In this work, we theoretically propose and experimentally demonstrate a kind of non-reflecting acoustic metamaterial fence that is perfectly impedance matched to air in a wide range of incident angles and a broad frequency band. The metamaterial fence is composed of an array of rigid cylinders with alternating layers of different cylinder diameters. It is designed by a spatially dispersive effective medium theory and experimentally demonstrated by airborne sound reflectance measurements. Our work provides a unique approach to design and realize rigid acoustic structures that can robustly prohibit reflection and reverberation. Such structures may have important applications in general acoustics.

中文翻译：

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广角宽带不反射声超材料围栏

在这项工作中，我们从理论上提出并通过实验证明了一种非反射声超材料围栏，它在大范围的入射角和宽频带内与空气完美阻抗匹配。超材料围栏由一系列刚性圆柱体组成，这些圆柱体具有不同圆柱体直径的交替层。它是根据空间色散有效介质理论设计的，并通过机载声反射率测量进行了实验证明。我们的工作为设计和实现刚性声学结构提供了独特的方法，该结构可以牢固地阻止反射和混响。这样的结构在通用声学中可能具有重要的应用。