Sensitivity of OFDMA-Based Macrocellular LTE Networks to Femtocell Deployment Density and Isolation

In this paper, we investigate the impact of femtocell deployment density and femtocell isolation on the downlinkperformance of Orthogonal Frequency Division Multiple Access (OFDMA)-based macrocellular Long Term Evolution (LTE) networks by system level simulations. Femtocell isolation is defined as the separation between macro- and femto tiers by wall penetration loss. We evaluate the relation between user throughput and femtocell density for highly-isolated and nonisolated deployments. The system model is based on a Poisson Cluster Process and simulations are carried out with the Vienna LTE system level simulator. We provide results for Signal-to- Interference-Plus-Noise Ratio (SINR), throughput, fairness and gain over non-femtocell-enhanced networks. Our investigations indicate a femto-network's high sensitivity to varying wall penetration loss and we observe that in dense deployments, average user throughput conceals the severe performance degradation of macrocell-attached users. The whole simulation environment together with the fully reproducible results of this paper are made available for download on our homepage.