The achievable sum rate of large-scale fading in multi-pair AF massive MIMO systems

Abstract

A multi-pair amplify-and-forward (AF) MIMO system is considered in this paper, in which all source users transmit their information to destination users via a shared relay. With the large N regime, the effect of small-scale fading tends to diminish while the large-scale fading plays a main role in affecting the system performance. The large-scale fading is modeled as generalized-K fading. While the achievable sum rate is investigated for three power-scaling schemes where the Minimum Mean-Square Error (MMSE) algorithm is adopted at the relay with perfect channel state information (CSI). The large-scale fading parameter can influence the system performance to some degree according to our analysis. Simulation results help to assess the accuracy of our analytical expressions.