A Compact Notched Band UWB Slot Antenna With Sharp Selectivity and Controllable Bandwidth

A compact ultra-wideband (UWB) slot antenna with band-notched characteristics is proposed. A stepped slot is adopted as a radiator to realize UWB impedance matching and reduce the antenna size. By slitting an open-ended quarter-wavelength split slot on the back of the feed and a short-ended half-wavelength split-ring slot near the stepped slot, a second-order notched band of 5.15-5.85 GHz is achieved. Compared with the traditional band-notched antenna, the selectivity of the notched band is greatly improved and size of the antenna is reduced at the same time. The volume of the antenna is only 22 mm×8.5 mm×0.8 mm. Besides, the bandwidth can be easily controlled by adjusting the lengths of the two slots respectively. Good agreement is achieved between simulated and measured results, which show that the proposed antenna has nice impedance matching and radiation pattern characteristics.