Broadband ultrathin sound diffuser based on the membrane-type coding metasurface
Published in Journal of Applied Acoustics, 2023
Abstract
A broadband ultrathin sound diffuser based on the membrane-type coding metasurface is proposed in this paper. The resonance units are constructed with mass-decorated membrane and air cavity. Two kinds of resonance units are designed with a reflection phase difference of 180◦. The acoustic metasurface consisted of these two units can produce broadband diffuse sound field. The near-field sound pressure distribution, the far-field sound pressure levels directivity patterns and the diffusion coefficient are calculated by the simulation software and compared with those of the flat plate. The simulation results show that the sound diffuser can effectively diffuse the incident waves and operate in a broadband frequency range.