Ghost Femtocells: an Energy-Efficient Radio Resource Management Scheme for Two-Tier Cellular Networks

The femtocell deployment in 3GPP/LTE sets new challenges to energy efficiency and Radio Resource Management (RRM). Traditional schemes are mainly designed for classical cellular networks while the ad hoc nature of femtocells notably limits the complexity of possible algorithms. Thus, efficient RRM schemes are essential for limiting the interference impact on end-user performance. The goal of this paper is to achieve effective spectral reuse between neighbour cells and reduce the femtocell downlink power consumption while guaranteeing the QoS of users served by both macro and femto base stations. We discuss the effectiveness of two resource management schemes that limit the overall interference per Resource Block (RB) generated outside the coverage range of a femtocell while reducing the transmission power in each RB. Our simulation results show that the proposed RRM schemes enhance the energy efficiency of the overall cellular network while improving both macrocell and femtocell throughput.