基于声辐射模态理论的声场分离技术

为了消除复杂声场中干扰噪声对于近场声全息重建精度的影响,该文提出了一种基于单层阵列测量的声场分离技术.当目标声源和干扰噪声源为相干声源时,利用源强密度声辐射模态分析理论建立了声源与辐射声场的数学关系模型,通过对单层阵列测量的声压数据进行空间重采样得到两组子数据,构造各组子数据与目标声源和干扰噪声源的声辐射模态之间的数学公式,再求解公式中目标声源的各阶声辐射模态的展开系数,可重构目标声源在阵列处的声场响应,达到声场分离的目的.刚性脉动球声源与刚性脉动球干扰源、平板声源与刚性脉动球干扰源的数值仿真及对影响该方法的相关参数进行了详细研究,相关结果表明该方法具有较好的有效性和正确性.

Sound Field Separation Technique Based on Acoustic Radiation Modes

To eliminate the influence of the disturbing acoustic noise on reconstruction precision of near-field acoustic holography, a sound field separation technique with single hologram is proposed. In case the target source and the disturbing source are coherent, a mathematical model for the radi-ation of sources is set up by means of acoustic radiation mode theory. Two groups of sub-data are obtained by resampling acoustic pressures on a monolayer array and mathematical formulas are con-structed between each group of sub-data and the acoustic radiation mode of sources. Then the ex-pansion coefficients of the corresponding acoustic radiation modes can be calculated. Finally, the sound field response of the target source is reconstructed to complete sound field separation. Two nu-merical simulations were done to validate the proposed technique. In the first case, a simply support-ed plate is used as the target source and a rigid pulsating ball as the disturbing source, and in the second case, two rigid pulsating balls are used as the target and disturbing source respectively. Five parameters that would affect the validity of the proposed method were investigated in detail. Both the results show that the proposed approach is feasible and effective.