A Compact Antipodal Tapered Slot Antenna With Artificial Material Lens and Reflector for GPR Applications

A novel compact antipodal tapered slot antenna (ATSA) for short-pulse ground penetrating radar (GPR) systems is presented. In order to improve the GPR antenna's radiation capability, we load the artificial material (AM) lens and reflector in the blank area of the antenna's substrate. Benefiting from the planar and compact structure of AM lens and reflector, original ATSA's directivity and radiation gain can be enhanced without decreasing its bandwidth or increasing any additional burden. To validate the proposed ATSA's performance, two prototypes (with and without AMs) are simulated, fabricated, measured, and compared. The simulation and experimental results indicate that the proposed ATSA has a -10 dB impedance bandwidth of 176.9% (0.43-7.0 GHz) and a -3 dB gain bandwidth of 111.1% (2.0-7.0 GHz). Besides, the radiation gain has been improved by about 2 dB while keeping the stable and endfire patterns over the frequency band. In addition, the transmission response in time domain indicates that it has a small ringing. The proposed ATSA is suitable for short-pulse GPR systems due to its excellent radiation performance. The introduced AM lens and reflector provide an effective way to improve antenna performance, which can be used in many other wireless systems.