Digitally controlled steered dual beam pattern synthesis of a rectangular planar array antenna in a range of azimuth plane using evolutionary algorithms

This paper presents a pattern synthesis method to generate dual-beam patterns of a rectangular planar array of isotropic antennas in a particular scanning angle using Evolutionary Algorithms. The dual-beam patterns are cosec2 pattern and pencil beam pattern, and both the patterns are steered to an elevation angle of 20 degrees (θ = 20◦). Moreover, each pattern is synthesized in three azimuth planes (φ = 0◦, 5◦, and 10◦). The isotropic elements are uniformly spaced, and nonuniform excitations are applied to achieve the desired patterns. These patterns are obtained by applying the optimum set of common elements amplitude and phases for the cosecant-squared pattern only. The optimum 4-bit discrete amplitudes and 5-bit discrete phases are produced using Differential Evolutionary (DE) Algorithm, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) Algorithm, and Firefly Algorithm (FA). These discrete excitations are helpful to reduce the Dynamic Range Ratio (DRR) and the design complexity of the feed networks. The excitations are also verified in a range of arbitrarily chosen azimuth planes. The patterns are generated in the same steering angle with minor variations of the desired parameters. The outcomes established the superiority of DE over PSO, GA, and FA and the effectiveness of the proposed method. © 2021, Electromagnetics Academy. All rights reserved.