Abstract
In this article, ultra-wideband (UWB) monopole antenna with circular polarization (CP) is designed and implemented. The proposed antenna consists of an asymmetric shaped radiator fed by a microstrip line and a limited ground plane on the back side of the substrate. The overall size of proposed antenna is 28 mm × 29 mm, which is suitable for mobile devices. The antenna is fabricated on inexpensive FR4 a dielectric constant of, loss tangent tan = 0.019 with thickness of 1.6-mm. The measured results show that the proposed monopole antenna has a very wide bandwidth from 2.98 to 10.93 GHz that covers the UWB application range and defined by 10-dB return loss. Furthermore, a very wide CP bandwidth of 3-dB axial ratio bandwidth that ranges from 7.18 to 10.01 GHz is achieved. © 2012 Wiley Periodicals, Inc.