Design of circular antenna arrays for the reduction of side lobe and first null beamwidth using BFO

Abstract

A design problem of non-uniform circular antenna arrays for maximum reduction of both the side lobe level (SLL) and first null beamwidth (FNBW) is dealt with. This problem is modeled as a simple optimization problem. The method of Bacteria foraging Optimization (BFO) is used to determine an optimal set of current excitation weights and antenna inter-element spacing that provide radiation pattern with maximum SLL reduction and much improvement on FNBW as well. Circular array antenna laying on x-y plane is assumed. BFO 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 the SLL and FNBW with respect to those of the uniform case and some standard algorithms GA [12], PSO [14] and SA [11] applied to the same problem.