A simple and compact CPW-fed UWB printed monopole antenna with defected ground structures

摘要

A planar simple and compact monopole antenna for UWB applications is proposed with CPW feeding. The radiating patch of the antenna consists of a top-cut half-circle together with a triangle on the lower edge. The bottom side of the antenna includes a rectangular defected ground plane with two different symmetrical bevels. By cutting out these bevels on the ground plane, bandwidth coverage of the overall UWB range except 5.4–7 GHz frequency band is provided. To enhance input impedance bandwidth characteristics at 5.4–7 GHz frequency band, dimensions of the triangular part on the lower edge of the patch and top-cut half-circle part on the upper edge are optimized. The overall size of the proposed antenna is 22×20×1 mm³. Simulations are carried out using commercially available ANSYS's HFSS program which uses the finite element method (FEM). Results show that 110% of the impedance bandwidth between 3.6 and 12.2 GHz for VSWR<2 is achieved. Moreover, antenna has a stable omnidirectional pattern at XZ plane over the frequency band. Also, the presented antenna is fabricated on FR4 substrate and it is measured