Miniaturization of Printed Elliptical Disc Monopole Antennas for UWB Applications

In this paper, we describe improved designs of a printed disc monopole antenna for UWB application, focusing on miniaturization of the disc radiator with the size of the ground fixed. In order to decrease the antenna size, an exponentially curved notch on the ground plane of the antenna was investigated, and the optimal design of the shape of notch verified. By appropriately adjusting the size of the notch, the VSWR characteristics of the antenna clearly can be improved. Our investigation has shown that the diameter of the circular radiator can be reduced to 15 mm by using the exponentially curved notch. The antenna has a nearly omnidirectional radiation pattern, like a traditional monopole. These features are very attractive for UWB applications.