Optimizing Hybrid Access Femtocell Clusters in 5G Networks

Femtocells are an efficient way of reducing infrastructure costs while providing better data rates and coverage. High penetration is expected in the upcoming ultra dense 5G networks, increasing the probability of femtocells´ clusters. Strong resulting interference for nearby non-subscribed users will require interference mitigation techniques. In this paper we present a mechanism where multiple femtocells coordinate their transmission to serve multiple non-subscribed users through hybrid access. First, the spectrum allocation of non-subscribed users by femtocells is determined. Then, we introduce a power control algorithm that is based on two factors. The need for compensation for the subscribed users, due to reduced spectrum, and the effect that any change in power transmission will have on neighbouring femtocells. We evaluate the effectiveness of the algorithm through simulations on individual throughput and overall achieved capacity.