A 3D subsurface imaging technique based on distributed near-ground sensors: Investigation using scale model measurements

A high resolution subsurface imaging approach based on near-ground sensor networks operating in the VHF range that utilize ultra-wideband near-field focusing was recently proposed [1]. An accurate scattering model for targets buried in realistic subsurface environment modeled as a vertically stratified medium as well as an efficient inversion technique using an UWB near-field focusing were proposed. Numerical models were used to analyze the signal penetration depth in the VHF range and validate the proposed technique for targets that are buried at various depths [2]. In this paper, in order to investigate the performance of the proposed approach under practical limitations, laboratory-based scale model measurement results are utilized. In addition, various non-uniform sensor arrangements are tested to get an insight into how to best arrange a given number of sensors to cover the largest possible area and obtain the best possible lateral resolution.