An Energy-Efficient Framework for the Analysis of MIMO Slow Fading Channels

In this paper, a new energy-efficiency performance metric is proposed for multiple-input multiple-output (MIMO) point-to-point systems. In contrast with related works on energy-efficiency, this metric translates the effects of using finite blocks for transmitting, using channel estimates at the transmitter and receiver, and considering the total power consumed by the transmitter instead of the radiated power only. The main objective pursued is to choose the best precoding matrix used at the transmitter in the following two scenarios : 1) the one where imperfect channel state information (CSI) is available at the transmitter and receiver and 2) the one where no CSI is available at the transmitter. In both scenarios, the problem of optimally tuning the total used power is shown to be nontrivial. In scenario 2), the optimal fraction of training time can be characterized by a simple equation. These results and others provided in the paper, along with the provided numerical analysis, show that the present work can therefore be used as a good basis for studying power control and resource allocation in energy-efficient multiuser networks.