Enhanced Low Frequency GPR Measurement Using Optimized Vivaldi Antennas

This work presents a low frequency ground-penetrating radar (GPR) measurement system employing optimized Vivaldi antennas, targeting high penetration depth and enhanced range resolution. The radar integrates a modified edge-slot Vivaldi antenna operational from 75 MHz with a center frequency of 537.5 MHz and a bandwidth of 925 MHz. An initial GPR survey conducted in a ground-coupled mode over an asphalt surface successfully detects a buried utility pipe at approximately 2 m depth with good resolution. Detailed simulations, measurements and experimental results demonstrate the improved low frequency performance of the antenna, making it a suitable candidate for deep subsurface sensing.