Miniaturization of dipole antenna for low frequency ground penetrating radar

Abstract

In this paper, a miniaturized dipole antenna operating at 100MHz frequency for Ground Penetrating Radar (GPR) application is presented. A conventional dipole antenna length is half of its lowest operating frequency wavelength. As low frequency GPR system is vital for high depth penetration, the size of the antenna used reduces its easy handling and portability. Therefore, the technique of miniaturizing a dipole antenna by adding extra radiating arms is presented here. The antenna design and analysis is carried out using Advanced Design System (ADS) and FEKO simulation software, and a network analyser is used to validate the prototype antenna performance. The antenna of 66.5×22 cm dimension, fabricated on an FR4 substrate exhibits a frequency resonance at 104 MHz with 8MHz of −10 dB bandwidth. The proposed antenna radiates in omnidirectional pattern and features 55% reduction in length compared to a conventional dipole antenna of same frequency operation.