{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T14:25:25Z","timestamp":1775744725029,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,17]],"date-time":"2022-11-17T00:00:00Z","timestamp":1668643200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The monitoring of ships is of paramount importance for ocean and coastal area surveillance. The synthetic aperture radar is shown to be a key sensor to provide effective and continuous observation of ships due to its unique imaging capabilities. When advanced synthetic aperture radar imaging systems are considered, the full scattering information is available that was demonstrated to be beneficial in developing improved ship detection and classification algorithms. Nonetheless, the capability of polarimetric synthetic aperture radar to observe marine vessels is significantly affected by several imaging and environmental parameters, including the incidence angle. Nonetheless, how changes in the incidence angle affect the scattering of ships still needs to be further investigated since only a sparse analysis, i.e., on different kinds of ships of different sizes observed at multiple incidence angles, has been performed. Hence, in this study, for the first time, the polarimetric scattering of the same ship, i.e., a small fishing trawler, which is imaged multiple times under the same sea state conditions but in a wide range of incidence angles, is analysed. This unique opportunity is provided by a premium L-band UAVSAR airborne dataset that consists of five full-polarimetric synthetic aperture radar scenes collected in the Gulf of Mexico. Experimental results highlight the key role played by the incidence angle on both coherent, i.e., co-polarisation signature and pedestal height, and incoherent, i.e., multi-polarisation and total backscattering power, polarimetric scattering descriptors. Experimental results show that: (1) the polarised scattering component is more sensitive to the incidence angle with respect to the unpolarised one; (2) the co-polarised channel under horizontal polarisation dominated the polarimetric backscattering from the fishing trawler at lower angles of incidence, while both co-polarised channels contribute to the polarimetric backscattering at higher incidence angles; (3) the HV polarisation provides the largest target-to-clutter ratio at lower incidence angles, while the HH polarisation should be preferred at higher angles of incidence.<\/jats:p>","DOI":"10.3390\/rs14225813","type":"journal-article","created":{"date-parts":[[2022,11,18]],"date-time":"2022-11-18T04:08:40Z","timestamp":1668744520000},"page":"5813","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["On the Effects of the Incidence Angle on the L-Band Multi-Polarisation Scattering of a Small Ship"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1042-4507","authenticated-orcid":false,"given":"Muhammad","family":"Adil","sequence":"first","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5523-7609","authenticated-orcid":false,"given":"Andrea","family":"Buono","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4567-0377","authenticated-orcid":false,"given":"Ferdinando","family":"Nunziata","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0421-6477","authenticated-orcid":false,"given":"Emanuele","family":"Ferrentino","sequence":"additional","affiliation":[{"name":"Sezione Osservazione della Terra, Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8592-0652","authenticated-orcid":false,"given":"Domenico","family":"Velotto","sequence":"additional","affiliation":[{"name":"Center for Environmental Sciences, University of Bremen, Leobener Strasse 8, 28359 Bremen, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8363-3502","authenticated-orcid":false,"given":"Maurizio","family":"Migliaccio","sequence":"additional","affiliation":[{"name":"Dipartimento di Ingegneria, Universit\u00e0 degli Studi di Napoli Parthenope, Centro Direzionale isola C4, 80143 Naples, Italy"},{"name":"Sezione Osservazione della Terra, Istituto Nazionale di Geofisica e Vulcanologia, Via di Vigna Murata 605, 00143 Rome, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,17]]},"reference":[{"key":"ref_1","unstructured":"(2022, July 28). CLEANSEANET Service European Maritime Safety Agency (EMSA). Available online: http:\/\/cleanseanet.emsa.europa.eu\/."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Curlander, J.C., and McDonough, R.N. (1991). Synthetic Aperture Radar, Wiley.","DOI":"10.1016\/0045-8732(91)90094-O"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2725","DOI":"10.1109\/TGRS.2003.817809","article-title":"On the use of complex SAR image spectral analysis for target detection: Assessment of polarimetry","volume":"41","author":"Souyris","year":"2003","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"893","DOI":"10.1109\/JSTARS.2012.2184271","article-title":"Single-look complex COSMO-SkyMed SAR data to observe metallic targets at sea","volume":"5","author":"Migliaccio","year":"2012","journal-title":"IEEE J. Selected Topics Appl. Earth Obs. Remote Sens."