Design and Simulation of a Wideband GPR Antenna with FSS-MA Shielding

In order to improve the radiation bandwidth of the ground-coupled GPR antenna and the radiation performance in the preferred direction, a new wideband bowtie antenna with Frequency Selective Surface (FSS) shielding and Metamaterial Absorber (MA) is proposed in this paper. The proposed antenna composed of three elements: an original bowtie antenna working at the center frequency of 1GHz, a two-sided band-stop FSS coating, and a MA. The simulation results show that the proposed FSS-MA-bowtie antenna achieves a better performance in near-field radiation, VSWR and input impedance, comparing with the original bowtie antenna. The side radiation of the original bowtie antenna is efficiently suppressed by the band-stop FSS shielding and are absorbed by back reflection. Results show that the gain of the preferred (forward) radiation direction have increased by 4dB, and the bandwidth reaches 27% by employing the FSS-MA shielding mechanism. In addition, time-domain analysis results that reflected oscillation was reduced, which satisfies the requirements of a wideband GPR system.