{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T21:28:09Z","timestamp":1772054889090,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2015,8,7]],"date-time":"2015-08-07T00:00:00Z","timestamp":1438905600000},"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":["No. 41274017"],"award-info":[{"award-number":["No. 41274017"]}],"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":["No. 40974001"],"award-info":[{"award-number":["No. 40974001"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Monitoring ocean waves plays a crucial role in, for example, coastal environmental and protection studies. Traditional methods for measuring ocean waves are based on ultrasonic sensors and accelerometers. However, the Global Positioning System (GPS) has been introduced recently and has the advantage of being smaller, less expensive, and not requiring calibration in comparison with the traditional methods. Therefore, for accurately measuring ocean waves using GPS, further research on the separation of the wave signals from the vertical GPS-mounted carrier displacements is still necessary. In order to contribute to this topic, we present a novel method that combines complementary ensemble empirical mode decomposition (CEEMD) with a wavelet threshold denoising model (i.e., CEEMD-Wavelet). This method seeks to extract wave signals with less residual noise and without losing useful information. Compared with the wave parameters derived from the moving average skill, high pass filter and wave gauge, the results show that the accuracy of the wave parameters for the proposed method was improved with errors of about 2 cm and 0.2 s for mean wave height and mean period, respectively, verifying the validity of the proposed method.<\/jats:p>","DOI":"10.3390\/s150819416","type":"journal-article","created":{"date-parts":[[2015,8,7]],"date-time":"2015-08-07T10:25:21Z","timestamp":1438943121000},"page":"19416-19428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Ocean Wave Separation Using CEEMD-Wavelet in GPS  Wave Measurement"],"prefix":"10.3390","volume":"15","author":[{"given":"Junjie","family":"Wang","sequence":"first","affiliation":[{"name":"School of Earth Science and Engineering, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiufeng","family":"He","sequence":"additional","affiliation":[{"name":"School of Earth Science and Engineering, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2209-9921","authenticated-orcid":false,"given":"Vagner","family":"Ferreira","sequence":"additional","affiliation":[{"name":"School of Earth Science and Engineering, Hohai University, Nanjing 210098, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,8,7]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"An overview of recent technologies on wave and current measurement in coastal and marine applications","volume":"1","author":"Pitchai","year":"2010","journal-title":"J. Oceanogr. Mar. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1043","DOI":"10.3390\/s110101043","article-title":"Wave measurements using gps velocity signals","volume":"11","author":"Doong","year":"2011","journal-title":"Sensors"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"944","DOI":"10.1175\/JTECH-D-11-00128.1","article-title":"Observing ocean surface waves with gps-tracked buoys","volume":"29","author":"Herbers","year":"2012","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1016\/S0378-3839(99)00031-9","article-title":"Some recent developments in wave buoy measurement technology","volume":"37","author":"Krogstad","year":"1999","journal-title":"Coast. Eng."},{"key":"ref_5","unstructured":"Yoo, Y., Hou, D., Kouguchi, N., Ishida, H., Shiotani, S., Fujii, H., and Deguchi, I. (2004, January 9\u201312). Arrayed gps-buoys wave observation system. Proceedings of the OCEANS\u201904 Marine Technology Society (MTS)\/IEEE TECHNO-OCEAN\u201904, Kobe, Japan."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Nagai, T., Shimizu, K., Sasaki, M., and Murakami, A. (2008, January 8\u201311). Characteristics of the observed offshore wave data by the gps buoys. Proceedings of the OCEANS 2008 Marine Technology Society (MTS)\/IEEE Kobe Techno-Ocean, Kobe, Japan.","DOI":"10.1109\/OCEANSKOBE.2008.4530938"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"269","DOI":"10.5047\/eps.2009.11.006","article-title":"Empirical relationship of tsunami height between offshore and coastal stations","volume":"62","author":"Hayashi","year":"2010","journal-title":"Earth Planets Sp."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1061\/(ASCE)WW.1943-5460.0000235","article-title":"2010 chile and 2011 tohoku tsunami profiles measured by gps buoys and coastal wave and tide gauges in a nationwide ocean wave information network for ports and harbors","volume":"140","author":"Kawai","year":"2014","journal-title":"J. Waterw. Port Coast.Ocean Eng."