Generating Sparse Wire-Grid Antennas Using Maximum Current-based Optimal Current Grid Approximation

The rapid advancement of telecommunication systems demands antennas with reduced mass and size. Wire-grid structures serve as effective alternatives to traditional solid metal antennas by significantly reducing their mass. The Optimal Current Grid Approximation recently proposed approach has introduced sparse wire-grid structures with further mass reduction but poses fabrication challenges, prompting modified approaches. However, the previously proposed modified approaches only focused on overcoming the difficulties in fabrication, without considering the current distribution, resulting in structures with characteristics different from those of the original wire-grid structure. To overcome these limitations, we propose the“Maximum Current-based”Optimal Current Grid Approximation, a novel approach that selectively reconnects wires with maximum current, improving the radiation performance of the sparse structure and aligning antenna characteristics more closely to those of the original wire-grid structure. Applied to a UHF-horn antenna, the sparse structures generated using the proposed approach were analyzed and their antenna characteristics were compared with those of the sparse structures obtained using other approaches and the original wire-grid structure, which in turn were compared with those from previous studies obtained numerically by different methods and experimentally for solid antenna prototypes. The performed comparative analysis confirmed that the proposed approach generates sparse wire-grid structures with antenna characteristics closer to those of the original wire-grid than other approaches, demonstrating its effectiveness. In addition, based on the simulation results, the sparse wire-grid structure is generated to verify the effectiveness of the proposed approach. The obtained experimental results demonstrate the effectiveness of the proposed approach in generating sparse wire-grid antenna with mass 1.41 times less than the original wire-grid antenna and 7.63 times less than the solid antenna while maintaining the required characteristics.