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dc.contributor.authorDuda, Timothy F.
dc.contributor.authorPreisig, James C.
dc.date.accessioned2011-12-13T15:40:21Z
dc.date.available2011-12-13T15:40:21Z
dc.date.issued1999-01
dc.identifier.citationIEEE Journal of Oceanic Engineering 24 (1999): 16-32en_US
dc.identifier.urihttp://hdl.handle.net/1912/4932
dc.descriptionAuthor Posting. © IEEE, 1999. This article is posted here by permission of IEEE for personal use, not for redistribution. The definitive version was published in IEEE Journal of Oceanic Engineering 24 (1999): 16-32, doi:10.1109/48.740153.en_US
dc.description.abstractPropagation of 400-Hz sound through continental-shelf internal solitary wave packets is shown by numerical simulation to be strongly influenced by coupling of normal modes. Coupling in a packet is controlled by the mode coefficients at the point where sound enters the packet, the dimensions of the waves and packet, and the ambient depth structures of temperature and salinity. In the case of a moving packet, changes of phases of the incident modes with respect to each other dominate over the other factors, altering the coupling over time and thus inducing signal fluctuations. The phasing within a moving packet varies with time scales of minutes, causing coupling and signal fluctuations with comparable time scales. The directionality of energy flux between high-order acoustic modes and (less attenuated) low-order modes determines a gain factor for long-range propagation. A significant finding is that energy flux toward low-order modes through the effect of a packet near a source favoring high-order modes will give net amplification at distant ranges. Conversely, a packet far from a source sends energy into otherwise quiet higher modes. The intermittency of the coupling and of high-mode attenuation via bottom interaction means that signal energy fluctuations and modal diversity fluctuations at a distant receiver are complementary, with energy fluctuations suggesting a source-region packet and mode fluctuations suggesting a receiver-region packet. Simulations entailing 33-km propagation are used in the analyses, imitating the SWARM experiment geometry, allowing comparison with observationsen_US
dc.description.sponsorshipThis work was supported by the Office of Naval Research under Grant N00014-95-1- 0029 and Grant N00014-95-1-0051.en_US
dc.format.mimetypeapplication/pdf
dc.language.isoen_USen_US
dc.publisherIEEEen_US
dc.relation.urihttps://doi.org/10.1109/48.740153
dc.subjectCoupled mode analysisen_US
dc.subjectUnderwater acoustic propagationen_US
dc.subjectUnderwater acousticsen_US
dc.titleA modeling study of acoustic propagation through moving shallow-water solitary wave packetsen_US
dc.typeArticleen_US
dc.identifier.doi10.1109/48.740153


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