Energy Efficient Power Allocation for Multi-User MIMO Downlink Systems with Statistical Delay Constraints

In this paper, we propose an energy efficient power allocation algorithm to maximize the energy efficiency (EE) of downlink multi-user multiple-input multiple-output (DL MU-MIMO) systems under the individual delay-quality of service (QoS) constraints. Using the novel performance metric, effective-EE, which takes into account the impact of delay outage, we can formulate effective-EE maximization problem with the delay-QoS constraints as a power allocation problem. By applying Lagrangian method, we can solve optimization problem and propose the power allocation algorithm. Simulation results demonstrate that our proposed algorithm can improve the effective-EE performance for MU-MIMO downlink systems.