A novel reconfigurable broadband antenna for cognitive radio systems

Dynamic spectrum access based on cognitive radio systems is highly desired to satisfy the expanding wireless communication demand. However, cognitive radio is in need of a compact antenna that is capable of covering a large frequency range. In this paper, a novel reconfigurable broadband antenna is proposed, which is capable of a dynamic multiple channel access in the frequency range from 400 MHz to 4 GHz. The proposed antenna maintains the compact size so that it is suitable for mobile multiple-input-multiple-output (MIMO) applications. The antenna achieves a minimum −5 dB channel bandwidth of 33 MHz which is large enough for TV whitespace applications.