DESIGN OF NOVEL WIDEBAND MONOPOLE ANTENNA WITH A TUNABLE NOTCHED-BAND FOR 2.4 GHZ WLAN AND UWB APPLICATIONS

In this article, a novel wideband planar monopole antenna for applications in 2.4 GHz WLAN and UWB bands is presented and investigated. The proposed antenna is composed of a gourd-like radiation element fed by a 50 Ohm microstrip line and a step-shaped ground plane. A pair of slot lines is etched symmetrically on the ground plane to obtain the 5 GHz band-notched characteristic, and the notched band can be tuned. The proposed antenna is successfully simulated, designed, and measured. The measured results agree reasonably with the simulated ones. According to the measured results, the proposed antenna yields a wide bandwidth ranging from 2.2 to 11 GHz for VSWR less than 2, except the notched band of 5.1-6.2 GHz for 5 GHz WLAN. Moreover, it exhibits nearly omnidirectional radiation patterns, stable gain, and small group delay variation across the operation band, which meets the requirements of 2.4 GHz WLAN and UWB applications.