Cluster-Based Dynamic DL/UL Reconfiguration Method in Centralized RAN TDD with Dense Deployment of Remote Radio Units

In this paper, we propose and evaluate a novel cluster-based dynamic downlink/uplink reconfiguration method in centralized TDD networks with dense deployment of remote radio units. All cells of interest are first divided into disjoint cell clusters with adequate geographical isolations. Cells within the same cluster would be allocated the same downlink/uplink configuration to avoid the cross-subframe co-channel interference. Transmission directions in cells belonging to different clusters could be different in a subframe by selecting different downlink/uplink configurations freely, in order to achieve the benefits of traffic adaptation. The central control units of the network optimize and reconfigure the downlink/uplink allocations on the basis of cell cluster. The optimization/reconfiguration accounts for both the traffic condition and the capability of cells, transmission directions and users in handling traffic demands. System level simulation results are provided, from which, the effectiveness of our proposed scheme is validated in terms of the cell- average and cell-edge packet throughput performances in both downlink and uplink directions.