Broadband acoustic invisibility and illusions
Abstract
Rendering objects invisible to impinging acoustic waves (cloaking) and creating acoustic illusions (holography) has been attempted using active and passive approaches. While passive methods are applicable only to narrow frequency bands, active approaches attempt to respond dynamically, interfering with broadband incident or scattered wavefields by emitting secondary waves. Without prior knowledge of the primary wavefield, the signals for the secondary sources need to be estimated and adapted in real-time. This has thus far impeded active cloaking and holography for broadband wavefields. We present experimental results of active acoustic cloaking and holography without prior knowledge of the wavefield so that objects remain invisible and illusions intact even for broadband moving sources. This opens novel research directions and facilitates practical applications including architectural acoustics, and stealth.
Keywords
Cite
@article{arxiv.2105.07709,
title = {Broadband acoustic invisibility and illusions},
author = {Theodor S. Becker and Dirk-Jan van Manen and Thomas Haag and Christoph Bärlocher and Xun Li and Nele Börsing and Andrew Curtis and Marc Serra-Garcia and Johan O. A. Robertsson},
journal= {arXiv preprint arXiv:2105.07709},
year = {2021}
}