Downlink interference analytical predictions under shadowing within irregular multi-cell deployments

This paper describes a new analytical model based on stochastic geometry, which predicts the Inter-cell Interference (ICI) level suffered by User Equipments (UEs) in downlink (DL) Heterogeneous Networks (HetNets) according to their locations. The HetNet is modeled with stochastic geometry. More specifically, the proposed model relies on the Poisson Point Process (PPP) formalism (and its large arsenal of tools) to derive closed forms for location-dependent ICI under realistic propagation channel assumptions, including both fast fading and shadowing. Since the ICI level depends on the deployment type, both cochannel allocation and a separate frequency band allocation are investigated. Analytical models are thus derived for/regarding the median value of the co-channel interference and the cotier interference. The latter predictions are used to build 2D interference maps (i.e. with estimated ICI level at each pixel of the area of interest), which could be subsequently beneficial to location-based Radio Resource Management (RRM) or ICI coordination/cancellation algorithms in a real system. We provide herein a few illustrations in LTE-Advanced (LTE-A) standardcompliant scenarios, while discussing the “spatial reliability” of this model depending on key input parameters and working assumptions.