Spectral and energy efficiency for massive MIMO systems using exponential correlation model

Abstract

The use of massive multiple input multiple output (MIMO) systems can improve the performance of energy efficiency and increase the capacity limits due to the improvement of the spatial correlation. The effect of the exponential correlation model on the massive MIMO energy and spectral efficiencies is investigated using a base station (BS) with a large number of antennas and a single antenna user terminal. To generate the lower capacity bounds, we used least minimum mean square error (LMMSE) as a pilot based channel estimator for the uplink channel. Different scenarios are implemented by using several numbers of BS antennas and changing the signal to noise ratio (SNR) values. The spectral efficiency was more sensitive to the change of the correlation factor when using higher SNR. It is shown that for the higher number of BS antennas we have, more energy efficient performance we get.