Performance of circular Yagi-Uda arrays for beamforming applications using particle swarm optimization algorithm

In this paper, a circular Yagi-Uda array (CYUA) for smart antenna applications is designed using the lengths and spacings from the optimum design of a three-element linear Yagi-Uda antenna. Then a modified circular Yagi-Uda array (MCYUA) is developed by adding 5 circular connecting wires to the inner parasitic elements (reflectors) to form a wire grid cylinder. The results are compared with those for uniform circular array (UCA) with 12 half-wave dipole elements. In our analysis, the method of moments (MoM) is used to compute the response of the arrays in a mutual coupling environment. The particle swarm optimization (PSO) algorithm is used to optimize the complex excitations of the adaptive arrays elements for beamforming.