Context aware network-assisted hand-off management and interference mitigation scheme for heterogeneous networks

Femtocells are small, low-power, low-cost randomly deployed base stations, which are deployed by end users without proper cell planning or resource optimization. This ad-hoc deployment results in many technical issues that demand an effective solution to exploit the co-channel deployment with macro-cells. One typical problem is cross-tier interference especially at the cell edge where macro user equipments behave as `loud neighbors' and interfere with neighboring femto base stations. In this paper, we attempt a geographically-distributed hybrid access scheme by incorporating the nature of involved interferences. We divide the whole coverage area of a macrocell into two areas, namely inner and outer femtocells. We then propose a virtual-coverage-driven femtocell algorithm to mitigate inter-femtocell interferences along with a context-aware network-assisted handover management scheme to facilitate smooth handoffs among from the macrocell to femtocells. Finally, extensive simulation results are provided to verify the enhancement of proposed scheme for the network-wide user equipment throughput.