Wideband Monopole Antenna With Three Band-Notched Characteristics

A configuration of multiband and compact ultrawideband (UWB) antenna is present. The antenna is printed on a dielectric substrate and fed by microstrip line. The dimensions of square slots etched into the microstrip feedline can be used to tune the antennas' band-notch and bandwidth characteristics. This antenna is designed to cover the bandwidth for UWB applications (3.1-10.6 GHz) with a VSWR lower than 2 and provide sufficient rejection band notches for WiMAX (3.3-3.88 GHz), WLAN (4.96-6.23 GHz), and ITU (7.9-8.7 GHz). A better gain pattern is realized by inserting slots in the microstrip feedline, compared to the defected structure. Furthermore, by the analysis of the current distribution on the antenna surface, we can deduce the equivalent circuit of the antenna.