Synthesis of Planar Arrays Using Particle Swarms with Selection

In this work, two well-known classical PSO schemes have been modified by introducing a tournament selection strategy, commonly used in genetic algorithms, and the new hybrid PSO schemes (HPSO) have been applied to planar array synthesis. The classical PSO schemes with either synchronous or asynchronous updates of the swarm and a global topology are considered and appropriately modified by introducing a tournament selection strategy in order to increase search pressure and make the algorithm speed up convergence. Results comparing both classical and HPSO schemes are included and the pros and cons of the hybrid approach proposed are reported and discussed. The synthesis of the complex element weights to best meet certain far-field radiation pattern restrictions given in terms of 3D-masks has been considered as the canonical problem. Furthermore, representative synthesis results for a planar array to be considered as a 120 degrees sectored antenna for local multipoint distribution systems (LMDS) are also included.