Efficient Inverse Scattering Algorithm by Incorporating RPM Method for Microwave Non-destructive Imaging

摘要

Microwave non-destructive testing (NDT) is promising for detection of an air cavity or a metallic corrosion buried into concrete road or tunnel. The distorted born iterative method (DBIM) is one of the most effective approaches to reconstruct dielectric map and recognize a high contrast object. However, in an actual NDT observation model, it must be assumed that only reflection field is available, which makes the ill-posed problem extremely difficult. To solve this problem, the range points migration (RPM) based object area extraction scheme is incorporated into the DBIM, where the area of region of interest (ROI) is considerably downsized to reduce the number of unknowns in the DBIM. The finite-difference time-domain (FDTD) based numerical simulation tests demonstrate that our proposed method effectively enhance the accuracy of dielectric map reconstruction for the sparsely distributed object model.