Abstract
A cognitive radio antenna integrated with narrow /ultrawideband (UWB) antenna is described in this paper. The proposed antenna consists of two port-fed wide-slot antennas sharing the same substrate. The proposed ultra-wideband (UWB) antenna which covers the entire UWB band from 3.1 GHz to 10.6 GHz is used for channel sensing. The integrated, narrowband wide-slot antenna, operating in the range of 8.2 GHz to 11.0 GHz is designed to communicate with other wireless devices. The reconfigurable function is realized by utilizing ideal switches. The isolation between the two ports is better than -10 dB. The design is suitable for cognitive radio applications where the UWB antenna is required for spectrum sensing and the narrow band antenna is used for reconfigurable operation, which can be tuned over a wide bandwidth by changing the dimensions of the triangular radiation patch using ideal ON/OFF switches.