{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T21:17:41Z","timestamp":1768771061515,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,11,27]],"date-time":"2019-11-27T00:00:00Z","timestamp":1574812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The National Key Research and Development Plan","award":["2017YFF0206404"],"award-info":[{"award-number":["2017YFF0206404"]}]},{"name":"The National Key Research and Development Plan","award":["2016YFC1400504"],"award-info":[{"award-number":["2016YFC1400504"]}]},{"DOI":"10.13039\/501100001809","name":"The National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41506201"],"award-info":[{"award-number":["41506201"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"The National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41376182"],"award-info":[{"award-number":["41376182"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Public Science and Technology Research Funds Projects of Ocean","award":["201205032"],"award-info":[{"award-number":["201205032"]}]},{"name":"The Project of Hubei Province Science and Technology Support Program","award":["2014BEC057"],"award-info":[{"award-number":["2014BEC057"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>To expand the scope of ocean wave observations, a shipboard coherent S-band wave radar system was developed recently. The radar directly measures the wave orbital velocity from the Doppler shift of the received radar signal. The sources of this Doppler shift are analyzed. After removing the Doppler shifts caused by the ocean current and platform, the radial velocities of water particles of the surface gravity waves are retrieved. Subsequently, the wavenumber spectrum can be obtained based on linear wave theory. Later, the significant wave height and wave periods (including mean wave period and peak wave period) can be calculated from the wavenumber spectrum. This radar provides a calibration-free way to measure wave parameters and is a novel underway coherent microwave wave radar. From 9 September to 11 September 2018, an experiment involving radar-derived and buoy-measured wave measurements was conducted in the South China Sea. The Doppler spectra obtained when the ship was in the state of navigation or mooring indicated that the quality of the radar echo was fairly good. The significant wave heights and wave periods measured using the radar are compared with those obtained from the wave buoy. The correlation coefficients of wave heights and mean wave periods between these two instruments both exceed 0.9 while the root mean square differences are respectively less than 0.15 m and 0.25 s, regardless of the state of motion of the ship. These results indicate that this radar has the capability to accurately measure ocean wave heights and wave periods.<\/jats:p>","DOI":"10.3390\/rs11232812","type":"journal-article","created":{"date-parts":[[2019,11,28]],"date-time":"2019-11-28T08:14:04Z","timestamp":1574928844000},"page":"2812","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Wave Height and Wave Period Derived from a Shipboard Coherent S-Band Wave Radar in the South China Sea"],"prefix":"10.3390","volume":"11","author":[{"given":"Zezong","family":"Chen","sequence":"first","affiliation":[{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"},{"name":"School of Electronic Information and the Collaborative Innovation Center for Geospatial Technology, Wuhan University, Wuhan 430072, China"}]},{"given":"Xi","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8335-3749","authenticated-orcid":false,"given":"Chen","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Zihan","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Electronic Information, Wuhan University, Wuhan 430072, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Barrick, D. (1972, January 13\u201315). Remote sensing of sea state by radar. Proceedings of the Ocean 72\u2014IEEE International Conference on Engineering in the Ocean Environment, Newport, RI, USA.","DOI":"10.1109\/OCEANS.1972.1161190"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5926","DOI":"10.1109\/TGRS.2015.2427748","article-title":"Comparison of Incoherent and Coherent Wave Field Measurements Using Dual-Polarized Pulse-Doppler X-Band Radar","volume":"53","author":"Hackett","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"999","DOI":"10.1007\/s10236-014-0725-6","article-title":"Marine radar ocean wave retrieval\u2019s dependency on range and azimuth","volume":"64","author":"Lund","year":"2014","journal-title":"Ocean Dynam."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"676","DOI":"10.1175\/1520-0426(1997)014<0676:MOOSCF>2.0.CO;2","article-title":"Measurements of Ocean Surface Currents from a Moving Ship Using VHF Radar","volume":"14","author":"Peters","year":"1997","journal-title":"J. Atmos. Oceanic Technol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"457","DOI":"10.3389\/fmars.2018.00457","article-title":"Air-Sea CO2 Exchange in a Large Annular Wind-Wave Tank and the Effects of Surfactants","volume":"5","author":"Mariana","year":"2018","journal-title":"Front. Mar. Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1928","DOI":"10.1175\/JTECH-D-14-00175.1","article-title":"On Shipboard Marine X-Band Radar Near-Surface Current \u201cCalibration\u201d","volume":"32","author":"Lund","year":"2015","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1029\/JC090iC01p01049","article-title":"A three-dimensional analysis of marine radar images for the determination of ocean wave directionality and surface currents","volume":"90","author":"Young","year":"1985","journal-title":"J. Geophys. Res."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Trizna, D.B. (2009, January 26\u201329). Coherent microwave marine radar measurements of directional ocean wave spectra and mean radial current fields. Proceedings of the OCEANS 2009, Biloxi, MS, USA.","DOI":"10.23919\/OCEANS.2009.5422287"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1542","DOI":"10.1587\/elex.9.1542","article-title":"Ocean wave directional spectrum measurement using microwave coherent radar with six antennas","volume":"9","author":"Chen","year":"2012","journal-title":"IEICE Electron. Express"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Chen, Z.Z., Wang, Z.H., Chen, X., Zhao, C., Xie, F., and He, C. (2017). S-Band Doppler Wave Radar System. Remote Sens., 9.","DOI":"10.3390\/rs9121302"},{"key":"ref_11","unstructured":"Johan, A.O. (2005). On Mixed Wind-Sea\/Swell Conditions in the Open Ocean: Model and Radar-Observations. [Master\u2019s Thesis, The University of Bergen]."},{"key":"ref_12","unstructured":"Catalan Mondaca, P.A. (2008). Microwave Scattering from Surf Zone Waves. [Ph.D. Thesis, Oregon State University]."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"9705","DOI":"10.1029\/93JC00862","article-title":"The dependence of microwave backscatter from the sea on illuminated area: Correlation times and lengths","volume":"99","author":"Plant","year":"1994","journal-title":"J. Geophys. Res."},{"key":"ref_14","unstructured":"Flampouris, S. (2007). On the Wave Field Propagating over an Uneven Sea Bottom Observed by Ground Based Radar. [Ph.D. Thesis, Vom Department Geowissenschaften der Universitat Hamburg als Dissertation angenommene Arbeit]."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Trizna, D.B. (2016, January 10\u201313). Coherent marine radar measurements of ocean wave frequency spectra and near surface currents. Proceedings of the OCEANS 2016, Shanghai, China.","DOI":"10.1109\/OCEANSAP.2016.7485714"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"73","DOI":"10.5957\/jsr.2011.55.2.73","article-title":"Ship Motion and Wave Radar Data Fusion for Shipboard Wave Measurement","volume":"55","author":"Stredulinsky","year":"2011","journal-title":"J. Ship. Res."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Ho, D.T., Sabine, C.L., Hebert, D., Ullman, D.S., and Hargreaves, B.R. (2011). Southern Ocean Gas Exchange Experiment: Setting the stage. J. Geophys. Res., 116.","DOI":"10.1029\/2010JC006852"},{"key":"ref_18","first-page":"248","article-title":"Real time local sea state measurement using wave radar and ship motions","volume":"118","author":"Thornhill","year":"2010","journal-title":"Trans. Soc. Nav. Archit. Mar. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2907","DOI":"10.1175\/JTECH-D-12-00181.1","article-title":"A Multisensor Comparison of Ocean Wave Frequency Spectra from a Research Vessel during the Southern Ocean Gas Exchange Experiment","volume":"30","author":"Edson","year":"2013","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3373","DOI":"10.1109\/TGRS.2013.2272701","article-title":"An Algorithm for Estimation of Wave Height From Shadowing in X-Band Radar Sea Surface Images","volume":"52","author":"Gangeskar","year":"2014","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Ludeno, G., Orlandi, A., Lugni, C., Brandini, C., Soldovieri, F., and Serafino, F. (2013). X-band marine radar system for high speed navigation purposes: A test case on a cruise ship. IEEE Geosci. Remote Sens. Lett.","DOI":"10.1109\/LGRS.2013.2254464"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.3390\/s110101009","article-title":"A Simple Strategy to Mitigate the Aliasing Effect in X-band Marine Radar Data: Numerical Results for a 2D Case","volume":"11","author":"Serafino","year":"2011","journal-title":"Sensors"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"973","DOI":"10.1007\/s10236-016-0961-z","article-title":"Multi-directional wave spectra from marine X-band radar","volume":"66","author":"Lund","year":"2016","journal-title":"Ocean Dyn."