Sound Source Localization Using Piezoelectric Acoustic Metasurfaces

Nowadays, the sound source localization is widely applied in various fields, with a focus on arrays or algorithms. Meanwhile, acoustic metasurfaces have recently attracted enormous interest in material science. This paper proposed a kind of piezoelectric acoustic metasurface, whose structure is theoretically proved to be useful in sound field orientation or sound source localization. The metasurfaces consist of forty units made up of a resonance-like cavity and a piezoelectric composite sheet in air. By scanning through space and frequency, it has been investigated that the effective interval can reach 30 degrees <= theta <= 150 degrees and -200 <= x <= 200cm under far-field and near-field scenario, respectively. Meanwhile, the bandwidth of the structure was evaluated to be up to 800-900 Hz in both scenarios. In addition, this paper analyzed three factors affecting the interval: frequency, the size of the metasurface, and the number of elements. The results of this paper has opened up a new way for sound source localization and metasurfaces.