Synthesis of linear array antenna for fixed level of side lobe level and first null beam width using particle swarm optimization

Abstract

In this paper, a very simple and powerful method for the synthesis of linear array antenna is proposed. This method ensures the desired level of side lobe level (SLL) along with the minimum desired value of first null beam width (FNBW). Method includes finding a set of non-uniform amplitude excitation using particle swarm optimization (PSO) and finding the appropriate value of uniform element spacing for the linear array, which qualifies the desired value of SLL and provides minimum desired FNBW value. PSO algorithm is a high-performance algorithm capable of solving general N-dimensional, linear and nonlinear optimization problems. Work in this paper includes, two-step method for getting the fixed value of SLL and minimum desired FNBW. In the first step, PSO is used for optimizing both SLL and FNBW, but the main emphasis is given for the desired SLL requirement to achieve. In the second step, SLL remains almost constant but FNBW is minimized to archive the desired value or even below the desired value of FNBW. The simulation results have shown that this technique is able to find the desired value of SLL with the very narrow FNBW.