Directional enhancement of triangular holographic acoustic leaky-wave antennas with reflectors

Triangular acoustic leaky-wave antennas, designed with holographic acoustic metasurfaces, represent an efficient approach for manipulating surface waves and achieving directional control. However, the performance of these devices is traditionally limited by the size of the patterned surface used to control the directivity of the leaky wave. To address this limitation, we introduce a holographic acoustic metasurface by incorporating surface wave reflectors to collimate surface waves along the patterned surface, thereby significantly enhancing beam directivity. Here, we employ holographic metasurfaces as forward leaky-wave antennas, effectively eliminating the backward mode and improving scanning capability. Experimental measurements demonstrate good agreement with theoretical and numerical analyses, validating the effectiveness of the proposed method. Furthermore, we extend this concept to generate two distinct sound beams within the holographic process. Acoustic full-wave simulations and experimental validations confirm the robustness of our proposed model. This holographic approach holds extensive applicability in areas such as sonar, ultrasound imaging, wave shaping, sensing, and acoustic communication, where the precise and efficient manipulation of sound waves is critical.