Linear antenna array synthesis with modified invasive weed optimisation algorithm

Abstract

Linear antenna array design is one of the most important electromagnetic optimisation problems of current interest. This article describes the application of modified version of a recently developed metaheuristic algorithm, known as the invasive weed optimisation (IWO), to optimise the spacing between the elements of the linear array to produce a radiation pattern with minimum side lobe level and null placement control. IWO is a novel ecologically inspired algorithm that mimics the process of weeds colonisation and distribution and is capable of solving general multi-dimensional, linear and non-linear optimisation problems with appreciable efficiency. For this application, we modified the classical IWO by introducing a more explorative routine of changing the mutation step-size with iterations. Three design examples are presented that illustrate the use of the IWO algorithm, and the optimisation goal in each example is easily achieved. The results of the modified IWO algorithm have been shown to meet or beat the results obtained using other state-of-the-art metaheuristics like the classical IWO, genetic algorithm (GA), particle swarm optimisation (PSO), memetic algorithms (MA), and tabu search (TS) in a statistically meaningful way.