Time delay and surface roughness estimation by subspace algorithms for pavement survey by radar

In civil engineering, ground penetrating radar is widely used for road pavement surveys. In contrast to the existing literature, the influence of interface roughness (surface and interlayer roughness of stratified media) is accounted for within the scope of the data processing of radar signals. The rigorous electromagnetic method PILE (propagation inside layer expansion) provides the simulated data. The observed frequency variations of the radar magnitude introduce some shape distortion on the radar wavelet. An adaptation of the root-MUSIC algorithm is proposed on the basis of the work. As a result, it is allowed to jointly estimate the time delay and the interface roughness.