Synthesis of circular antenna arrays for reduction of side lobe and first null beamwidth using PSOIIW

A design problem of non-uniform circular antenna arrays for maximum reduction of both side lobe level and first null beamwidth is dealt with. This problem is modeled as a simple optimization problem. The method of particle swarm optimization with improved inertia weight (PSOIIW) is used to determine an optimal set of current excitation weights and antenna inter-element spacing that provides radiation pattern with maximum side lobe level (SLL) reduction and much improvement on first null beamwidth (FNBW) as well. Circular array antenna laying on x-y plane is assumed. PSOIIW is applied on circular arrays of 8-, 10-, and 12-elements. Various simulation results are presented and hence performances of side lobe and FNBW are analyzed. Experimental results show considerable reductions of both side lobe and FNBW with respect to the uniform case and some standard algorithms GA [7], PSO [8] and SA [14] applied to the same problem.