Design of phase-differentiated dual-beam concentric ring array antenna using differential evolution algorithm

In this paper, the authors propose a pattern synthesis method to generate a dual radiation pattern of pencil/sector beam pair of a concentric ring array of isotropic elements with desired sidelobe levels by switching between the radial phase distribution among the elements which shares a common amplitude distribution. The optimum set of radial amplitude and radial phase distributions for generating dual radiation patterns with lower sidelobe levels are computed using Differential Evolution algorithm. The array with optimum radial amplitude and zero radial phase distributions generate a pencil beam while the array with same amplitude but optimum radial phase generates a sector beam in the vertical plane.