Study of Subsurface Roughness Impact on GPR Performance Using Modelling and Simulation

Numerical modelling and simulation for Ground-Penetrating Radar (GPR) were done to characterize and quantify the effect of subsurface roughness on GPR performance at 500 MHz operating frequency. An open-source electromagnetic solver was utilized for modelling multiple scenarios with various subsurface roughness and its numerical simulations. The detailed quantitative analysis for GPR signal losses was attempted in different subsurface roughness scenarios by using Normalized Energy (NE) and Signal-to-Clutter Ratio (SCR). This work also included the different fractal window sizes, i.e. variation of height of roughness with mean surface which define dynamic range of roughness. Quantitative results and analysis showed continuous decreasing trend in SCR with respect to increase in subsurface roughness. There was also a significant drop observed in SCR with increasing window size. The overall loss of signal has been quantified with respect to smooth interface. Hypothesis test has also been carried out to ensure and validate the subsurface roughness effect on GPR performance via signal-to-clutter ratio.