Robust reconstruction of scattering surfaces using a linear microphone array
Robust reconstruction of scattering surfaces using a linear microphone array
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DOI：
10.1016/j.jsv.2020.115902
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发表时间：
2021-03
影响因子：
4.7
通讯作者：
G. Dolcetti;M. Alkmim;J. Cuenca;L. De Ryck;A. Krynkin
中科院分区：
文献类型：
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作者：
G. Dolcetti;M. Alkmim;J. Cuenca;L. De Ryck;A. Krynkin
对粗糙表面散射的声音进行分析，并通过安装在远场中的多个麦克风进行测量，可以估计未知的散射面轮廓。在前人工作的基础上，本文所用的方法是基于Kirchhoff积分方程的展开和线性化，并且适用于低密度的接收器。本文对原算法进行了改进，以减小测量偏差，并将其推广到宽带信号，以过约束问题，提高其稳健性。改进的方法与原始算法及其小扰动版本一起，对二维几何和具有空间幂函数谱的散射面进行了严格的评估。通过数值模拟，评估了测量装置和表面特性对重建不确定度的影响。针对三个已知表面轮廓获得的附加实验数据揭示了噪声和测量不确定性的影响。最佳测量配置需要在分辨率(高频时更高)和稳健性(低频时更高)之间进行权衡。建议的多频扩展至少部分克服了这一限制。由此产生的测量不确定度接近理论预期的约2%的声波波长。
The analysis of sound scattered by a rough surface and measured by multiple microphones positioned in the far field yields an estimate of the unknown scattering surface profile. Expanding from previous work, the approach used in this paper is based on an expansion and linearization of the Kirchhoff integral equation, and applies to a low density of receivers. Here, the original algorithm is modified in order to reduce the measurement bias, and extended to broadband signals to over-constrain the problem and improve its robustness. The improved method is rigorously assessed alongside the original algorithm and its small perturbation version, for a two-dimensional geometry and for scattering surfaces with a spatial power-function spectrum. The impact of the measurement setup and surface characteristics on the reconstruction uncertainty are evaluated by means of numerical simulations. Additional experimental data obtained for three known surface profiles reveal the impact of noise and measurement uncertainties. The optimal measurement configuration requires a trade-off between resolution (higher at high frequencies), and robustness (higher at low frequencies). This limit is overcome at least partially by the proposed multiple-frequency extension. The resulting measured uncertainties were close to the theoretical expectation of approximately 2% of the acoustic wavelength.