A miniaturized triple band-notched UWB antenna

In this study, a compact microstrip-fed ultra-wideband (UWB) monopole antenna with triple band-notched characteristics is presented. UWB bandwidth is achieved through tapering of both the radiating element and the transmission line. A single parasitic microstrip resonator on the backside of the radiator is introduced to realize filtering at WiMAX (3.5 GHz) and WLAN (5.25, 5.775) bands. The microstrip resonator having dimensions of 8.2 mm x 8 mm is made up of three L-shaped strips inside a C-shaped strip. The overall size of the antenna is very compact 12 x 18 mm(2). The antenna provides sharp cut-offs in the notched-bands to conserve all the useful frequencies within the ultra-wideband. Measured impedance-bandwidth of the antenna is 3.1-11.5 GHz for voltage standing wave ratio (VSWR) <2 except for the notched-bands 3.4-3.6 GHz, 5.15-5.39 GHz, and 5.75-5.96 GHz. The antenna is also analyzed for far-field characteristics and a good agreement is found between simulated and measured results.