An advanced numerical imaging procedure for GPR shallow surveys

The advances achievable in terms of reconstruction capabilities offered by an ad-hoc imaging procedure capable of accounting for the actual radiation features of a Ground Penetrating Radar (GPR) have been analyzed in this paper. The study is carried out by using a full-wave simulator, capable to reproduce the characteristics of the antenna system as well as the signals used for the actual illumination. This numerical analysis enables us to obtain an accurate determination of both the incident and the backscattered electromagnetic fields in the investigated scenarios for the application to a microwave tomographic approach. It is thus possible to derive indications about the variations in terms of reconstruction capabilities that are expected when a directive antenna illuminates a shallow buried target, whose dimensions are comparable with the probing wavelength. Numerical examples for reference cases are presented and discussed in order to assess how imaging is affected by the antenna model used in the implementation of the tomographic approach.