Design Of Dual-Band Antenna For WLAN Applications

As one of the most effective wireless access methods, Wireless Local Area Network (WLAN) is one of the important components in wireless communications. With the promulgation of IEEE 802.11a/b/g protocols, it is more advanced to work at dual band and multimode WLAN which meet the requirements of WLAN protocols. The task of this literature is to design two dual-band WLAN antennas used for IEEE 802.11a protocol (5.15GHz-5.35GHz, 5.725GHz-5.875GHz) and IEEE 802.11 b/g protocols (2.4GHz-2.484GHz).Firstly, the literature presents a broadband and dual band planar CPW (Coplanar waveguide) fed monopole antenna, whose radiation patch is a bended metallic patch. We choose the suitable shape and size of the ground plane to achieve impedance matching. By adjusting and optimizing the parameters of the proposed antenna, the relative bandwidth is achieved to 9.3% and 46.5% respectively, which satisfy broadband and dual-band requirements of WLAN antenna.A CPW fed T-shaped monopole antenna is also designed in the literature. In order to improve the dual frequency performance, a parasitic rectangle patch is added into the back of the antenna. There are several advantages for the proposed antenna, such as compact structure, wide operation bandwidth, and good omni-directional radiation patterns. Hence the proposed antennas satisfy the requirements of WLAN applications.