Fraunhofer Institute for Industrial Engineering
The authors develop an efficient relay selection protocol for two-hop transmission in cognitive radio networks where secondary users interfere with a primary user. Their protocol provides joint benefits of two well-known relaying strategies, namely relay sub-set selection and incremental relaying. It aims at minimizing the outage probability for delay-constrained applications by utilizing rate-less codes. The advantages of the proposed scheme compared to conventional relay selection protocols can be summarized as follows: feedback overhead is significantly reduced, resources are exploited efficiently, outage probability is minimized.