Spain"},{"name":"Institut d\u2019Estudis Espacials de Catalunya (IEEC), UPC, c\/ Gran Capit\u00e0, 2-4, E-08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3725-3880","authenticated-orcid":false,"given":"Miguel A.","family":"Guti\u00e9rrez-Antu\u00f1ano","sequence":"additional","affiliation":[{"name":"CommSensLab-UPC, Department of Signal Theory and Communications, Polytechnic University of Catalonia (UPC), C\/ Jordi Girona, 1-3, E-08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8359-9378","authenticated-orcid":false,"given":"Jordi","family":"Tiana-Alsina","sequence":"additional","affiliation":[{"name":"Nonlinear Dynamics, Nonlinear Optics and Lasers (DONLL), Department of Physics (DFIS), UPC, C\/ Rambla Sant Nebridi, s\/n, E-08222 Terrassa, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,12]]},"reference":[{"key":"ref_1","unstructured":"Global Wind Energy Council (2019). 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