Joint Beam Management and User Scheduling for Massive MIMO with Hybrid Beamforming and Limited Feedback

In this paper, we consider the design of multiuser (MU) massive multiple-input and multiple-output (MIMO) employing hybrid beamforming, i.e., an analog radio frequency (RF) beamforming at the front end concatenated with a digital baseband precoding. We present several RF beam feedback protocols with small overhead, i.e. the RF beam indices with or without channel quality index (CQI). Based on the beam feedback schemes, we design novel algorithms to jointly select the transmit RF beams and schedule the users to improve the system throughput. Specifically, when the users feed back multiple candidate RF beams, the new algorithms resolve the conflicts when different users feedback some same RF beams. The simulation results demonstrate the efficacy of the proposed algorithms.