Maximum ratio transmission for massive MIMO: Non-asymptotic analysis with limited CSIR

This paper analyzes the performance of maximum ratio transmission (MRT) precoding in a massive MIMO interference channel operating in a time-division-duplex mode, where receivers have no channel state information (CSI) except for the average of their effective channel gains. The CSI error vector, inter-user interference vector resulting from MRT precoding, and Gaussian noise vector represent the total noise vector at each receiver whose covariance matrix can be computed. By noting that the total noise vector is neither Gaussian nor uncorrelated with the signal of interest, lower bounds can be obtained based on a worst-case uncorrelated Gaussian noise argument. The bounds hold for an arbitrary number of receivers and receive antennas with full-spatial multiplexing. Simulation results verify the validity of the obtained bounds.