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Time reversal focusing of high amplitude sound in a reverberation chamber. | LitMetric

Time reversal focusing of high amplitude sound in a reverberation chamber.

J Acoust Soc Am

Acoustics Research Group, Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.

Published: February 2018

AI Article Synopsis

Article Abstract

Time reversal (TR) is a signal processing technique that can be used for intentional sound focusing. While it has been studied in room acoustics, the application of TR to produce a high amplitude focus of sound in a room has not yet been explored. The purpose of this study is to create a virtual source of spherical waves with TR that are of sufficient intensity to study nonlinear acoustic propagation. A parameterization study of deconvolution, one-bit, clipping, and decay compensation TR methods is performed to optimize high amplitude focusing and temporal signal focus quality. Of all TR methods studied, clipping is shown to produce the highest amplitude focal signal. An experiment utilizing eight horn loudspeakers in a reverberation chamber is done with the clipping TR method. A peak focal amplitude of 9.05 kPa (173.1 dB peak re 20 μPa) is achieved. Results from this experiment indicate that this high amplitude focusing is a nonlinear process.

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Source
http://dx.doi.org/10.1121/1.5023351DOI Listing

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