Design of a coplanar bowtie antenna for WLAN and WiMAX application

A coplanar bow-tie antenna with triple-band operation for WLAN and WiMAX application is presented. The dual band-notched characteristic is realized by etching a U-shaped slot and a capacitively-loaded-loop (CLL)-shaped slot in the radiation patch. A triple band antenna, covering 2.24-2.70, 3.24-4.24, 4.84-6.00GHz, can be achieved through adjusting the positions and geometric parameters of the slots. A microstrip-to-CPS(coplanar striplines) transition with the overall dimensions of 70mm* 78.5mm* 0.8mm is used to feed the bowtie antenna as a wide band balun. The proposed triple-band bow-tie antenna consists of a SMA connector, a microstrip-to-CPS balun and radiation patch with U/CLL-shaped slots, simulated and optimized by using Ansys HFSS, a 3D full-wave finite element method solver. The results of the proposed antenna show good omnidirectional radiation patterns and more than 2.2 dB antenna gain, which are suitable for application in the WLAN/WiMAX systems.