Uplink interference analysis for two-tier cellular networks with diverse users under random spatial patterns

Multi-tier architecture improves the spatial reuse of radio spectrum in cellular networks, and user classification allows consideration for diverse user service requirements. But they introduce complicated heterogeneity in the spatial distribution of transmitters, which brings to new challenges in interference analysis. In this work, we present a stochastic geometric model to evaluate the uplink interference in a two-tier network considering multi-type tier-1 users, tier-2 cells and tier-2 users. Each type of tier-1 users and tier-2 base stations are modeled as independent homogeneous Poisson point process, and each type of tier-2 users are modeled as local non-homogeneous Poisson point process centered at tier-2 base stations. By applying a superpositionaggregation-superposition (SAS) approach, we numerically characterize the interference at of both tiers. Finally, simulation results validate our model and illustrate that our model offers substantial improvement in accuracy compared with the best known approximation model.