Improved ultra-wide bandwidth bow-tie antenna with metamaterial lens for GPR applications

A new resistively loaded bow-tie antenna which can operate from 300 MHz to more than 3 GHz bandwidth is proposed. The proposed antenna employs a metamaterial lens to improve the forward gain and front-to-back ratio. The antenna radiates pulses with minimal late-time ringing and high peak amplitude. A stable radiation pattern obtained from 300 MHz to 2 GHz, makes it suitable for time domain as well as stepped frequency continuous wave (SFCW) GPR applications. The antenna is characterized by measurements of return loss, transmission scattering parameter, radiation pattern, gain, front-to-back ratio, and GPR B-scan with object buried under soil. The measured results are in good agreement with the simulation results.