超声导波相移追踪的回波辨识方法

超声导波的多模式和频散特性使得其回波分析与定位异常复杂,在导波传播的模型解析的基础上,提出了一种基于频率相位追踪的回波辨识方法。首先,选取指定模式的直接散射信号的频域相位作为参考相位,将被分析信号各个波包的频域相位用参考相位进行归一化处理,得到各个波包相对参考波包传播距离的归一化阶次;然后,结合回波信号的传播路径分析,达到对各个波包定位辨识的目的。数值仿真和实验也验证了该方法的可行性和有效性。

Echo Identification of Phase Shift Tracking for Ultrasonic Guided Waves

The dispersion and multimode nature of a guided wave makes the analysis and identification of guided wave echoes complex. This paper proposes an echo identification method based on the frequency domain phase tracking. First, the frequency domain phase of the analyzed signals is extracted and normalized to the referenced signals of the direct propagation wave packet. Then, the normalized values are presented in an order spectrum. Finally, the location and recognition of each echo is determined with the analysis of the propagation path in the propagation medium. Simulation analysis and experimental results demonstrate the applicability and effectiveness of the proposed method.