Joint Resource Allocation for Multi-User and Two-Way Multi-Relay OFDMA Networks

In this paper, we investigate a joint subcarrier- relay assignment and power allocation scheme for amplify-and- forward (AF) based two-way multi-relay networks. We formulate a sumrate maximization optimization problem with individual power constraints on each node. The target is to seek a unified optimalscheme for subcarrier-relay assignment and power allocation. The problem turns out a mixed integer nonlinear programming problem (MINP), which can be asymptotically solved through Lagrange dual decomposition method (DDM). To evaluate the contradictory of performance and computational complexity, we propose a low complexity suboptimal algorithm to trade off between performance and complexity. Finally, Simulation results are presented to demonstrate the performance of the proposed algorithms.