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1212","DOI":"10.1109\/TGRS.2008.2008443","article-title":"Phenomenological vessel scattering study based on simulated inverse SAR imagery","volume":"47","author":"Margarit","year":"2009","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_6","unstructured":"Stefanowicz, J., Ali, I., and Andersson, S. (September, January 31). Current trends in ship detection in single polarization synthetic aperture radar imagery. Proceedings of the Photonics Applications in Astronomy, Communications, Industry, and High Energy Physics Experiments 2020, Wilga, Poland."},{"key":"ref_7","unstructured":"Crisp, D.J. (2004). The State-of-the-Art in Ship Detection in Synthetic Aperture Radar Imagery, Defence Science And Technology Organisation Salisbury. Technical report."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1109\/TGRS.2019.2931353","article-title":"CFAR ship detection in polarimetric synthetic aperture radar images based on whitening filter","volume":"58","author":"Liu","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"723","DOI":"10.1109\/LGRS.2009.2024224","article-title":"Ship detection using polarization cross-entropy","volume":"6","author":"Chen","year":"2009","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4729","DOI":"10.1109\/TGRS.2011.2158828","article-title":"A multifrequency polarimetric SAR processing chain to observe oil fields in the Gulf of Mexico","volume":"49","author":"Migliaccio","year":"2011","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1109\/JOE.2011.2109491","article-title":"GK-based observation of metallic targets at sea in full-resolution SAR data: A multipolarization study","volume":"36","author":"Ferrara","year":"2011","journal-title":"IEEE J. Ocean. Eng"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.1109\/JSTARS.2013.2247741","article-title":"A notch filter for ship detection with polarimetric SAR data","volume":"6","author":"Marino","year":"2013","journal-title":"IEEE J. Selected Topics Appl. Earth Obs. Remote Sens."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"8225","DOI":"10.1109\/TGRS.2020.2989425","article-title":"PolSAR ship detection using the joint polarimetric information","volume":"58","author":"Zhang","year":"2020","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Iervolino, P., Guida, R., Lumsdon, P., Janoth, J., Clift, M., Minchella, A., and Bianco, P. (2017, January 23\u201328). Ship detection in SAR imagery: A comparison study. Proceedings of the 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, TX, USA.","DOI":"10.1109\/IGARSS.2017.8127384"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3760","DOI":"10.1109\/JSTARS.2014.2359141","article-title":"The Extended Bragg Scattering Model-Based Method for Ship and Oil-Spill Observation Using Compact Polarimetric SAR","volume":"8","author":"Yin","year":"2015","journal-title":"IEEE J. Selected Topics Appl. Earth Obs. Remote Sens."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Xu, X., Zhang, X., and Zhang, T. (2022). Lite-yolov5: A lightweight deep learning detector for on-board ship detection in large-scene sentinel-1 sar images. Remote Sens., 14.","DOI":"10.3390\/rs14041018"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1016\/j.isprsjprs.2020.05.016","article-title":"HyperLi-Net: A hyper-light deep learning network for high-accurate and high-speed ship detection from synthetic aperture radar imagery","volume":"167","author":"Zhang","year":"2020","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_18","first-page":"1","article-title":"A mask attention interaction and scale enhancement network for SAR ship instance segmentation","volume":"19","author":"Zhang","year":"2022","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1016\/j.isprsjprs.2021.10.010","article-title":"Balance learning for ship detection from synthetic aperture radar remote sensing imagery","volume":"182","author":"Zhang","year":"2021","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"108365","DOI":"10.1016\/j.patcog.2021.108365","article-title":"A polarization fusion network with geometric feature embedding for SAR ship classification","volume":"123","author":"Zhang","year":"2022","journal-title":"Pattern Recognit."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1080\/07038992.2001.10854875","article-title":"Ocean surveillance with polarimetric SAR","volume":"27","author":"Yeremy","year":"2001","journal-title":"Can. J. Remote. Sens."