PRINTED UWB ANTENNA FOR WIMAX /WLAN

Strong subscriber growth over the past year has demonstrated the appeal of WiMAX technology ( WiMAX-1 & WiMAX-2) . The IEEE 802.16 working group has been established a new operating band name as Worldwide Interoperability for Microwave access (WiMax). WiMax has three allocated frequency bands. The low band (2.5-2.69 GHz), the middle band (3.2-3.8 GHz) and the upper band (5.25.8 GHz). Printed antennas are attractive because their uniplanar architecture which helps to integrated with active devices or MMIC easily. In this paper, a printed small antenna fed by a microstrip line with a rotated square for bandwidth enhancement is proposed and discussed. Field distribution, gain and Impedance characteristics of this antenna are presented and discussed. A simple 50 ohm microstrip line is used to excite the slot. A rotated square slot resonator is considered as reference geometry. By embedding a parasitic patch into the center of the rotated square slot, the lower resonant frequency is decreased and the higher resonant frequency is increased. The measured results demonstrate that this structure exhibits a wide impedance bandwidth, s11 < -10 which is over ranging from 2.84 to 6.19 GHz. The parametric analysis of the antenna is done by using Method of Moment based available electromagnetic solver IE3D.