Estimated capacities for a multiple input multiple output system based on outdoor to indoor channel measurements

In this paper we estimate the channel performance in terms of ergodic and outage rates based on measured channels in a university campus type of environment. The characteristics of the channels we measure are: (4 times 4) MIMO (multiple input multiple output) single user channels with non line of sight, outdoor to indoor, having wide bandwidths for fixed wireless applications (e.g., high speed Internet wireless). The striking result of this analysis is that even though we have estimated that our measured MIMO channels have uncorrelated matrix elements there is a significant decrease in performance for the case of no channel knowledge at the transmitter in terms of outage rates with respect to the outage rates of iid Rayleigh channels of the same order. We find that this is due to shadowing effects that cause a variation in the received SNR generating a significant increase in the lower tail of the pdf of the channel capacity.