Design and Performance Analysis of Planar Antenna for Ground Penetrating Radar Applications

Ground Penetrating Radar (GPR) is a non-invasive electromagnetic sensing technology widely employed in archaeology, geological surveying, infrastructure inspection, and environmental monitoring to detect buried objects, structural anomalies, and subsurface variations without excavation. The performance of a GPR system heavily depends on the antenna, which influences signal penetration, resolution, and imaging accuracy. Microstrip patch antennas are well-suited for GPR applications due to their compact structure, ease of fabrication, and ability to operate at specific frequencies. A 260 × 220 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> rectangular microstrip patch antenna with a single stub is designed and optimized to operate at 500 MHz, ensuring efficient subsurface imaging. Constructed on an FR4 substrate with a thickness of 1.6 mm and a dielectric constant of 4.4, the antenna achieves a return loss of -30.05 dB and a Voltage Standing Wave Ratio (VSWR) of 1.101, ensuring minimal power reflection and maximum energy transfer. The gain of 0.408 dB, combined with a directional radiation pattern featuring a main beam at 0°, supports precise and effective subsurface scanning. This optimized design meets the critical performance requirements for low-frequency GPR applications, enhancing imaging depth and clarity. Future advancements may focus on increasing gain and further refining the antenna structure to improve efficiency for deeper and more complex subsurface investigations.