Polarization-Reconfigurable Loop Antenna for Remote Sensing Radar Systems

This article presents the development of a circularly polarized antenna for VHF (Very High Frequency) applications, enabling switching between RHCP (Right-Hand Circular Polarization) and LHCP (Left-Hand Circular Polarization) for radar systems. The numerical validation of the proposed antenna was performed using Ansys HFSS software based on the Finite Element Method. Simulated and measured results for impedance matching are presented, with particular emphasis on the influence of a ground plane on the antenna performance. Additionally, gain results for both RHCP and LHCP polarizations are discussed, as well as the impact of phase difference on the antenna's axial ratio.