Design of metasurface lenses for near-field GPR focusing via convex optimization

Abstract In ground-penetrating radar (GPR) systems, enhancing antenna radiation capability and subsurface energy levels is crucial for optimizing detection performance. To improve the radiation efficiency of GPR antennas, this study introduces a metasurface lens into the radar system. The primary contribution of this work lies in the application of convex optimization algorithms for field focusing, along with the design of a metasurface lens featuring independently controllable amplitude and phase. This innovative approach significantly enhances electromagnetic energy concentration at target locations. Both simulation and experimental results demonstrate that the proposed convex-optimization-assisted metasurface lens achieves ultra-low sidelobe precision focusing, surpassing the near-field focusing limitations inherent in traditional phase compensation algorithms.