A compact CPW fed modified circular patch antenna with stub for UWB applications

In this paper, a new coplanar waveguide CPW fed Modified Circular Patch Antenna (MCPA) is presented. The proposed antenna is designed to operate from 3 GHz to 12 GHz. It consists of a circular patch which is truncated from two sides with respect to feed line. A stub of optimized dimension is attached to other side at a proper location to achieve ultra wide band characteristics. The proposed antenna is printed on a dielectric substrate glass epoxy FR 4 substrate and fed by a 50 Ω CPW on the same layer, which can yield an ultra wide bandwidth (-10 dB reflection coefficient) with satisfactory radiation patterns. The radiation patterns in the x-z plane are relatively omnidirectional, whereas the y-z plane patterns are bidirectional similar to that of a monopole antenna. The performance and characteristics of the antenna are investigated in order to understand its operation. It is proposed that this antenna can be part of various ultra wideband communication systems.