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Timothy K. Stanton. Bhatia, Saurav Woods Hole Oceanographic Institution. Joint Program in Applied Ocean Physics and Engineering Woods Hole Oceanographic Institution Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science 2013-04-12T19:26:05Z 2013-04-12T19:26:05Z 2012 2012 http://hdl.handle.net/1721.1/78459 834074367 Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; and the Woods Hole Oceanographic Institution), 2012. Cataloged from PDF version of thesis. Includes bibliographical references (p. 65-67). The echo statistics of a randomly rough, randomly oriented prolate spheroid that is randomly located in a beampattern are investigated from physics-based principles both analytically and by Monte Carlo methods. This is a direct-path geometry in which reflections from neighboring boundaries are not a factor. The center of the prolate spheroid is assumed to be confined to the plane containing the MRA (maximum response axis). Additionally, the rotation of the prolate spheroid is assumed to always be in this plane. The statistics and, in particular, the tails of the probability density function (PDF) and probability of false alarm (PFA) are shown to be strongly non-Rayleigh and a strong function of shape of scatterer. The tails are shown to increase above that associated with a Rayleigh distribution with increasing degree of elongation (aspect ratio) of the scatterer and when roughness effects are introduced. And, as also shown in previous studies, the effects associated with the scatterer being randomly located in the beam contribute to the non-Rayleigh nature of the echo. The analytically obtained results are compared to Monte Carlo simulations for verification. by Saurav Bhatia. S.M. 67 p. eng Massachusetts Institute of Technology M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 Joint Program in Applied Ocean Science and Engineering. Electrical Engineering and Computer Science. Woods Hole Oceanographic Institution. Monte Carlo method Computer programs Mathematical models Non-Rayleigh scattering by a randomly oriented elongated scatterer Thesis application/pdf false Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="46691b25-1188-4471-ae2e-4e1aec81474e"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Non-Rayleigh scattering by a randomly oriented elongated scatterer</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>2012</PublicationDate> <Authors> <Author> <DisplayName>Bhatia, Saurav</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Joint Program in Applied Ocean Science and Engineering.</Keyword> <Keyword>Electrical Engineering and Computer Science.</Keyword> <Keyword>Woods Hole Oceanographic Institution.</Keyword> <Abstract>The echo statistics of a randomly rough, randomly oriented prolate spheroid that is randomly located in a beampattern are investigated from physics-based principles both analytically and by Monte Carlo methods. This is a direct-path geometry in which reflections from neighboring boundaries are not a factor. The center of the prolate spheroid is assumed to be confined to the plane containing the MRA (maximum response axis). Additionally, the rotation of the prolate spheroid is assumed to always be in this plane. The statistics and, in particular, the tails of the probability density function (PDF) and probability of false alarm (PFA) are shown to be strongly non-Rayleigh and a strong function of shape of scatterer. The tails are shown to increase above that associated with a Rayleigh distribution with increasing degree of elongation (aspect ratio) of the scatterer and when roughness effects are introduced. And, as also shown in previous studies, the effects associated with the scatterer being randomly located in the beam contribute to the non-Rayleigh nature of the echo. The analytically obtained results are compared to Monte Carlo simulations for verification.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>