In this paper the spatial distribution of the channel capacity of Multiple Input Multiple Output (MIMO) wireless systems within a microcell scenario is studied. Based on the capacity location dependency, made clear by realistic simulation results, a segmentation of the cell area into high and low capacity regions is proposed. The Base Station (BS) and Mobile Stations (MSs) inter-antenna spacing impact on these regions is also investigated. The results suggest the most efficient ways to enlarge the high capacity region, providing a framework to optimize the design and deployment of MIMO systems.