Resource Allocation In Cellular Relay Network Based OFDMA

Introduce the relay technology into traditional cellular network, it can expand the traditional cellular network coverage area, improve the system throughput. Relay technology has introduced into LTE-Advanced and WiMAX. OFDMA is the evolution of OFDM, it can eliminate inter-symbol interference and improve the spectrum utilization. The combination of relay and OFDMA is a trend of future mobile communication network. This paper focuses on the radio resource allocation on the OFDMA cellular relay network.First of all, this paper elaborates the cellular relay network architecture, the key technologies of the relay node and discusses the algorithms of relay selection. Introduce relay node into traditional cellular network can overcame the near-far effect in the wireless communication system, due to scarcity of frequency resources, the future mobile communication will use the carrier higher than 2GHz, the transmission of the high carrier can be seen NLOS, therefore the near-far effect still exists in cellular relay system. Base on existing resource scheduling algorithm, the optimal resource allocation scheme is formulated to protect the users rate fairness, however it is difficult to find the optimal solution for its computational complexity. So this paper proposes a sub-optimal algorithm, simulation results show that this algorithm can enhance the user rate fairness and guarantee the system throughput. Moreover, The match problem of capacity between the backhaul link and access link in the relay node affect the cellular relay system performance directly, meanwhile introduce the relay node into the cellular network make the interference between the same frequency channel is more complex, this is serious impact on the throughput of the system, this paper propose an power allocation algorithm to coordinate inter-cell interference, the algorithm combine Tabu search algorithm and non-cooperative game theory, it can enhance the throughput of access link of relay node for non-cooperative game theory, the Tabu search can match the capacity between backhaul link and access link. Simulation result shows the proposed algorithm can improve the throughput and reduce the node transmission power.