Browsing by Author "Xiaobin, Yang"

Now showing 1 - 1 of 1
  • Thumbnail Image
    ItemOpen Access
    Interference Management in Heterogeneous Cellular Networks
    (2016) Xiaobin, Yang; Fapojuwo, Abraham; Messier, Geoffrey; Sesay, Abu-Bakarr; Petovello, Mark; Witold, Krzymien
    Heterogeneous cellular networks (HetNets), comprising one or more tiers of small base stations (BSs) overlaid on the tier of well-planned macro BSs, have been commonly recognized as a cost-effective solution to cater to explosive demands on mobile data traffic. However, HetNets also bring some unique challenges such as unplanned deployment of small BSs and increased complexity of interference management. Interference in HetNets becomes one of the major obstacles to capacity improvement and coverage enhancement. In this thesis, analytical approaches are developed to investigate interference statistics and the performance of 2-tier HetNets including coverage probability and spectral efficiency in mathematical expression, and some insights are revealed on the relationships of interference statistics and network performance with system parameters such as frequency reuse factor, transmission probability, and the signal-to-interference ratio (SIR) gap from Shannon capacity. Specifically, the interference and performance impact of Rician fading and lognormal shadowing are analytically investigated, first based on the Poisson point process (PPP) model where the locations of BSs in each tier are modeled as a PPP. Second, a hybrid model of HetNets is established which considers both location regularity of macro BSs and topological randomness of small BSs, where the coverage probability and the spectral efficiency are derived under different propagation conditions and the significance of macro BS deployment planning is revealed. Third, based on the aforementioned analyses, a well-known interference management technique of fractional frequency reuse (FFR) applied in the tier of macro BSs is studied in detail, and its optimal parameter settings in terms of spectral efficiency and suitable environments are identified. Finally, a particular interest is attached to multiple antenna technologies including classical beamforming and transmit diversity, which are studied with consideration of the impact of intra-tier and inter-tier interference in HetNets.