Bandwidth maximization of a vertical U-shaped folded dipole antenna designed for WiMAX

This study presents the method of maximizing the resonant bandwidth of a vertical U-shaped folded dipole antenna (VUFDA) that projects from a small ground plane, designed for WiMAX applications in two frequency bands of 2.3~2.7 GHz and 3.4~3.8 GHz. By applying a suitable formulation of the objective function which represents the resonant bandwidth of VUFDA in a particle swarm optimization (PSO), an optimal shape of VUFDA is derived, which has the maximum possible bandwidth that includes the two WiMAX bands (2.31~4.3 GHz for VSWR≤3).