A coalitional game for femtocell clustering in OFDMA macro-femtocell networks

In this paper, we tackle the problem of resource management in macro-femtocell networks. Dense deployment of femtocells imposes several challenges for a cluster-based resource allocation. Some of those challenges are the trade-off between the level of offloaded traffic from macrocell and bandwidth allocated to femto-tier, the fair distribution of resources, and the mitigation of inter-cluster interference. To overcome these limitations, we propose a coalitional game to form clusters of femtocells that can reduce the resource allocation complexity. Stable clusters are formed based on the core model. Our proposal mainly consists of three components. Namely, a femtocell selection for public users, a coalitional game where cooperative femtocells are rewarded, and a Weighted Water Filling algorithm to allocate resources. Our solution is performed under a rewarding model, which is based on an ideal spectral efficiency and on an effective spectral efficiency. We compare the results of our rewarding model with a non-cooperative model, where femtocells work in closed access mode. Simulation results demonstrate that our proposal improves the femto-tier throughput and the satisfaction of femtocells subscribers.