Femtocell Networks

Abstract

The increasing demand for mobile communication requires an ever denser network coverage. One of the promising solutions is to communicate via femtocells. In a femtocell user equipment connect to the consumers’ broadband internet connection via an access point that is similar to aWi-Fi router. Interference is one of the central problems in wireless communication networks. In the macrocell setting with a few, fixed antennas frequency allocation and reuse is manageable. In the femtocell setting, however, we deal with a large number access points that are distributed in an ad-hoc fashion and frequency allocation strategies must be adaptable to the environment. We look at the cooperative approach where coalitions of femtocell access points coordinate their frequency scheduling to avoid within-coalition interferences. The models we consider are based on two different communication techniques: frequency division and interference alignment. Forming the grand coalition would be the best from the point of view of coordination, but the cost of communication among coalition members must not be ignored. Currently these models have a cap on the total communication cost among femtocell access points to limit the size of coalitions. The optimal coalition structures are determined using the recursive core, and it helps to achieve a 380% service improvement over the noncooperative case.