CPW-Fed Monopole Antenna with L Shaped and Stair Shape Slot for Dual-Band WLAN/WiMAX Applications

A novel dual-band design of a finite ground coplanar waveguide (CPW)-fed monopole antenna is presented for simultaneously satisfying wireless local area network (WLAN) and worldwide interoperability for Microwave Access (WiMAX) applications. The wireless communication industry is integrating a number of services like Bluetooth, WLAN etc to the hand held communication devices. Therefore, in the present scenario, the bandwidth requirement of the antenna while maintaining the compactness becomes more critical.
The proposed antenna, comprising a rectangular planar patch element embedded with two L shaped slots and stair shape slot in the middle of the patch element. The simulated-10 dB bandwidth for return loss is from 2.0 to 2.2 GHz and 2.8 to3.1 GHz, covering some of the WiMAX and WLAN bands. Prototypes of the obtained optimized antenna have been designed and constructed. The Antenna has 9.5% (-10 dB return loss) band width ranging from 2 to 2.2 GHz, and 21 dB return loss is from 2.85 to 2.95 GHz. The parametric study is performed to understand the characteristics of the proposed antenna. Also, good antenna performances such as radiation patterns and antenna gains over the operating bands have been observed and VSWR is 5.2 at 2.4 GHz. The radiation patterns in polar plot theta 90 & 150 degrees.