Intelligent z -plane boundary condition-particle swarm optimiser for small array pattern synthesis

Abstract

This study concerns the radiation performance improvement of small periodic linear phased arrays in the presence of mutual coupling. An approach using a particle swarm optimiser (PSO) coupled with Schelkunoff's z-plane unit circle is proposed, with z-plane zeros constrained using adaptive boundary conditions (termed the intelligent z-plane boundary condition-PSO). It is shown that the proposed optimisation scheme has successfully achieved the target results for a range of problems presented including low-sidelobe scanned beam, and sector-beam pattern synthesis. The approach has consistent and faster convergence when compared with competitive techniques. Results showing significant improvement are presented using a Bowtie dielectric resonator antenna and uniform hemispherical elements.