The dynamics of user channels in massive MIMO systems

Abstract

The SNR associated with the different users in large-scale MIMO systems depends on the magnitude of the eigenvalues of the channel power matrix HH H. While it is known that the spread between the best and worst channels is reduced when the number of antennas N at the BS grows, there is little known about how these channels change due to the user mobility. Do all parallel channels change at the same rate, or conversely is their dynamic behavior different for the best and worst channels? We evaluate the interplay between the number of BS antennas N and the number of (single-antenna) users K in MIMO systems, and investigate the effect of letting N grow on the dynamics of the best and worst channels in this multiuser set-up.