A New Clustered HetNet Model to Accurately Characterize User-Centric Small Cell Deployments

Abstract

This paper develops a comprehensive framework for the performance analysis of user-centric capacity-driven small cell deployments, where small cell BSs (SBSs) are deployed at the places of high user density, i.e., user hotspots. In order to incorporate the correlation between user and SBS locations, we model the geographical centers of user hotspots as a homogeneous Poisson point process (PPP) around which users and SBSs are clustered following two independent general distributions. The macrocell base station (BS) locations are modeled by an independent PPP. A key intermediate step of our analysis is the derivation of a new set of distance distributions, which enable the exact characterization of coverage probability and throughput. For numerical evaluation, we specialized the setup to the case where users and SBSs are clustered with two independent normal distributions. Our analysis demonstrates that as the number of SBSs reusing the same resource block increases (higher frequency reuse), coverage probability decreases whereas throughput increases. Thus the same resource block can be aggressively reused by more SBSs as long as the coverage probability remains acceptable.