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"552","DOI":"10.5589\/m04-002","article-title":"Ship detection and characterization using polarimetric SAR","volume":"30","author":"Touzi","year":"2004","journal-title":"Can. J. Remote. Sens."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"5403","DOI":"10.1109\/TGRS.2015.2422134","article-title":"Optimization of the degree of polarization for enhanced ship detection using polarimetric RADARSAT-2","volume":"53","author":"Touzi","year":"2015","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1109\/36.297977","article-title":"Mueller and Kennaugh matrices in radar polarimetry","volume":"32","author":"Guissard","year":"1994","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"818","DOI":"10.1109\/TAP.1987.1144175","article-title":"On the optimum polarizations of incoherently reflected waves","volume":"35","author":"Papas","year":"1987","journal-title":"IEEE Trans. Antennas. Propag."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"328","DOI":"10.1364\/JOSAA.17.000328","article-title":"Characteristic properties of Mueller matrices","volume":"17","author":"Gil","year":"2000","journal-title":"JOSA A"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Cloude, S. (2009). Polarisation: Applications in Remote Sensing, OUP Oxford.","DOI":"10.1093\/acprof:oso\/9780199569731.001.0001"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"683","DOI":"10.1029\/JB092iB01p00683","article-title":"Imaging radar polarimetry from wave synthesis","volume":"92","author":"Zebker","year":"1987","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1049\/iet-rsn.2010.0092","article-title":"Pedestal height for sea oil slick observation","volume":"5","author":"Nunziata","year":"2010","journal-title":"IET Radar Sonar Navig."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1527","DOI":"10.1109\/LGRS.2016.2595058","article-title":"Analysis of Full and Compact Polarimetric SAR Features Over the Sea Surface","volume":"13","author":"Buono","year":"2016","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"5862","DOI":"10.1109\/TGRS.2016.2574561","article-title":"Polarimetric Analysis of Compact-Polarimetry SAR Architectures for Sea Oil Slick Observation","volume":"54","author":"Buono","year":"2016","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1109\/JSTARS.2012.2182760","article-title":"Ship and oil-spill detection using the degree of polarization in linear and hybrid\/compact dual-pol SAR","volume":"5","author":"Shirvany","year":"2012","journal-title":"IEEE J. Selected Topics Appl. Earth Obs. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"774","DOI":"10.1109\/36.7709","article-title":"Radar polarimetry: Analysis tools and applications","volume":"26","author":"Evans","year":"1988","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1007\/BF00913863","article-title":"Theories for the interaction of electromagnetic and oceanic waves\u2014A review","volume":"13","author":"Valenzuela","year":"1978","journal-title":"Bound.-Layer Meteorol."},{"key":"ref_35","unstructured":"NASA (2022, June 17). Gulf Coast, Mexico, Available online: https:\/\/uavsar.jpl.nasa.gov\/cgi-bin\/data.pl."},{"key":"ref_36","unstructured":"NDBC (2022, July 10). Gulf of Mexico (West), Available online: https:\/\/www.ndbc.noaa.gov\/obs.shtml."},{"key":"ref_37","unstructured":"PDP (2022, October 25). Sketch of a Fishing Trawler. Available online: https:\/\/www.publicdomainpictures.net\/en\/view-image.php?image=118770&picture=english-trawler."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"3812","DOI":"10.1109\/TGRS.2012.2185804","article-title":"Polarimetric analysis of backscatter from the Deepwater Horizon oil spill using L-band synthetic aperture radar","volume":"50","author":"Minchew","year":"2012","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"973","DOI":"10.1109\/36.175332","article-title":"Polarimetric discriminators for SAR images","volume":"30","author":"Touzi","year":"1992","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1029\/RS022i004p00529","article-title":"Imaging radar polarization signatures: Theory and observation","volume":"22","author":"Zebker","year":"1987","journal-title":"Radio Sci."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/22\/5813\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:20:15Z","timestamp":1760145615000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/22\/5813"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,11,17]]},"references-count":40,"journal-issue":{"issue":"22","published-online":{"date-parts":[[2022,11]]}},"alternative-id":["rs14225813"],"URL":"https:\/\/doi.org\/10.3390\/rs14225813","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,11,17]]}}}