Stochastic geometric modeling and interference analysis for massive MIMO systems

We study a multiple input multiple output (MIMO) cellular system where each base-station (BS) is equipped with a large antenna array and serves some single antenna mobile stations (MSs). With the same setup as in [1], the influence of orthogonal and non-orthogonal pilot sequences on the system performance is analytically characterized when each BS has infinitely many antennas. Using stochastic geometric modeling of the BS and MS locations, closed-form expressions are derived for the distribution of signal-to-interference-ratio (SIR) for both uplink and downlink. Moreover, they are shown to be equivalent for the orthogonal pilots case. Further, it is shown that the downlink SIR is greatly influenced by the correlations between the pilot sequences in the non-orthogonal pilots case. Finally, the mathematical tools can be used to study system performances with other general channel estimation methods and transmission-reception schemes.