A cooperative cognitive radio network using smart antenna

In this paper, a cooperative communication scheme using smart antenna is proposed for cognitive radio networks. This scheme expands the concept of cognitive radio in time and space. Using the cooperation, spectrum sensing accuracy and throughput of cognitive radio networks can be observably increased. The licensed users´ detection and unlicensed users´ transmission are almost carried on simultaneously. The beamforming of smart antenna can help cognitive radio networks to reduce the interference to licensed users and acquire antenna array gain for unlicensed users. The performance characterizations reveal that the scheme has lower outage probability and more accurate primary detection than general CR networks.