Radio resource allocation for cooperative relay-assisted OFDMA wireless networks

This paper considers a wireless cooperative OFDMA network with a base station and some relays. The relays adopt the decode-and-forward protocol and can assist the transmission from base station to mobile stations. The objective is to maximize the system transmission rate of downlink under various constraints. The optimal solution for such radio resource allocation problem has high computational complexity. Thus we divide our solution scheme into three steps. The first step is to select the relay that can achieve best transmission rate. Then the subcarrier is distributed to the selected relays. For each hop, the same subcarrier should not be used. Next, power allocation is adopted under the individual power constraints for each node. Simulation studies are conducted to evaluate the system performance. It confirms that our proposed algorithm can enhance the performance compared with newly proposed resource allocation schemes.