A blind deconvolution approach to discontinuity location and characterization in ultrasonic nondestructive testing

This paper presents a new algorithm for discontinuity location and characterization using A-scan signals from an ultrasonic inspection system. The algorithm is based on solving an inverse problem in which the observation model is different from that traditionally used. In this model, the input vector represents the location of the geometrical center of the discontinuity and the scattering amplitude of the discontinuity is embedded in the impulse response of the ultrasonic inspection system. First, we jointly estimate the locations and the scattering amplitudes of the discontinuities from the acquired signals. Then, the geometrical parameters of the discontinuities are calculated from the estimated scattering amplitude. The method is tested to characterize side-drilled holes using both synthetic and real data. The results demonstrates the effectiveness of the algorithm.