Sparse Structures of 3D Printed K/Ka-band Horn Antenna using OCGA and its Modifications

With the intensive evolution of 5G network technology, there are many challenges in the design of 5 G antennas, including small size, low mass, and interference immunity. Reducing the antenna mass and size is a challenging task. To solve this problem, wire grid approach based on method of moments has been widely used for solid surface approximation of multiple types of antennas. This approach achieves significant resource savings over other approaches while maintaining the desired antenna characteristics. In this paper, the surface of a K/Ka-band 3D printed horn antenna used in 5G network technology has been approximated by the wire grid approach. The obtained results were compared with the measurement and modeling results using other methods. The comparison shows that the results of the surface approximation approach using wire grid are more similar to the measurement results than the results of other methods. To further reduce the antenna mass, the optimal current grid approximation approach and its modifications were applied to the original wire grid antenna to create sparse antennas. Next, we present a detailed comparative analysis of the antenna performance obtained after applying different approaches with a variation of the grid element elimination tolerance value. In addition, we also present two specific examples of sparse antennas obtained after applying different approaches at grid element elimination tolerance of $50 \%$ and $80 \%$. A comparative analysis of the main characteristics over the operating frequency range of these sparse antennas is carried out. The study shows the high flexibility of the optimal current grid approximation and its modifications with respect to the balance between performance and cost, allowing manufacturers to evaluate and select the appropriate grid element elimination tolerance value for their specific requirements.