Design and ground plane consideration of a CPW-fed UWB antenna

In this paper, a novel ultrawideband (UWB) antenna with co-planar waveguide (CPW) feed is presented. The antenna is based on an egg-shaped conductor printed on a 30×40 mm² FR4 substrate of 1.6-mm thickness. Two configurations of the antenna are studied. In the first, the ground plane features a large egg-shaped slot, and in the second, the ground plane is partial and rectangular in shape. The measured and computed return loss responses are given. Other characteristics of the antenna are computed using a finite-element-based EM solver. The radiation patterns, peak gain, and radiation efficiency of both configurations are presented and compared. The results show that the design based on the large slot yields better omnidirectional patterns and higher gains in the principal planes. The second design has slightly larger radiation efficiencies, and larger peak gains at high frequencies.