Triple-Band Slot Antenna with U-Shaped Open Stub FED by Asymmetric Coplanar Strip for WLAN/Wimax Applications

A novel compact microstrip planar slot antenna with triple-band operations for WALN and WiMAX applications is proposed. The antenna, which occupies an overall dimension of 35×19×1.6 mm, has a simple structure which consists of an asymmetric coplanar strip with a reverse G-shaped slot and a U-shaped open stub. The U-shaped open stub excites a resonant mode at 2.4 GHz. On the other hand the asymmetric coplanar strip could excite the resonant modes at 5.2 GHz. Meanwhile, the reverse G-shaped slot is aimed to excite resonant modes at 3.5 and 5.8 GHz. It has good omnidirectional radiation patterns in the azimuth plane and reaches 1.1 dBi at 2.4 GHz, 2.3 dBi at 3.5 GHz, 3.1 dBi at the band of 5 GHz. The designed antenna is simulated by HFSS software and a good agreement with experimental results is demonstrated.