},{"key":"ref_9","first-page":"50","article-title":"Field tests of the new datawell  DWR-G GPS wave buoy","volume":"44","author":"Waldron","year":"2003","journal-title":"Sea Technol."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Hou, D., Hamada, M., Yoo, Y.-J., and Kouguchi, N. (2006, January 16\u201319). Evaluation test result on wave direction measurement using gps buoy. Proceedings of the OCEANS'06 Asia Pacific IEEE, Singapore.","DOI":"10.1109\/OCEANSAP.2006.4393875"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Akiyoshi, G., and Kouguchi, N. (2012, January 21\u201324). Wave information by precise velocity measurement using gps buoy. Proceedings of the OCEANS 2012 Marine Technology Society (MTS)\/IEEE Yeosu, Yeosu, Korea.","DOI":"10.1109\/OCEANS-Yeosu.2012.6263444"},{"key":"ref_12","first-page":"45","article-title":"Inter-comparison of wave measurement by accelerometer and GPS wave buoy in shallow water off cuddalore, east coast of india","volume":"43","author":"Patra","year":"2014","journal-title":"Indian J. Geo Mar. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1760","DOI":"10.1175\/2010JTECHO761.1","article-title":"Wave heights during hurricane katrina: An evaluation of PPP and PPK measurements of the vertical displacement of the GPS antenna","volume":"27","author":"Bender","year":"2010","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"163","DOI":"10.2478\/jogs-2013-0023","article-title":"Ocean wave measurement using GPS buoys","volume":"3","author":"Joodaki","year":"2013","journal-title":"J. Geod. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"903","DOI":"10.1098\/rspa.1998.0193","article-title":"The empirical mode decomposition and the hilbert spectrum for nonlinear and non-stationary time series analysis","volume":"454","author":"Huang","year":"1998","journal-title":"Proc. R. Soc. A Math. Phys. Eng. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"112","DOI":"10.1109\/LSP.2003.821662","article-title":"Empirical mode decomposition as a filter bank","volume":"11","author":"Flandrin","year":"2004","journal-title":"IEEE Signal Process. Lett."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1597","DOI":"10.1098\/rspa.2003.1221","article-title":"A study of the characteristics of white noise using the empirical mode decomposition method","volume":"460","author":"Wu","year":"2004","journal-title":"Proc. R. Soc. A Math. Phys. Eng. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1142\/S1793536909000047","article-title":"Ensemble empirical mode decomposition: A noise-assisted data analysis method","volume":"1","author":"Wu","year":"2009","journal-title":"Adv. Adapt. Data Anal."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1142\/S1793536910000422","article-title":"Complementary ensemble empirical mode decomposition: A novel noise enhanced data analysis method","volume":"2","author":"Yeh","year":"2010","journal-title":"Adv. Adapt. Data Anal."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Torres, M.E., Colominas, M.A., Schlotthauer, G., and Flandrin, P. (2011, January 22\u201327). A complete ensemble empirical mode decomposition with adaptive noise. Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, Prague, Czech.","DOI":"10.1109\/ICASSP.2011.5947265"},{"key":"ref_21","unstructured":"Datawell > Products > Buoys. Available online: http:\/\/www.datawell.nl\/Products\/Buoys.aspx."},{"key":"ref_22","unstructured":"Shan, R. (2010). Study of Sea Wave and Tide Measurements Based on GPS Velocity Estimation. [Master\u2019s Thesis, Shandong University of Science and Technolog]. (In Chinese)."},{"key":"ref_23","unstructured":"Herring, T., King, R., and McClusky, S. (2010). GAMIT\/GLOBK Reference Manuals, Release 10.4, Massachusetts Institute of Technology."},{"key":"ref_24","first-page":"773","article-title":"High-rate (1 Hz to 20 Hz) gps coseismic dynamic displacements carried out during the emilia 2012 seismic sequence","volume":"55","author":"Avallone","year":"2012","journal-title":"Ann. Geophys."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1007\/s00190-010-0371-9","article-title":"Single receiver phase ambiguity resolution with GPS data","volume":"84","author":"Bertiger","year":"2010","journal-title":"J. Geod."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/8\/19416\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:50:21Z","timestamp":1760215821000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/15\/8\/19416"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,8,7]]},"references-count":25,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2015,8]]}},"alternative-id":["s150819416"],"URL":"https:\/\/doi.org\/10.3390\/s150819416","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,8,7]]}}}