Single and dual band-notched ultra-wideband antenna based on dumbbell-shaped defects and complementary split ring resonators

Printed ultra-wideband (UWB) monopole antennas are proposed with compact size and single/dual band-notched characteristics to prevent interference with nearby communication systems. It is shown that a dumbbell-shaped defect in the radiating element of a UWB monopole antenna can produce a notch band. The frequency of the notch can be easily adjusted by changing the physical dimensions of the defected structure. It is further shown that, a pair of complementary split ring resonators (CSRRs) embedded in the dumbbell-shaped defect can be used to produce a second notch. The proposed dual band-notched antenna can be used for the rejection of interference with Worldwide Interoperability for Microwave Access (WiMAX) systems covering the 3.3-3.6 GHz band, and either lower or upper wireless local area networks (WLANs) operating in the 5.15-5.35 GHz and 5.725-5.825 GHz bands, respectively.