大气次声源定位算法及误差分析

逐步多通道相关方法是定位次声源的主要方法。该方法会忽略阵元的海拔高度差,从而引入误差。文章分析了基于广义互相关的时间延迟估计算法,讨论了基于时延的平面波入射角定位方法。着重研究了逐步多通道相关方法的误差来源,确定了基于时延的定位方法是产生误差的主要原因,明确了大气次声源定位误差来源于忽略了阵元间的海拔高度差。基于最小二乘法推导了在不考虑阵元高度的情况下计算次声波入射角的方法。对存在高度差的4元中心三角阵型进行了误差仿真实验,在忽略阵元海拔高度差的条件下,各方向入射的次声波角度定位误差最大达到4°,特定阵型的阵元最大海拔高度差与入射角度计算误差成线性关系,并探讨了入射角度计算误差对主要参数和后续定位的影响。

Localization algorithm for infrasound source in air and its error analysis

The progressive multi-channel correlation (PMCC) method is the primary method for locating the infrasound source. However, this method introduces errors due to ignoring the altitude difference between array elements. In this paper, the time delay estimation algorithm based on the generalized cross-correlation is analyzed; the localization method based on incident angles of the plane wave with time delay is discussed; the source of errors of the progressive multi-channel correlation method is studied, and it is determined that the errors of the infrasound source localization come from ignoring the altitude difference between array elements. Based on the least squares method, the method of calculating the incident angles of the infrasound wave without considering element height is derived. The error simulation experiment of the triangular quaternion array with element height difference is carried out. The maximum localization errors in all directions under the condition of ignoring the altitude difference between array elements are 4°. The relationship between the maximum element altitude difference and the incident angle computation error is linear. The influence of the incident angle computation error on the main parameters and subsequent localization is discussed.