Coverage and rate in cellular networks with multi-user spatial multiplexing

In this paper we consider a multi-user spatial multiplexing (SM) cellular network, where N_t streams are transmitted to N_t users in the cell. Specifically, we obtain the coverage and rate expressions for a system employing zero-forcing (ZF) receiver. Compared to single stream transmission (SST), it is interesting to see that SM degrades the rate for a notable percentage of users. For the case of two and four receiver antennas, the increase in mean rate of SM is modest compared to single stream transmission (SST) while SST provides a gain over SM for cell edge users.