A new algorithm for more accurate estimation of wave propagation velocity by common-offset survey method

This paper presents a new algorithm to estimate electromagnetic (EM) wave propagation velocity (v) with high-frequency 2GHz ground penetrating radar (GPR)’s shielded antenna. The data collection makes use common offset method with particular consideration of antenna’s separation distances and its corresponding triangulation geometry. This method calculates the distribution of discrete velocities at each point oblique to the embedded target object, analogous to the similar yet ambiguous curve fitting process of hyperbolas in most software. Validation test in air and a steel bar in concrete media were conducted and the results were satisfactory. Comparison with the tradition hyperbola geometry method was conducted and the results show that error on velocity analysis is significantly reduced by the proposed method. Based on the result, works on next stage will be about differentiation of velocity variations in concrete as a result of water seepage and leakage.