Efficient Design of Super-Directive Antenna Array Using Schelkunoff Method and Genetic Algorithm

Tightly packed super-directive antenna arrays with complex excitation functions are of recent interest in space communication. In this article, Schelkunoff polynomials and genetic algorithms (GA) are used to formulate the super-directive array excitation functions. The proposed technique used to calculate the antenna properties considerably reduces solver time compared with professional simulators. A packed linear array with an antenna aperture of $2.85\lambda$ and element spacing of $0.3\lambda$ (center-to-center) is designed to demonstrate a 66.67% increase in directivity, reduced sidelobes, and improved null accuracy as proof of concept. The calculated antenna responses agree well with the results of a professional simulator (HFSS), where the proposed method requires 90% less calculation time compared with the simulator. The experimental results verify the predicted responses and demonstrate a 5-dB increase in the antenna directivity compared with a conventional array.