Investigating the diversity performance of multiuser spatially correlated MIMO broadcast fading channels

This paper's aim is to investigate the diversity performance of spatially correlated multiple-input multiple-output (MIMO) broadcast channels where multiple communications occur simultaneously in the same frequency band and time slot from the base station (BS) to many mobile stations (MS). To deal with a broadcast system we employ a previously developed orthogonal space division multiplexing (OSDM) method to decompose the channel into many uncoupled single-user systems so that the diversity can be readily characterized by the second-order statistics of the resultant channel coefficients. Simulation results reveal that good performance can still be achieved with correlation as high as 0.4. Most intriguingly, unlike single-user MIMO channels, the diversity is more sensitive to the spatial correlation (in the transmitter than receiver sides.