粗晶材料超声检测信号的小波变换去噪方法

De-Noising method to ultrasonic inspection signal of Coarse-Grained materials on wavelet transform

摘要: 本文研究多尺度小波分析方法在粗晶材料超声缺陷信号增强中的应用.在分析晶粒噪声和缺陷信号频谱分布的基础上,提出一种基于小波变换系数软阈值处理再重构的方法来提高信噪比.实验结果表明,该方法具有很好的去噪效果,增强了缺陷的检出率.

Abstract: The application of wavelet transform to ultrasonic inspection of coarse-grained materials is discussed in this paper.To restrain the adverse effect of the scattering from coarse-grain,an algorithm using wavelet coefficient threshold pruning and reconstruction is provided to enhance SNR based on the discussion of the frequency spectrum distribution of the defect signals and grained noise.The experimental results show that the new method is more effective,and the defect is detected more easily.