Predicting GPR performance for buried victim search & rescue

Ground penetrating radar (GPR) is a very common technique for exploring the subsurface. Lately, a different use of GPR has emerged from the need to search for and rescue victims in collapsed buildings and/or rock falls. Since the employment of ultra-wideband (UWB) radar devices is still a very new technique for rescue teams, many technology changes and best practices are being developed. One of the big concerns is the depth of sensing that can be achieved. Claims of seeing through 10s of meters of concrete rubble are not borne out by field measurements. This leads to false expectations in the search and rescue community and results in negative sentiments about the utility of the method. In this paper, we use of three-dimensional (3D) finite-difference time-domain (FDTD) numerical modelling to show how to establish realistic exploration depths and in the future provide some heuristic tools for assessing performance on real sites.