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2113","DOI":"10.1175\/JTECH-D-16-0212.1","article-title":"Shipboard Wave Measurements in the Southern Ocean","volume":"34","author":"Lund","year":"2017","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Huang, W., Liu, X., and Gill, E.W. (2017). Ocean Wind and Wave Measurements Using X-Band Marine Radar: A Comprehensive Review. Remote Sens., 9.","DOI":"10.3390\/rs9121261"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"95","DOI":"10.5194\/os-13-95-2017","article-title":"A simple method for retrieving significant wave height from Dopplerized X-band radar","volume":"13","author":"Carrasco","year":"2017","journal-title":"Ocean Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1404","DOI":"10.1016\/j.oceaneng.2004.11.005","article-title":"Analysis of sea waves and wind from X-band radar","volume":"32","author":"Izquierdo","year":"2005","journal-title":"Ocean Eng."},{"key":"ref_28","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. Geosci. Remote Sens."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"443","DOI":"10.1007\/BF02675917","article-title":"On the problem of the Doppler spectrum of a microwave radar signal backscattered by the sea surface (transition region and bragg component)","volume":"40","author":"Karaev","year":"1997","journal-title":"Radiophys. Quantum Electron."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"16299","DOI":"10.1029\/JC095iC09p16299","article-title":"Evidence of Bragg scattering in microwave Doppler spectra of sea return","volume":"95","author":"Plant","year":"1990","journal-title":"J. Geophys. Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"811","DOI":"10.1109\/36.158877","article-title":"A backscattering model for ocean surface","volume":"30","author":"Chen","year":"1991","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1017\/S0022112063001452","article-title":"The effect of non-linearities on statistical distributions in the theory of sea waves","volume":"17","year":"1963","journal-title":"J. Fluid. Mech."},{"key":"ref_33","unstructured":"Gurgel, K.W. (1994, January 13\u201316). Shipborne measurement of surface current fields by HF radar. Proceedings of the OCEANS\u201994, Brest, France."},{"key":"ref_34","unstructured":"Love, L.J., Jansen, J.F., and Pin, F.G. (May, January 26). On the modeling of robots operating on ships. Proceedings of the ICRA\u201904\u2014New Orleans, New Orleans, LA, USA."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1049\/ip-rsn:19982220","article-title":"Time-varying spectral analysis for radar imaging of manoeuvring targets","volume":"145","author":"Chen","year":"1998","journal-title":"IEE P-Radar. Son. Nav."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1109\/TAES.2006.1603402","article-title":"Micro-Doppler effect in radar: Phenomenon, model, and simulation study","volume":"42","author":"Chen","year":"2006","journal-title":"IEEE Trans. Aerosp. Electron. Syst."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1271","DOI":"10.1175\/1520-0426(1995)012<1271:SBFRMO>2.0.CO;2","article-title":"S-Band FMCW Radar Measurements of Ocean Surface Dynamics","volume":"12","author":"Poulter","year":"1995","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"12839","DOI":"10.1029\/98JC00781","article-title":"Radar-derived interferometric surface currents and their relationship to subsurface current structure","volume":"103","author":"Moller","year":"1998","journal-title":"J. Geophys. Res."},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Plant, W.J. (2002). A stochastic, multiscale model of microwave backscatter from the ocean. J. Geophys. Res., 107.","DOI":"10.1029\/2001JC000909"},{"key":"ref_40","first-page":"2382","article-title":"The Ocean Wave Height Variance Spectrum: Wavenumber Peak versus Frequency Peak","volume":"39","author":"Plant","year":"2009","journal-title":"J. Geophys. Res."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1098\/rsta.1985.0054","article-title":"Directional Spectra of Wind-Generated Waves","volume":"315","author":"Donelan","year":"1985","journal-title":"Philos. Trans. R. Soc. Lond. Ser. A"},{"key":"ref_42","unstructured":"Michael, E.M. (2009). Ocean Engineering Mechanic: With Applications, Cambridge University Press. [1st ed.]."},{"key":"ref_43","first-page":"5332","article-title":"Estimation of Significant Wave Height Using Satellite Data","volume":"4","author":"Sathiya","year":"2012","journal-title":"Res. J. Appl. Sci. Eng. Technol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"7929","DOI":"10.1029\/93JC03562","article-title":"Microwave backscatter from the sea surface: Bragg scattering by short gravity waves","volume":"99","author":"Poulter","year":"1994","journal-title":"J. Geophys. Res."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"805","DOI":"10.1109\/36.752196","article-title":"A Method of Spectral Moment Estimation","volume":"37","author":"Monakov","year":"1999","journal-title":"IEEE Trans. Geosci. Remote Sens."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/23\/2812\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:38:06Z","timestamp":1760189886000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/23\/2812"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,27]]},"references-count":45,"journal-issue":{"issue":"23","published-online":{"date-parts":[[2019,12]]}},"alternative-id":["rs11232812"],"URL":"https:\/\/doi.org\/10.3390\/rs11232812","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,11,27]]}}}