Kind of magnetostrictive wave guide calibration signal processing method and apparatus

摘要

A magnetostrictive waveguide detection signal processing method and device, the method involving interception of a raw detection signal so as to obtain an analytical signal u(n) and further bandpass filtering to obtain x(n). The excitation signal length is set as L, letting M = [L/4], and R = [M/2]. With an initial i = 0, intercepting data x(i),..., (i+M-1), and building a matrix A wherein R*(M-R+1), then performing singular value decomposition on the matrix so as to obtain a singular matrix B and feature values »; setting to zero » values lower than the median to obtain matrix C, performing a reverse singular transformation on the matrix C to obtain matrix D, and reducing from matrix D a post-processed signal y and calculating the energy z thereof. Letting i = i+1, repeating the steps above until completing calculation of the energies of the post-processed signals of the selected analysis zone, then, on the basis of the distortion characteristics of the energy distribution graph, determining whether any defect is present in the signals. The present method effectively enhances the signal-to-noise ratio in magnetostrictive waveguide detection signals, and detection accuracy.