Dual band-notched tapered slot antenna using λ/4 band-stop filters

This study proposed a novel quarter-wavelength band-rejected element for band-notched antennas. It consists of a metal via and a rectangular strip connected to the radiating patch. In order to validate the design, a dual band-notched elliptically tapered slot antenna for ultra-wideband (UWB) applications is designed using the loaded strips. This antenna is capable of filtering the coexistent WLAN802.11a frequency bands 5.15-5.35 and 5.725-5.825-GHz. Compared with other band-notched UWB antennas, this antenna features the merit of easy tuning of each rejected frequency band because of the low mutual coupling between loaded strips at rejected frequencies. Both simulated and measured results confirm that the proposed antenna is able to achieve a wide bandwidth from 3 to over 11-GHz with two unwanted frequency bands notched. Stable radiation patterns are observed across the operational frequency range, with cross-polarisation levels below -20-dB.