Two-Level Resource Allocation Scheme for Macrocell-Femtocell Overlay Networks

Abstract

The macrocell-femtocell overlay LTE-Advanced network is a promising means by which to extend coverage and support higher data rates for mobile multimedia services (MMS). This study proposes a two-level resource allocation to guarantee service continuity of MMS in a macrocell-femtocell overlay LTE-Advanced network. First we consider the hybrid approach in which individual resources are arranged for dedicated use by the macrocell and femtocell and an additional common resource for their shared use. Different fractions of this common resource will be distributed periodically to the macrocell and femtocell in proportion to the occupancies of the dedicated resources in the macrocell and femtocell. Second we apply different subchannel allocation strategies to the macrocell and femtocell based on the behaviors of each cell. For the macrocell, our scheme allocates the subchannel whose channel gain is the maximum for each user. By contrast, for the femtocell, the subchannels that have been occupied most frequently are allocated preferentially to the user to maximize the reusability of the resource. In this way, our proposed scheme increases the resource utilization efficiencies and thereby guarantees service continuity of MMS in a macrocell-femtocell overlay network. We performed a simulation to evaluate our scheme regarding outage probability, handover failure rate, blocking rate, and total packet throughput.