Energy-Efficient Multi-Cell Massive MIMO Subject to Minimum User-Rate Constraints

The capability of massive multiple-input multiple-output (mMIMO) systems supporting the throughput require-ment of as many users as possible is investigated. The bottleneckof serving small numbers of users by a large number oftransmit antennas in conventional mMIMO is unblocked by anew time-fraction-wise beamforming technique, which focusessignal transmission in fractions of a time slot. Based on this time-fraction-wise signal transmission, a new user service schedulingfor multi-cell mMIMO, whose cell-edge users suffer not only poorchannel conditions but also multi-cell interference, is proposedto support a large user-population. We demonstrate that thenumbers of users served by our multi-cell mMIMO within atime-slot may be as high as twice the number of its transmitantennas.