On the capacity of large-scale MIMO multiple access channels with linear receivers in UDNs

In this article, we investigate the capacity of large-scale multiple-input multiple-output (MIMO) multiple access channels (MACs) with linear receivers in ultra dense networks (UDNs) where the number of antennas at the base station and the number of total interfering terminals approach to infinity while maintaining a fixed ratio. To study the multicell uplink capacity of a large-scale MIMO system, we first find the probability distribution of the post-processed signal to interference and noise ratio (SINR) using large dimensional random matrix theory without the limiting condition that the channel vectors between users orthogonalize in the large-scale MIMO system in contrast to previous work. Then modeling the practical 2-D UDN topology, we analyze which factors affect the capacity of large-scale MIMO MACs in UDNs. Finally, simulation results verify our analytical results and demonstrate a comparison on the capacity between three user equipment (UE) distribution models.