Optimal design of switched beam antenna arrays using Particle Swarm Optimization

Adaptive antennas techniques are emerging as a promising solution to a number of problems in applications related to mobile communications. This paper presents a method for optimal design of switched beam planar antenna arrays based on the Particle Swarm Optimization (PSO) algorithm. Switched beam antenna arrays are a subset of smart antennas that that can enhance the capacity of a cellular system. PSO is a population based algorithm that exploits a set of potential solutions to the optimization problem, which are determined on the basis of social interactions between independent agents. The synthesis problem addressed is to find spatial and feeding configuration of array elements that conform to certain design constraints enforced on multiple diagrams of differentiated directive gains and values (beam forming). Two different fitness functions were evaluated on this basis; results obtained were correlated to requirements of vertical system integration. The proposed methodology is very flexible allowing the incorporation of additional factors such as coupling characteristics and feeding network constraints.