Grouping algorithm for partner selection in cooperative transmission

The partner selection problem for cooperative transmission is considered. Our objective is sum power minimization. We provide a simple optimal rate allocation algorithm for two cooperating node pairs and closed-form optimal rate allocations for some cases. With these results, we determine the partner for each node pair by Gabow´s Algorithm. For a large number of nodes, we propose the grouping algorithm which is near-optimal but reduces the communication and computational overhead. We show the significant improvement of power consumption by our scheme and the fast convergence of the grouping algorithm through simulations