Estimation of time delay and interface roughness by GPR using modified MUSIC

In civil engineering, roadway structure evaluation is an important application which can be carried out by ground penetrating radar. In this paper, firstly a signal model taking into account the influence of interfaces roughness (surface and interlayer) is proposed. In order to estimate the time delay and interface roughness, we propose a method composed of 2 steps: 1) a modified MUSIC algorithm is proposed for time delay estimation; 2) the interface roughness is estimated by using Maximum Likelihood method (MLE) with the estimated time delays. The proposed algorithms are tested on data obtained by a method of moments (MoM). Numerical examples are provided to demonstrate the performance of the proposed algorithm.