单层传声器阵列信号空间重采样的声波分离方法

为了重构非自由声场中目标声源的声场响应,提出单层传声器阵列信号空间重采样的声波分离方法.以球面波函数为基函数,建立由系列球面波函数叠加表达的声场数学模型.基于近场声全息原理,利用单层传声器阵列面上空间重采样形成的两组声压测量信号,求解基函数系数,并重构出传声器阵列两侧声源各自的声场响应,实现声波分离.使用脉动球和振动球共同作用的非自由声场,检验了数学模型以及传声器信号信噪比、传声器阵列形状和面积、声源中心位置、频率等关键参数对声波分离精度的影响,并在全消声室内进行了实验验证.最后,对单层传声器阵列重采样的声波分离方法的实施给出了建议.

Sound wave separation metho d based on spatial signals resampling with single layer microphone array

In order to reconstruct the sound field of target sources in non-free sound field, a method of sound field separation and reconstruction is presented based on spatial resampling with single layer microphone array. In this method, the spherical harmonics are taken as the basis functions, and the spherical harmonics of different orders are added to describe the mathematical model of the sound field. On the basis of the nearfield acoustic holography, the coefficients of the basis functions can be obtained with two groups' sound pressures resampled from the microphone array, then the sound fields generated by the sound sources on both sides of the microphone array are separated. The mathematical model is validated against the benchmark values. A non-free sound field with a radially oscillating sphere and a transversely oscillating rigid sphere is built, and the impact of various parameters such as the signal to noise ratio, the geometric shape and area of the microphone array, location of target sound source, and frequency of signals on the accuracy of separation is examined. Finally, some suggestions are given for the industrial application of the above method.
Keywords： non-free sound field nearfield acoustic holography spatial resampling sound wave separation