Wide-angle Scanning and Beam Optimization of Circularly Polarized Hemispherical Phased Array Antennas

Conformal phased arrays have received continuous attention from scholars due to their excellent beam scanning performance. In this paper, a circularly polarized hemispherical phased array is designed to achieve half-space beam scanning. The active element patterns (AEP) for each array element are extracted, and beam synthesis of the spherical array is conducted considering mutual coupling. The numerical experimental results are in good agreement with the High Frequency Structure Simulator (HFSS) simulation results, validating the effectiveness of the method. For conformal arrays, not all antenna elements contribute to the main beam, so it is necessary to determine which antenna elements are active and which are inactive. An adaptive evolution strategy based on the covariance matrix adaptation evolution strategy (CMA-ES) is employed to optimize the excitation phases of working antenna elements, greatly reducing side lobe level (SLL).