A study of antenna configuration for bistatic ground-penetrating radar

Recently, a public attention to ground subsidence due to the subsurface cavities in the urban area is growing. To prevent such catastrophe, a ground-penetrating radar (GPR) technique is being widely used to image and detect roadbed cavities. In this paper, properties in timedomain of antenna configurations are investigated to construct a bistatc GPR system. The system is categorized into two types: broadside and endfire, according to the antenna orientation. For each system, GPR signals scattered from spheric subsurface cavity model are compared and analyzed in the time domain. Then, for better energy penetration into the ground, impedance matching medium put below the antenna is studied. Considering the numerical results, the system that can provide a maximum level of signals scattered from the radar target of interest is determined. This study would help to give an insight into how a multi-channel antenna system is built to detect roadbed cavities in the urban area.