Cross-correlation Phase Correction Method on Ultrasonic Synthetic Focused Signal Distortion

Synthetic aperture ultrasonic imaging is currently widely used in railway, aviation, automobile manufacturing and petrochemical, major in non-destructive testing the defects of key components and materials, and showing them in form of image. Due to inhomogeneity of testing materials and errors of detection systems, detected signals have phase errors, and distortion exists on synthesis images. This paper presents an effective phase correction method on ultrasonic synthetic focused signal distortion. A parameter, the relative signal-to-noise ratio, is introduced to be the indicator for later analysis. Via experimental results and the relative signal-to-noise ratios of the synthetic focusing images before and after phase correlation, the feasibility of the program is proved. Thus, the phase correction method here is worth putting the use into various ultrasonic application fields.