A Miniaturized inductive - Loaded narrow strip wide band-notched ultra-wideband monopole antenna with dual-mode resonator

A new miniaturized ultra-wideband (UWB) monopole antenna with a broad band, sharp roll-off frequency notch function is presented. A narrow, stepped impedance strip is the radiating element of the antenna similar to conventional narrowband antennas, in order to retain the conventional antenna characteristics such as polarization purity, omnidirectional radiation pattern, etc. The strip is split to create multiple closed resonances and inductors are loaded in series to achieve wide bandwidth. The split portions are inserted one over the other to make the antenna very compact. A new compact dual mode wide band parasitic resonator placed along the feed line, rejects the frequency band ranging from 5.15 to 5.825 GHz which has been allocated for IEEE 802.11a and High Performance Radio Local Area Network (HIPERLAN). The designed antenna was fabricated and the results were measured in an anechoic chamber. The measured results show the ultra-wideband resonance with reflection coefficient values below −10 dB over 3-10.5 GHz with a sharp roll off notch band.