Optimized design of a compact low-cost 4 element microstrip antenna array for WLAN

An innovative 4 element array topology of microstrip E shaped patches for use in WLAN applications is revisited and optimized by a novel Particle Swarm Optimization (PSO) implementation. This optimiser is capable to operate with a reduced number of cost function evaluations, since all evaluated antenna configurations and corresponding cost function values are saved. During the PSO optimization process, the fitness of the particle is evaluated by a full wave solver based on the moment of method. The used cost functions are constructed using s-parameters and the array gain in order to achieve the optimal performance. The operating frequency range is from 3.4 to 3.8 GHz and the gain of the array is more than 13 dB. The main beam direction is normal to the ground plane. Finally CST EM Studio is used to validate the global best antenna candidate structure.