Performance of a ground penetrating radar antenna in heterogeneous environments

Understanding how energy is transmitted and received by Ground Penetrating Radar antennas is crucial to many areas of the industry: antenna design, data processing and inversion algorithms, usage of antennas in GPR surveys, and interpretation of GPR responses. The radiation characteristics of antennas are usually investigated by studying the radiation patterns and directivity. For GPR antennas it is important to study these characteristics when the antenna is in environments that would typically be encountered in GPR surveys. Physically measuring antenna radiation patterns in such environments presents many practical difficulties, and there have been very limited numerical studies that combine real GPR antenna models with realistic environments. This paper presents a numerical investigation of the radiation characteristics of a high-frequency GPR antenna in a realistic environment. An advanced modelling toolset has been developed that enables detailed models of GPR antennas to be used with realistic heterogeneous soil models. In this initial investigation small differences in directivity have been observed between a lossless dielectric environment and a more realistic environment featuring a heterogeneous soil model. These findings are part of an on-going full parametric study incorporating a range of different soils, fractal weightings and also the inclusion of rough surface modelling