On the optimal synthesis of elliptical antenna arrays

Abstract

ABSTRACTIn this paper, firstly, we point out and correct a common mistake, in the literature, in the formulation of the array factor of an elliptical antenna array (EAA). Secondly, this paper deals with the optimal design of EAAs with low side lobes level using two recently proposed optimisation methods, namely, the Symbiotic Organisms Search (SOS) algorithm and the Antlion Optimisation (ALO) method. Two cases are considered. Firstly, the antennas are assumed to be evenly distributed over the ellipse contour, i.e. their positions are fixed, and the optimisation problem is to search for the current amplitudes (’s) that minimise the maximum side lobe level (SLL). Secondly, the antennas are assumed to be uniformly fed, i.e. In’s are assumed to be unity, and the optimisation problem is to search for the elements positions (along the ellipse) that minimise the maximum SLL. In both cases, SOS and ALO are used and their results are compared together. It is found that SOS is statistically better than ALO, though ALO consumes less CPU time to converge to the solution.