A compact UWB antenna with sharp band-notched characteristics and controllable notched bandwidth

A compact Ultra-Wide Band (UWB) antenna with sharp band-notched characteristic and controllable notched bandwidth is presented. The band-rejected structure is realized by inserting two half wavelength C-shaped slots with the same resonant frequency in the radiator. The two C-shaped slots couple together to form a sharp band rejection. A good impedance matching is obtained in 3.1-10.6 GHz frequency range(|S11|<;-10 dB), except the lower WLAN band of 5.15-5.35 GHz (|S11| >;-5 dB). Moreover, the band-notched bandwidth can be controlled by adjusting the dimensions of the two C-shaped slots.