Performance and influencing factors of acoustic grating based on signal enhancement

In the acoustic signal receiving section of underwater vehicle, an effective measure to improve surface acoustic impedance and reduce signal attenuation is to cover acoustic barrier plate of hydrophone array with high impedance material (signal conditioning plate). Compared with traditional full coverage mode, an acoustic grating (periodic installation of regulator plate array) can greatly improve the received signal gain and reduce the weight of the receiving segment. In order to deeply understand the signal enhancement mechanism and optimize the design of acoustic grating, the factors that influence the signal enhancement performance of acoustic grating from the aspects of width, thickness, incident angle and structure width ratio is studied. Simulation results show that the oblique incidence will change the symmetrical distribution of signal ratio (SR), but will not significantly change the acoustic performance of the structure. Wider and thicker regulating plate lead to stronger non-mirror scattering and better signal enhancement performance of structure. In practical application, geometric parameters of acoustic grating should be reasonably designed to meet multiple constraints of real environment to achieve optimal overall performance. In addition, the moderate width ratio can obtain a good overall acoustic performance.