Ground-coupled antenna array for step-frequency GPR

This paper describes a new broadband ground coupled antenna array for step-frequency GPR operating continuously over the frequency range from 200 MHz - 3 GHz. The broad frequency range makes the array suitable both for high resolution shallow imaging and deeper investigations where efficient coupling of energy into the ground is crucial. A method for estimating penetration depth based on signal variance is described. The paper contains data examples from the new antenna array and also contains comparison with similar data from an air-coupled bowtie array. Finally, the paper discusses the benefits and disadvantages using air-coupled versus ground-coupled antennas for various applications.