Joint User Grouping and Resource Allocation for Multi-User Dual Layer Beamforming in LTE-A

In TD-LTE-A system, dual layer beamforming is introduced to improve throughput of specific users with high SINRs. In order to solve the problem of resource allocation for multi-user dual layer beamforming, a low complexity joint user grouping and resource allocation algorithm is proposed in this letter. We first calculate priorities of all active users according to channel quality and then the resource block (RB) corresponding to the user with highest priority is decided. After that, other users allocated to the above RB are selected based on our proposed user grouping method which considers both inter-user interference and channel quality. The process repeats so that inter-user interference can be reduced and system throughput can be improved. Simulation results show that high system throughput can be realized with the proposed algorithm and the fairness requirement can also be satisfied.