Access strategy and dynamic downlink resource allocation for femtocell networks

Femtocells are small, low power cellular base stations (BS) with high potential for coverage extension and offloading voice and wireless data. In this paper, we study the problem of joint access control and spectrum resource allocation in a two-tier femtocell network with one macro base station (MBS) and multiple Femto Access Points (FAP). The objective is to maximize the overall network capacity, while guaranteeing the quality of service (QoS) requirement of all User Equipments (UE). We develop an access scheme for Macro User Equipments (MUE) and a spectrum allocation mechanism for the FAPs. Spectrum allocation is employed as an incentive mechanism to encourage FAPs to serve more MUEs. We also derive an upper bound of the network-wide capacity through a reformulation of the problem. The proposed algorithms are validated and the upper bound is shown to be quite accurate in the simulation study.