Ground-Penetrating Radar Antenna Design for Homogeneous and Low-Loss Dielectric Multilayer Media
Keywords:Ground-penetrating radar, Multilayer problem, Pavement, Ricker wavelet, UWB antenna.
Non-destructive evaluation of multilayer media represents an electromagnetic inverse problem, usually solved with analysis techniques in the time and frequency domains. The time- domain analysis technique depends directly on the accurate detection of reflected peaks measured by ground-penetrating radar (GPR), which limits this technique when the reflected pulses overlap with each other or the transmitted signal. Therefore, this paper presents a new practical methodology to obtain the antenna design requirements (operating frequency and temporal response) that avoid overlapping reflected pulses. The major finding is that the proposed methodology enables the production of specific antennas for the analyzed homogeneous and low-loss dielectric multilayer problem, serving as a practical guide for GPR antenna design. A typical pavement example is analyzed to apply the methodology, and, as a result, an ultra-wideband (UWB) directive antenna with tolerable dispersion is obtained according to the design specifications. Finally, the antenna simulations were compared and validated with measurements.