Characteristic Mode Analysis of U-Shaped Folded Dipole Antenna for WiMAX

U-Shaped Folded Dipole Antenna (UFDA) have been proposed for WiMAX. UFDA element is placed on the ground plane so that the occupied volume of the UFDA element is reduced as much as possible. In this paper, Characteristic Mode Analysis (CMA) is used for the analysis of UFDA, which is composed of UFDA element and the ground plane. As a result, it is found that two types of modes in the resonance of UFDA occur. The one is the mode of UFDA element and the other is the mode of the ground plane. Two frequency bands of WiMAX can be covered, when the shape of UFDA is adjusted by using the result of CMA.