A Five-Port Integrated Planar Ultra Wideband and Narrowband Antennas System Using Excitation Switching Reconfigurable Technique for Cognitive Radio Applications.

This work presents an integrated planar five-element antennas system for cognitive radio (CR) applications.The proposed system is composed a UWB antenna for sensing the radio spectrum and four different NB antennas for conducting the communication tasks. The overall antenna system is printed on FR-4 substrate of 50 mm × 50 mm × 1.6 mm dimension. The UWB antenna-coupled at port 5 (P5) is designed for sensing the 3.1 GHz to 10.6 GHz un-licensed UWB band. The first NB antenna attached to port 1(P1) covers 5 GHz to 11.4 GHz wideband frequency, whereas the paired NB antennas located at port 2 and port 3 (P2 & P3) consists of two similar antennas to achieve MIMO operation and provides 3.05 GHz to 3.75 GHz and 4.9 GHz to 6.1 GHz dual-band operation. The last NB antenna accessible at port 4 (P4) operates in dual-band frequencies of 3.7 GHz to 4.92 GHz and 8.3 GHz to 11.3 GHz. These attained resonant bands cover applications, notably Wi-MAX 3.5 GHz, Upper WLAN, sub 6 GHz 5G, and X-bands in the full UWB spectrum. The minimum isolation among all UWB and NB antennas is 16 dB over the working bands. The MIMO performances of the port 2 and port 3 antenna pairs have been computed considering the envelope correlation coefficient and mean effective gain, and found within their practical limits. The measured results are validated and show a good matching with the simulated ones. The low profile and planar features of the suggested antenna make it a possible choice to be assimilated within small wireless devices applicable in CR communication. [ABSTRACT FROM AUTHOR]