Radio Unit Configuration for Dynamic Time Division Duplex in Distributed MIMO Systems

In this paper, a novel radio unit (RU) uplink (UL)/downlink (DL) configuration algorithm for dynamic time division duplex (DTDD) distributed multiple-input multiple-output (D-MIMO) systems with half-duplex RUs is proposed, where the configuration is performed only by the long-term channel statistics without the knowledge of instantaneous channel state information (CSI). Although there are several RU configuration approaches based on instantaneous CSI in the literature, a remaining challenge is to reduce the frequency of RUs UL/DL reconfiguration so as to lower the computational cost in the network and reduce the control signaling overhead in the fronthaul links. The proposed method is shown to be effective compared to the state-of-the-art methods in the trade-off between performance, complexity, and fronthaul overhead.