Exploiting opportunistic decode-and-forward cooperation for cognitive radio relay channels in multi-antenna cognitive radio networks

In this paper, we investigate the performance of an opportunistic decode-and-forward cooperation (ODFC) strategy for cognitive radio relay channels (CRRCs) in multi-antenna cognitive radio network. The key feature of the proposed strategy is that, via opportunistically decode-and-forward cooperation strategy, the cognitive users can maximize its end-to-end throughput by utilizing opportunistic cooperation. The proposed ODFC strategy maintains full diversity. Simulation results demonstrate the effectiveness of the proposed approach as compared to no power no channel allocation scheme (NPNCA), power allocation scheme (PA), and channel allocation scheme (CA). Opportunistic cooperation significantly improves the end-to-end throughput of the system and performs very close to channel allocation scheme in single antenna case and increases the end-to-end throughput in multi-antenna case without using additional transmit power or bandwidth requirement.