Design of slot loaded band-notched UWB antennas

Ultra wide-band (UWB) is the recently standardized method for short-range, peer-to-peer, ultra-fast communication. UWB frequency allocation in USA spans from 3.1 GHz to 10.6 GHz. As this range includes existing wireless communication frequencies (e.g. IEEE 802.11a WLAN) UWB coexistence with other systems has been an important issue. In this paper, filtering or notching out certain frequency bands from a UWB antenna by resonant slot loading is considered. A slot loaded UWB printed monopole antenna is presented. A simplified method, based on slot line theory, for predicting the frequency of the notched out band has been formulated. Simulated and measured reflection coefficient values have been obtained to assess the accuracy of the results predicted by the simplified method. A good agreement is observed