Particle swarm optimization for reconfigurable phase-differentiated array design

Multiple-beam antenna arrays have important applications in communications and radar. This paper describes a method of designing a reconfigurable dual-beam antenna array using a new evolutionary algorithm called particle swarm optimization (PSO). The design problem is to find element excitations that will result in a sector pattern main beam with low side lobes with the additional requirement that the same excitation amplitudes applied to the array with zero phase should result in a high directivity, low side lobe, and pencil-shaped main beam. Two approaches to the optimization are detailed. First, the PSO is used to optimize the coefficients of the Woodward-Lawson arrays synthesis method. Second, the element excitations will be optimized directly, using PSO. The performance of the two methods is compared and the viability of the resulting designs are discussed in terms of sensitivity to errors in the excitation. Additionally, a parallel version of the particle swarm code developed for a multi-node Beowulf cluster and the benefits that multinode computing bring to global optimization will be discussed. 0 2003 Wiley Periodicals, Inc.