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dc.contributor.advisorDavid L. Waring and David H. Staelin.en_US
dc.contributor.authorYip, Gina F. (Gina Fui Yuen), 1978-en_US
dc.contributor.otherMassachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.en_US
dc.date.accessioned2005-05-19T15:05:11Z
dc.date.available2005-05-19T15:05:11Z
dc.date.copyright2001en_US
dc.date.issued2001en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/16867
dc.descriptionThesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.en_US
dc.descriptionIncludes bibliographical references (p. 100-101).en_US
dc.descriptionThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.en_US
dc.description.abstractThis thesis describes the work done to research, implement, and compare various algorithms for the cancellation of echoes in a home environment, where the room impulse response is unknown and variable. The general problem, where the speaker's movements are completely unrestricted, is a very hard one, and research in this area has only begun in the last several years. Therefore, this thesis addresses a simplified version of the problem, where the impulse response of the multipath environment is assumed to be stationary within the duration of a verbal command. Given this assumption, which is reasonable for most situations, algorithms based on the complex cepstrum, autocorrelation, and delay and sum methods of echo cancellation were chosen and developed for the study. Many simulation tests were done to determine the behavior of the algorithms under different echo environments. The test signals were based on the simple delay and attenuation echo model with one microphone, and on a more realistic echo model, generated by the Cool Edit Pro software, with one or three microphones. The performance metrics were the number of errors and the percent of improvement in speech recognition by Dragon Systems' Naturally Speaking software. The results showed vast improvement for the cepstral domain methods on the simple echo signals, but the numbers were mixed for the complex model, one microphone cases. However, with three microphones, the delay and sum algorithm showed consistent improvement. Given that research in this specific area of 3D echo cancellation in a home environment, where 3D refers to the moving speech source, is still in its early stage, the results are encouraging.en_US
dc.description.statementofresponsibilityby Gina F. Yip.en_US
dc.format.extent101 p.en_US
dc.format.extent906287 bytes
dc.format.extent905998 bytes
dc.format.mimetypeapplication/pdf
dc.format.mimetypeapplication/pdf
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.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.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582
dc.subjectElectrical Engineering and Computer Science.en_US
dc.title3D echo cancellation in a home environmenten_US
dc.title.alternativeThree-dimensional echo cancellation in a home environmenten_US
dc.typeThesisen_US
dc.description.degreeM.Eng.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science.en_US
dc.identifier.oclc51677320en_US


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