为有效解决近场声全息（Near-field Acoustic Holograph，NAH）技术在水下振动声源识别方法中面临不适定性问题，将平面 NAH 技术的声源识别过程转化为线性系统的求解过程，探明声源识别中不适定性问题产生的根源，考虑全息面测量声压和传递矩阵均存在误差，提出牛顿迭代的总体最小二乘（NTLS）正则化方法稳定 NAH 重建过程。新方法以 TLS 正则化算法为基础建立目标函数，将目标函数改化为具有凸函数的性质；然后采用具有二阶收敛速度牛顿迭代法求解；基于 L 曲线法特性，提出自适应迭代方法确定正则化参数。开展了 NAH 仿真和试验研究，提出构建良态传递矩阵的策略，最终验证了 NTLS 正则化的 NAH 技术在水下振动声源识别和定位中具有较好的精度。%Near field acoustic holography (NAH)is a very powerful tool for identifying sound sources.The identification process based on NAH was firstly converted into solving linear equations here,it was a linear,ill-posed inverse problem.And then,the ill-conditioned property of the ill-posed problem was ascertained.To find meaningful solutions to such a system,a novel Newton iteration total least squar (NTLS)method when both the transfer matrix and the measured sound pressure were contaminated by errors was proposed.The NTLS method included three parts.Firstly, Tikhonov regularization for a TLS problem was converted into an unconstrained optimization problem with properties of a convex function,the optimization problem was solved with Newton iteration method.Secondly,the adaptive strategy for selecting regularization parameters was established.Finally,the robustness and effectiveness of the proposed method were demonstrated with NAH simulations and tests. The results showed that the NTLS method provides a significant improvement for identifying and locating sound sources.
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