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A Compact Vivaldi Antenna With Artificial Material Lens and Sidelobe Suppressor for GPR Applications

A novel compact Vivaldi Antenna (CVA) for short-pulse ground penetrating radar (GPR) systems is presented. Artificial materials lens (AML) and sidelobe suppressor (SSR) are loaded to improve GPR Antenna’s radiation capability in the aperture and the flanks of the CVA. The simulation and experimental results indicate that the proposed CVA has a −10 dB impedance bandwidth of 100% (0.7-2.1 GHz) and a −3 dB gain bandwidth of 70.9% (1.0-2.1 GHz). Within the operating bandwidth of the CVA, AML primarily enhances the CVA’s high-frequency gain (1.4-2.1GHz), while the SSR primarily enhances the CVA’s low-frequency gain (0.7-1.4 GHz). Moreover, the CVA loaded with two kinds of artificial materials (AMs) has an average gain of 1 dB and 2 dB in the low-frequency and high-frequency parts, respectively. In addition, the transmission response with small ringing in time domain makes the proposed CVA suitable for short-pulse GPR systems. AML and SSR effectively enhance the gain of the CVA with a compact and space-saving loading method, which provides a new idea to enhance the gain of the CVA by artificial material.