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PubMed · 11831798

Super-resolution in time-reversal acoustics.

Peter Blomgren·George Papanicolaou·Hongkai Zhao
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Abstract

The phenomenon of super-resolution in time-reversal acoustics is analyzed theoretically and with numerical simulations. A signal that is recorded and then retransmitted by an array of transducers, propagates back though the medium, and refocuses approximately on the source that emitted it. In a homogeneous medium, the refocusing resolution of the time-reversed signal is limited by diffraction. When the medium has random inhomogeneities the resolution of the refocused signal can in some circumstances beat the diffraction limit. This is super-resolution. A theoretical treatment of this phenomenon is given, and numerical simulations which confirm the theory are presented.

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AcousticsHumansModels, TheoreticalTime FactorsTransducersJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Peter Blomgren, George Papanicolaou, Hongkai Zhao. 2002. Super-resolution in time-reversal acoustics.. https://doi.org/10.1121/1.1421342

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