High resolution acoustic imaging method by non-synchronous measurements in three-dimensional space

In order to solve the problem of low resolution of acoustic imaging in three-dimensional space, a three- dimensional acoustic imaging method based on non-synchronous measurements is proposed. In this method, the spatially distributed sound source is scanned by moving the spherical microphone array, then the measured result of the micro- phone array with large aperture and high density is approximately obtained by using the non-synchronous measurement technique, and finally the image is obtained by the traditional beamforming algorithm. Simulation and experimental results show that the proposed method has narrower main lobe width and higher spatial resolution compared with beamforming with a single measurement, and can achieve high resolution imaging of sound source distribution in three- dimensional space. At the same time, the imaging results of this method can replace the simultaneous measurement results of multiple arrays without a reference microphone, which avoids the limitations of the reference microphone in increasing the number of channels and spatial arrangement.