三轴四元非典型声强向量阵对低频声源全空间定向的理论与实验研究

Theoretical and Experimental Exploration on Two-Dimensional DOA Estimation for Low Frequency Sound Source with Non-typical Vector Acoustic Intensity Array

该文提出了应用3轴4元非典型声强向量阵在小尺度平台上对低频声源全空间定向的方法。该方法用四只传感器测量声强向量的3个正交分量,根据3个分量的几何关系来解出目标的方位。文中基于声信号的空间互谱分析,给出了声强向量阵的定向原理,并系统分析了其定向误差,包括有限差分误差、通道失配误差和环境噪声引起的误差。半消声室实验结果表明,在校正系统误差后,尺度为0.1m的非典型声强向量阵在各向同性噪声中的定向误差在1°左右,证实了该方法是可行的。

A new method of two-dimensional DOA （Direction of Arrival） estimation for low frequency sound source with the non-typical vector acoustic intensity array of small size is proposed. This array consists of 4 sensors on the 3 orthogonal axes, so as to measure the 3 components of the vector acoustic intensity. The azimuth and pitch angles of the sound source can be estimated from the 3 intensity components. The estimation errors, including the finite difference approximation error （FDAE）, the instrumentation channel mismatch error （ICME）, and the error caused by ambient noise, are studied systematically. Experiments conducted in semi-anechoic chamber show that, after correcting the FDAE and ICME, the precision of DOA estimation in isotropic ambient noise is about 1°. Both theoretical analysis and experimental results validate the effectiveness of this method.