Interference Aware Relay Assignment Schemes for Multiuser Cognitive Radio Systems

In this paper, we present two low-complexity interference aware multiple relay assignment schemes for cognitive radio systems. The main objective in assigning multiple relays is to maximize the sum capacity of the cognitive radio system under the constraint of acceptable interference to the primary users (PU). The computational complexity of finding an optimal assignment by exhaustive search grows exponentially with the number of relays and users. The proposed schemes have low computational complexity, and their effectiveness is verified through simulation results.