A modified three-circular-ring monopole antenna for WLAN/WiMAX triple-band operations

In this paper, a novel triple-band modified three-circular-ring monopole antenna with a rectangular slot in the ground plane for WLAN/WiMAX applications is proposed. The proposed antenna consists of two circular rings and one open-ended circular ring. The numerical and experiment results demonstrated that the proposed antenna satisfied the -10 dB impedance bandwidth requirement while simultaneously covering the WLAN and WiMAX bands. Furthermore, this paper presents and discusses the 2D radiation patterns and 3D gains according to the results of the experiment.