Channel allocation for a three-node cooperative cognitive radio network

Channel allocation for a three-node cooperative cognitive radio network exploiting amplify-and-forward protocol (AF) is investigated in this paper. An optimal and a suboptimal channel allocation method were proposed in this paper. The optimal method is presented by picking the combination of channels that maximizes the system throughput. Comparing with the optimal method, the suboptimal algorithm reduced the computational complexity from O(4^N) to O(N) by allocating relay channels iteratively with minor performance loss. Numerical results show that the system throughput is enhanced by channel allocation, and the relay channels are allocated as direct transmission channels with a ratio of 1/3. It also shows that relay channels are hardly allocated as dual-hop channels. The computation complexities of both algorithms are demonstrated by comparing simulation time.