In the future, mobile handsets might incorporate more than 20 separate radios, creating a difficult antenna design problem due to the sever space restrictions. This paper proposes a reconfigurable wideband antenna, for use within clamshell mobile handsets. The impedance bandwidth of the new antenna was selected in order to meet current and future demands within the industry. It has been suggested that a portable Cognitive Radio must be capable of simultaneous communication (via a narrowband antenna) and spectrum sensing (via a wideband antenna). For this reason a narrowband slot antenna has also been integrated within the wideband radiator.
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