Genetic and TABU algorithm based array synthesis for the generation of a shaped beam antenna

Antenna designers are constantly challenged with the temptation to search for optimum solutions for the design of complex electromagnetic devices. The ability of using numerical methods to accurately and efficiently characterizing the relative quality of a particular design has excited the engineers to apply stochastic global evolutionary optimizers for this objective. Evolutionary techniques have been applied with growing applications to the design of complex electromagnetic systems. These schemes are finding popularity in electromagnetic as design tools and problem solvers because of their flexibility, veracity and ability to optimize in complex multimodal search spaces. This paper discusses the design and optimization of antenna arrays with special emphasis on Genetic Algorithm and TABU search method. It also illustrates the implementation procedure of Genetic algorithm and Tabu search algorithm in electromagnetic optimization problems. The optimization procedure is then used to design linear antenna array with specific array factor requirements. A comparative study of both design tools is done through simulation.

I. Introduction

The synthesis of equispaced linear array patterns with a shaped beam has been considered by some authors in the specialized literature [1]. There are many applications where the antenna pattern is required to be shaped to achieve a desired effect. In this paper a technique for the synthesis of shaped beam antenna pattern of a linear array is described. The fields radiated from a linear array are a superposition of the fields radiated by each element in the presence of other elements. Each element has an excitation parameter and this can be individually adjusted so that the excitation can be as desired. The excitation of each element will be complex, with amplitude and phase. Antenna array synthesis essentially involves determination of the amplitude and phase of the elements that will produce a desired radiation pattern. The synthesis of an antenna array with a specific radiation pattern, limited by several constraints is a nonlinear optimization problem. Tabu search method provides an efficient way to choose the design parameters. Although this method has been successfully applied in many areas such as Digital communication [2], signal processing [3], it is not well known to the electromagnetic community. It is the goal of this paper to introduce Tabu search technique to the electromagnetic community and demonstrate its great potential in electromagnetic optimizations.