Inversion of real transient radar data using the distorted-Born iterative algorithm

Real transient (time-domain) radar data are inverted using the distorted-Born iterative algorithm with a finite difference time domain (FDTD) forward solver. Application is to the nondestructive evaluation of concrete structures. Despite the fact that the source pulse shape was unknown, that its amplitude had to be calibrated by hand, that a 2-D wave propagation model was used, and that grid dispersion errors were present, reasonable reconstruction images were obtained. Certain artifacts that appeared in the reconstructed images may be attributed to the FDTD forward solver and are not inherent in the distorted-Born iterative method. Therefore, improvement in the inversion algorithm can be achieved by improving on the forward solver.<>