Ultra-wideband star shaped planar monopole antenna

Abstract

A novel design of ultra-wideband star shaped printed monopole antenna is proposed. A star shaped structure is realized by combining triangular shaped planar monopole patch with its inverted configuration. A detailed parametric study of the offset placement of two triangular shaped patches with respect to the patch centroids, variation in distance between the base of composite structure and the ground plane, is presented. To further improve impedance matching composite structure is chopped at the lower vertex point and a parametric study for the offset feed positions is carried out. The proposed antenna yields an optimum bandwidth of more than 8 GHz ranging from less than 2 GHz to more than 10 GHz with a broadside co-polar gain of around 1 to 2 dBi over a complete bandwidth.