This paper presents an accurate model of a monostatic stepped-frequency continuous-wave (SFCW) ground-penetrating radar (GPR). The model takes into account the multiple reflections occurring between the soil, target and antenna, which are a transverse electromagnetic (TEM) ultra-wide band (UWB) horn. The antenna radiation pattern is accounted for by a Huyghens cosinusoidal distribution of electric and magnetic current located on the aperture. The model is validated by experiments, involving dielectric targets embedded in a sandbox. These experiments validate altogether the radar modeling, as well as the MoM and the dyadic Green's functions (DGFs) used in the numerical algorithms.
van den Bosch, I., Lambot, S., Acheroy, M., Huynen, I., & Druyts, P. (2006). Accurate and efficient modeling of monostatic GPR signal of dielectric targets buried in stratified media. Journal of Electromagnetic Waves and Applications, 20(3), 283-290. https://doi.org/10.1163/156939306775701704 (Original work published 2006)