Reconfigurable array design using parallel particle swarm optimization

Reconfigurable antenna arrays that are capable of radiating with multiple power patterns using a single power divider network are desirable for many applications. We use the particle swarm optimization (PSO) algorithm to perform dual-beam array optimization. Novel features of the PSO algorithm are its generality and ease of implementation over a wide range of electromagnetic problems. The problem investigated is as follows: design a reconfigurable dual-beam 20 element array such that the same amplitude distribution generates either a pencil-shaped or a sector power pattern, the difference being dependent only upon the phase distribution of the array. All excitation phases are set at 0° for the pencil-shaped beam, and are varied in the range -180°<θ<180° to form the sector pattern. This is a difficult problem because of the constraint that the same array must produce both patterns. We summarize the design parameters and specify graphically the masks within which the patterns should fit. Dual-beam patterns are achieved using the PSO to optimize the element excitation amplitude and phase directly.