Coplanar waveguide-fed slot antenna for wireless local area network/worldwide interoperability for microwave access applications

Owing to the recent demand to incorporate the two communication services, the wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX), therefore dual-band antennas that are designed with sufficient bandwidths to cover both WLAN and WiMAX operating bands are presently very important topics of research. Owing to the difficulty of simultaneously achieving both compactness and wideband, the dimensions of most dual-band slot antenna designs that are reported in recent literature exceed 35 x 40 mm(2). Therefore this study presents a compact (32 x 32 mm(2)) coplanar waveguide (CPW)-fed slot antenna design with dual-band operation for WLAN (2.4/5.2/5.8 GHz) and WiMAX (2.3/2.5/3.5/5.7 GHz) applications. To achieve wide 10 dB bandwidth for the lower operating band (58%), the technique of applying a square-ring slot antenna type with an asymmetric ground plane was used herein, and a broad upper operating band (32%) was attained by introducing a stub-protruded monopole and loading a double-bent stub into one of the asymmetric CPW ground planes. The process of designing the proposed antenna is explicitly shown, and parametric studies were carried out by simulation. Typical experimental measurements were also conducted and compared with the simulated results.