Sparse Wire-Grid Horn Antenna for the UHF Band

In this letter, the solid structure of a UHF-band horn antenna is transformed into a sparse wire-grid structure. The novelty of this work is that for the first time the actual sparse wire-grid structure was generated by applying Optimal Current Grid Approximation and its modifications to the original wire-grid structure. We present the antenna design details and experimental measurements of the antenna characteristics for these wire-grid structures. Comparative analysis of the antenna characteristics obtained by simulation and experiment shows that the original and sparse wire-grid structures are in good agreement with each other and with the solid structure. The generated sparse wire-grid structure is by 1.41 times less heavy than the original wire-grid structure and by 9.23 times - than the solid structure. The results of this work demonstrate the effectiveness of Optimal Current Grid Approximation and its modifications in generating sparse wire-grid structures with significantly less mass than the original wire-grid structures, as well as solid structures while maintaining the antenna performance.