Optimized inter-element arc spacing and ring radius in the synthesis of phase-only reconfigurable concentric circular array antenna using various evolutionary algorithms

This paper presents a method based on the Moth Flame optimization evolutionary algorithm for the synthesis of Flat-top/pencil beam pair of dual beam reconfigurable concentric circular antenna arrays. This beam pair is generated with the help of the optimized inter-element arc spacing, ring radius and 6-bit discrete radial phases generated by the optimization algorithm. Zero-phases are used for the elements in the pencil beam and the radial phases controlled by the phase shifters are used for generating the flat-top beam. Amplitudes are kept to unity in both the beams. Experiments are carried out using fitness functions that include the side-lobe levels in both the beams along with the beamwidths in the pencil beam and a ripple value in the flat-top portion of the flat-top beam. In addition to it, experiments are also done for providing a null depth in one of the beam pair. The results obtained from the experiments using Matlab software show the effectiveness and superiority of this algorithm over other evolutionary algorithms like Bio-geography-based optimization algorithm and Imperialist competitive algorithms.