A dynamic resource management scheme for two-tier LTE femtocell networks

Recently, the femtocell concept has received considerable attention both in academic and industry as a promising solution for the deep indoor coverage problem as well as the increasing data demand of mobile devices. Large scale femtocell deployments are hindered mainly by the cross tier interference problem spawned by their inherent uncoordinated deployment and the shared use of the limited spectrum resource by the macro and femtocell networks. The spectrum sharing scheme used has a high impact on the total network throughput. Balance is needed between shared and dedicated spectrum to achieve high spectral efficiency and reduce the co-channel interference. This paper proposes a new hybrid spectrum management scheme for the downlink of OFDMA based systems (e.g. LTE system). The proposed scheme dynamically changes the dedicated spectrum bands of macro and femtocell networks based on the level of interference experienced by users. The throughput performance of the proposed scheme is investigated using simulation and is shown to be considerably better than that of the widely used static spectrum partitioning.