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PubMed · 14753876

Time reversal and its application to tomography with diffracting sources.

Yuan Xu·Lihong V Wang
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Abstract

An exact time-domain method is proposed to time reverse a transient scalar wave using only the field measured on an arbitrary closed surface enclosing the initial source. Under certain conditions, a time-reversed field can be approximated by retransmitting the measured signals in a reversed temporal order. Exact reconstruction for three-dimensional broadband diffraction tomography (a linearized inverse scattering problem) is proposed by time-reversing the measured field back to the time when each secondary source is excited. The algorithm is verified by a numerical simulation. Extension to the case using Green's function in a heterogeneous medium is discussed.

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AcousticsAlgorithmsModels, TheoreticalRadiationTomographyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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Yuan Xu, Lihong V Wang. 2004-01-23. Time reversal and its application to tomography with diffracting sources.. https://doi.org/10.1103/physrevlett.92.033902

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