Stochastic Analysis of Uplink Interference in Two-Tier Femtocell Networks: Open Versus Closed Access

We introduce a stochastic analytical framework to compare the performance of open-access and closed-access modes in a two-tier femtocell network with regard to the uplink interference and the outage at both the macrocell and femtocell levels. A stochastic geometric approach is employed as the basis for our analysis. We present numerical methods to characterize the distributions of the uplink interference and the outage probabilities. We further derive sufficient conditions for the open-access and closed-access modes to outperform each other in terms of the outage probability at either the macrocell level or the femtocell level. This leads to closed-form expressions to upper and lower bound the difference in the targeted received power between the two access modes. Simulations are conducted to validate the accuracy of the analytical model and the correctness of the bounds.