Improving Time Resolution of Ultrasonic Signals with Frequency-Domain Sparse Blind Deconvolution (FSBD) Method
Improving Time Resolution of Ultrasonic Signals with Frequency-Domain Sparse Blind Deconvolution (FSBD) Method
复制标题
利用频域稀疏盲解卷积 (FSBD) 方法提高超声信号的时间分辨率
DOI：
10.1007/s10921-022-00869-y
复制
发表时间：
2022-06-01
影响因子：
2.8
通讯作者：
Jin，S. J.
中科院分区：
文献类型：
--
作者：
Sun，X.;Lin，L.;Jin，S. J.
提高超声检测的时间分辨力是超声检测中普遍关注的问题，而参考信号对多路重叠信号的解耦和解释有着重要的影响。本文提出了一种频域稀疏盲反卷积（FSBD）方法来提高超声信号的时间分辨率，而不需要任何参考信号。采用匹配追踪（MP）算法去除噪声，实现信号重构。在此基础上，对去噪后的信号进行同态变换，并结合基于稀疏性的l1和l2范数约束，构造了提高时间分辨率的频域目标函数。通过实验，利用FSBD方法对多层试样和小缺陷进行了定量检测。结果表明，通过对多个重叠信号的解耦，可以实现半波长尺度的被测目标的识别。最后，将FSBD方法与最小熵反褶积和同态反褶积方法进行了比较。讨论了散射/反射回波数K与正则化参数μ之间的关系，合理地解决了正则化问题。
The improvement of time resolution is commonly concerned in ultrasonic testing, while the reference signal significantly influences the decoupling and interpretation of multiple overlapped signals. In this paper, the frequency-domain sparse blind deconvolution (FSBD) method is proposed to enhance the time resolution of ultrasonic signals without using any reference signal. The matching pursuit (MP) algorithm is introduced to remove noise for signal reconstruction. On this basis, homomorphic transformation is applied to the de-noised signal, and thel1andl2norm constraints based on sparsity are combined to construct a frequency-domain objective function for improving time resolution. The multilayer specimens and small defect were quantitatively detected using the FSBD method by experiments. The results demonstrate that the to-be-measured object with a size of half-wavelength can be identified by decoupling the multiple overlapped signals. Finally, the FSBD method is compared with minimum entropy deconvolution and homomorphic deconvolution. The relationship between the number of scattered/reflected echoesKand the regularization parameterμis discussed to solve reasonably the regularization problem.