Investigation of Multiple Antennas in Cooperative Cognitive Relay Network

Cooperative Cognitive Relay Network (CCRN) is a system that is used in Cognitive Radio Network (CRN) to improve the spectrum utilization in which Primary Users (PUs) exploit some Secondary Users (SUs) to relay the primary traffic cooperatively. The PU needs to give out a portion of channel access time to the selected SUs for transmitting secondary data in exchange for cooperation. The analyses for the primary and secondary transmission rate are evaluated using multiple antennas at SUs. Moreover, enhancement the throughput of the primary link is done by showing the effect of increasing the number of SUs and using different types of antennas. Optimum parameter will be investigated under using multi antennas to improve the performance of PUs and SUs. This parameter is the distance between antennas at SUs which is not clarified until now in this system. The simulation results show that by exploiting multiple antennas in CCRN, the transmission rates of both PUs and SUs can be significantly improved.