Energy-Efficient Multiuser MIMO Downlink Transmissions in Massively Distributed Antenna Systems with Predefined Capacity Constraints

Massively distributed antenna system is a promising architecture to enhance the system performance in future broadband wireless access beyond the Long Term Evolution (LTE) and Long Term Evolution Advanced (LTE-A) standards. Reduction of the power consumption of such systems is an important issue in their practical realization. This paper presents a technique to optimize the power consumed by a massively distributed antenna system in a multiuser downlink scenario subjected to throughput constraints. More specifically, the power consumed under the target sum-capacity constraint is optimized. We use zero-force beamforming scheme to simplify our analysis and derive optimal-rate allocation among the users. Simulation results confirm that the energy consumption can be reduced considerably while the throughput constraint is satisfied.