Planar Multi-band T-shaped Monopole An- Tenna with a Pair of Mirrored L-shaped Strips for Wlan/wimax Operation

A novel compact design of planar T-shaped monopole antenna with multi-band operation for WLAN/WiMAX system is proposed. By insetting a pair of mirrored L-shaped monopole strips, multi resonant modes close to 2.45/3.5/5.5 GHz band are excited to meet the specifications of WLAN/WiMAX system. And, the obtained impedance bandwidth across the operating bands can reach about 160/1100/2690MHz for the 2.45/3.5/5.5 GHz bands, respectively. Only with the antenna size of 30×42×0.8mm3, the proposed monopole antenna has the compact operation with more than 20% antenna size reduction. The measured peak gains and radiation efficiencies are about 3.2/3.5/5.4 dBi and 72/98/96% for the 2.45/3.5/5.5 GHz band, respectively, with nearly omni-directional pattern in the XY -plane.