Recioui, Abdelmadjid2016-01-282016-01-28201505874246https://dspace.univ-boumerdes.dz/handle/123456789/2624Circular and concentric circular antenna array patterns are synthesized to generate array factors with minimum side-lobe level and high directivity. The comprehensive learning differential search algorithm is used for synthesizing a one-and a three-ring circular and concentric circular antenna array with thirty elements. This synthesis is done by finding the optimum inter-element spacing of rings, phases and /or positions that give optimum side lobe level. The computational results show that side lobe level is reduced significantly in non-uniform case for concentric in comparison with a single ringenAlgorithmsAntenna lobesLearning algorithmsOptimization Circular antenna arraysComprehensive learningComputational resultsConcentric circular antenna arraysHigh-directivityInter-element spacingSearch AlgorithmsSidelobe levelsOther