Corrosion mapping of the surface of metal plates using FMCW radar

Radar systems calculate detection and range by comparing transmitted and received signals. Frequencymodulated continuous wave radars (FMCW) rely on measuring the phase difference between the transmitted and received signals. The received signals provide valuable information, including distance, speed, and target characteristics. This study aims to create a corrosion map of metal plates using image processing techniques on collected FMCW records, representing a form of non-destructive testing (NDT) that evaluates the characteristics or structural integrity of materials, components, or systems without causing damage. After gathering the beat frequency associated with the target, initial data preprocessing is performed to generate data matrices, followed by image processing techniques for secondary mapping. The data dimensions required to construct an image are approximately 466,854 pixels. The beat frequency, or phase shift, varies at that frequency for both the foreground and background while adaptive windowing and thresholding are applied to the initial frames. Various image segmentation techniques are also utilized on the reconstructed image to validate the results visually. The analysis indicated that the histogram similarity and Euclidean distance were 0.80 and 0.63, respectively, compared to the optically taken photo.