In this paper the maximum sidelobe level (SLL) reductions without and with central element feeding in various designs of three-ring concentric circular antenna arrays (CCAA) are examined using a real-coded Evolutionary Programming (EP) to finally determine the global optimal three-ring CCAA design. Standard real-coded Particle Swarm Optimization (PSO) and real-coded Particle Swarm Optimization with Constriction Factor and Inertia Weight Approach (PSOCFIWA) are also employed for comparative optimization but both prove to be suboptimal. This paper assumes non-uniform excitation weights and uniform spacing of excitation elements in each three-ring CCAA design. Among the various CCAA designs, the design containing central element and 4, 6 and 8 elements in three successive concentric rings proves to be such global optimal design set with global minimum SLL (−39.66 dB) as determined by Evolutionary Programming.
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