A Joint Resource Allocation Scheme for Relay Aided Uplink Multi-User OFDMA System

In this paper, we study the problem of resource allocation in orthogonal frequency division multiple access (OFDMA) based multi-user dual-hop uplink transmission where a single relay station is deployed between the mobile users and the base station which operates under amplify-and-forward (AF) relaying mode. The optimization targets to maximize the overall system throughput through joint optimization of sub-carrier allocation, sub-carrier pairing, and the power allocation, subject to individual power constraint at each node. The optimization results in mixed integer programming problem and a near optimal solution is obtained through dual decomposition approach. Further, we develop a suboptimal scheme to trade the performance for lower complexity. Finally, numerical examples are provided to demonstrate the performance gain of the proposed schemes.