<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-09-20T23:33:32Z</responseDate><request verb="GetRecord" identifier="oai:dspace.mit.edu:1721.1/113758" metadataPrefix="dim">https://dspace.mit.edu/server/oai/request</request><GetRecord><record><header><identifier>oai:dspace.mit.edu:1721.1/113758</identifier><datestamp>2022-01-13T20:46:22Z</datestamp><setSpec>com_1721.1_7582</setSpec><setSpec>com_1721.1_7581</setSpec><setSpec>col_1721.1_131023</setSpec></header><metadata><dim:dim xmlns:dim="http://www.dspace.org/xmlns/dspace/dim" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="http://www.dspace.org/xmlns/dspace/dim http://www.dspace.org/schema/dim.xsd">
   <dim:field mdschema="dc" element="contributor" qualifier="author" lang="en_US">Carper, Scott Adams</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="other" lang="en_US">Woods Hole Oceanographic Institution.</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="department" lang="en_US">Joint Program in Applied Ocean Physics and Engineering</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="department" lang="en_US">Woods Hole Oceanographic Institution</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="department">Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science</dim:field>
   <dim:field mdschema="dc" element="contributor" qualifier="department">Massachusetts Institute of Technology. Department of Mechanical Engineering</dim:field>
   <dim:field mdschema="dc" element="coverage" qualifier="spatial" lang="en_US">r------</dim:field>
   <dim:field mdschema="dc" element="date" qualifier="accessioned">2018-02-16T20:04:37Z</dim:field>
   <dim:field mdschema="dc" element="date" qualifier="available">2018-02-16T20:04:37Z</dim:field>
   <dim:field mdschema="dc" element="date" qualifier="copyright" lang="en_US">2017</dim:field>
   <dim:field mdschema="dc" element="date" qualifier="issued" lang="en_US">2017</dim:field>
   <dim:field mdschema="dc" element="identifier" qualifier="uri">http://hdl.handle.net/1721.1/113758</dim:field>
   <dim:field mdschema="dc" element="identifier" qualifier="oclc" lang="en_US">1022267262</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Thesis: S.M. in Oceanographic Engineering, Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2017.</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science; and the Woods Hole Oceanographic Institution), 2017.</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Cataloged from PDF version of thesis.</dim:field>
   <dim:field mdschema="dc" element="description" lang="en_US">Includes bibliographical references (pages 885-86).</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="abstract" lang="en_US">A newly discovered double ducted acoustic environment present throughout much of the Beaufort Sea in the Arctic has a major effect on active acoustic transmissions. This work performs an in depth analysis of how the lower duct impacts the propagation of various active signals used commonly for acoustic communications or active sonar. First, this thesis performs a thorough modal analysis of the effect of the double ducted environment on long range propagation of a 300 Hz and 3500 Hz pulse. Signal excess is determined for the two different source pulses to quantify the effect of the lower duct on noise and SNR. Finally, channel capacity is calculated for the two frequency bands to evaluate operational impacts of the lower duct on acoustic communication systems in the Arctic.</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="statementofresponsibility" lang="en_US">by Scott Adams Carper</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="degree" lang="en_US">S.M. in Oceanographic Engineering</dim:field>
   <dim:field mdschema="dc" element="description" qualifier="degree" lang="en_US">S.M.</dim:field>
   <dim:field mdschema="dc" element="format" qualifier="extent" lang="en_US">86 pages</dim:field>
   <dim:field mdschema="dc" element="language" qualifier="iso" lang="en_US">eng</dim:field>
   <dim:field mdschema="dc" element="publisher" lang="en_US">Massachusetts Institute of Technology</dim:field>
   <dim:field mdschema="dc" element="rights" lang="en_US">MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.</dim:field>
   <dim:field mdschema="dc" element="rights" qualifier="uri" lang="en_US">http://dspace.mit.edu/handle/1721.1/7582</dim:field>
   <dim:field mdschema="dc" element="subject" lang="en_US">Joint Program in Applied Ocean Science and Engineering.</dim:field>
   <dim:field mdschema="dc" element="subject" lang="en_US">Mechanical Engineering.</dim:field>
   <dim:field mdschema="dc" element="subject" lang="en_US">Electrical Engineering and Computer Science.</dim:field>
   <dim:field mdschema="dc" element="subject" lang="en_US">Woods Hole Oceanographic Institution.</dim:field>
   <dim:field mdschema="dc" element="subject" qualifier="lcsh" lang="en_US">Sound</dim:field>
   <dim:field mdschema="dc" element="subject" qualifier="lcsh" lang="en_US">Sound Communication</dim:field>
   <dim:field mdschema="dc" element="subject" qualifier="lcsh" lang="en_US">Sonar</dim:field>
   <dim:field mdschema="dc" element="subject" qualifier="lcsh" lang="en_US">Radio frequency</dim:field>
   <dim:field mdschema="dc" element="subject" qualifier="lcsh" lang="en_US">Sound Communication systems</dim:field>
   <dim:field mdschema="dc" element="title" lang="en_US">Low frequency active sonar performance in the Arctic Beaufort Lens</dim:field>
   <dim:field mdschema="dc" element="type" lang="en_US">Thesis</dim:field>
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	&lt;Language>eng&lt;/Language>
   	&lt;Title>Low frequency active sonar performance in the Arctic Beaufort Lens&lt;/Title>
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   	&lt;PublicationDate>2017&lt;/PublicationDate>
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        	&lt;DisplayName>Carper, Scott Adams&lt;/DisplayName>
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    &lt;Keyword>Joint Program in Applied Ocean Science and Engineering.&lt;/Keyword>
    &lt;Keyword>Mechanical Engineering.&lt;/Keyword>
    &lt;Keyword>Electrical Engineering and Computer Science.&lt;/Keyword>
    &lt;Keyword>Woods Hole Oceanographic Institution.&lt;/Keyword>
   	&lt;Abstract>A newly discovered double ducted acoustic environment present throughout much of the Beaufort Sea in the Arctic has a major effect on active acoustic transmissions. This work performs an in depth analysis of how the lower duct impacts the propagation of various active signals used commonly for acoustic communications or active sonar. First, this thesis performs a thorough modal analysis of the effect of the double ducted environment on long range propagation of a 300 Hz and 3500 Hz pulse. Signal excess is determined for the two different source pulses to quantify the effect of the lower duct on noise and SNR. Finally, channel capacity is calculated for the two frequency bands to evaluate operational impacts of the lower duct on acoustic communication systems in the Arctic.&lt;/Abstract>
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