A modified time-domain back projection algorithm for penetration imaging radar

This work describes the delay-sum back projection (DSBP) algorithm that can be used in penetration imaging radar, such as the ground-penetrating radar. In DSBP algorithm, the round-trip time of the electromagnetic signal is required to properly image the target area. The round-trip time in the multi-layered media is obtained using an interpolation method. The signal path length is first calculated for a few positions in the target area. Then, the signal path lengths for other positions are interpolated. The algorithm is flexible, accurate, and fast.