On the Optimal Design of Non-uniform Circular Antenna Arrays

Abstract In this paper, the design of non-uniform circular antenna arrays of isotropic radiators with optimum side lobe level reduction is investigated. Two global evolutionary optimization methods (namely; the biogeography based optimization and the self-adaptive differential evolution) are used to determine an optimum set of weights and positions that provide a radiation pattern with optimum side lobe level reduction with the constraint of a fixed major lobe beamwidth. The results obtained from these two evolutionary are compared with those obtained using the Matlab function Fmincon which uses a sequential quadratic programming (SQP) method. The comparison shows that the design of non-uniform circular antenna arrays using SQP method provides a side lobe level reduction that is comparable to that obtained using global stochastic optimization methods.