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An Improved Based on the Time-reversed Image Method of the Plate-like Structural Defects

Combined with the scanning of the probe array, this paper proposes an imaging method of the plate- like structural defects based on matching pursuit and the theory of time reversal. First, Match pursuit algorithm is used to the original signal processing of guided wave detection to improve signal quality, and provides a good foundation for signal reconstruction. Then it does algebraic difference of the signal before plate injury and the signal after injury to obtain the difference signal, and it uses the difference signal as time reversal excitation signal to obtain a set of time reversal signal. Last, the time-reversed signals are re-energized in the finite element model to simulate the actual plate, and damage imaging is realized in accordance with the principle of synthetic imaging. Experimental results show that this method can accurately extract the envelope of the signal, and more accurately detect the position of the defect, the range and other characteristics. Copyright © 2013 IFSA.