An optimized resource allocation algorithm in cooperative relay cognitive radio networks

Cognitive radio (CR) is an effective way to improve the utilization of spectrum resource. This paper focuses on the resource allocation in cooperative relay cognitive radio networks and proposes an optimized resource allocation algorithm. In the algorithm, when the channel between the primary source and destination is good, the primary user (PU) selects a best sub-channel to transmit its data directly, while secondary users (SUs) use the remaining idle sub-channels to transmit their own data. When the channel between the primary source and destination is poor, SUs work as the relays of the PU to cooperate the PU transmitting data. We study the joint optimization of sub-channels and power allocation to guarantee the transmission of PU and maximize the throughput of cognitive networks. Simulation results show that the optimized resource allocation algorithm proposed in this paper has about 20% advantage over conventional cooperative-relay resource allocation algorithm in the achieved rate.