  Power consumption is one of the major issues in massive MIMO (multiple input
multiple output) systems, causing increased long-term operational cost and
overheating issues. In this paper, we consider per-antenna power allocation
with a given finite set of power levels towards maximizing the long-term energy
efficiency of the multi-user systems, while satisfying the QoS (quality of
service) constraints at the end users in terms of required SINRs
(signal-to-interference-plus-noise ratio), which depends on channel
information. Assuming channel states to vary as a Markov process, the
constraint problem is modeled as an unconstraint problem, followed by the power
allocation based on Q-learning algorithm. Simulation results are presented to
demonstrate the successful minimization of power consumption while achieving
the SINR threshold at users.
