Mutual Information of Multiple-Input Multiple-Output (MIMO) Transmission Schemes

摘要

We analyze the mutual information of some common multiple-input multiple-output (MIMO) transmission schemes. Whereas most capacity evaluations are done under the assumption of Gaussian transmit symbols, we take into account restrictions on the transmit symbol alphabet and analyze real world signal constellations. Moreover, we include suboptimum detectors which might be applied in practical systems in the capacity evaluation. Furthermore, we consider not only spatially uncorrelated full rank channels but also channel degradations such as spatial correlation and keyhole effects. The results show that in many practical relevant cases, simple space-time block codes are a robust solution which achieves similar, sometimes even better capacities than spatial multiplexing even though they do not exploit all available MIMO dimensions.