Evaluation of the Relative MIMO Gain

This paper shows some results for the relative MIMO capacity (compared with a SISO system) with respect to the number of antennas, antenna orientation and distance. The MIMO capacity is extracted from the Geometrically Based Single Bounce Channel Model, where the channel is modelled by propagation in an environment composed of clusters of scatterers. The results are shown for the pico-, microand macro-cell environments. For picoand micro-cells, an increase in the number of antennas has a larger impact on capacity gain than the one for macro-cells. For micro-cell scenarios, a 20% variation in performance is obtained, depending on the orientation of the antennas of both transmitter and receiver. For the macro-cell, a similar variation is seen, but only for the orientation of base station antennas. For picoand micro-cells, the relative MIMO gain is very similar for both upand downlinks. The gain increases from macroto pico-cell scenarios, ranging from 1 to 8.