Abstract
The design of a printed compact planar antenna of asymmetrical structure with ultra wide bandwidth is described and investigated in this paper. The antenna provides more than 114% impedance bandwidth below VSWR 2 (from 3.3 to more than 12 GHz) with a center frequency of 7.65 GHz; thus it covers the bandwidth requirement for portable UWB wireless device applications. The structure of the asymmetric proposed antenna is very simple and composed of a small hexagonal shaped patch with two asymmetrical coplanar ground planes. It occupies an area of only 20 x 24.5 mm(2) when printed on one side of an FR4 substrate with a thickness of 1.6 mm.