Multi-cell cooperation (MCC) is an approach for mitigating inter-cellinterference in dense cellular networks. Existing studies on MCC performancetypically rely on either over-simplified Wyner-type models or complexsystem-level simulations. The promising theoretical results (typically usingWyner models) seem to materialize neither in complex simulations nor inpractice. To more accurately investigate the theoretical performance of MCC,this paper models an entire plane of interfering cells as a Poisson randomtessellation. The base stations (BSs) are then clustered using a regularlattice, whereby BSs in the same cluster mitigate mutual interference bybeamforming with perfect channel state information. Techniques from stochasticgeometry and large deviation theory are applied to analyze the outageprobability as a function of the mobile locations, scattering environment, andthe average number of cooperating BSs per cluster, L. For mobiles near thecenters of BS clusters, it is shown that as L increases, outage probabilitydiminishes sub-exponentially if scattering is sparse, and following a power lawwith an exponent proportional to the signal diversity order if scattering isrich. For randomly located mobiles, regardless of scattering, outageprobability is shown to scale with increasing L following a power law with anexponent no larger than 0.5. These results confirm analytically thatcluster-edge mobiles are the bottleneck for network coverage and provide aplausible analytic framework for more realistic analysis of other multi-celltechniques.
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