Improving UE SINR and networks energy efficiency based on femtocell self-optimization capability

Femtocells, which provide an improved SINR for user equipment (UE) inside homes and offices, have been widely deployed jointly with macrocells in heterogeneous networks (Het-Net). With self-configuration and self-optimization functionalities of self-organization networks (SONs), femtocells can minimize the impact on macro cellular network by adapting transmit power according to surrounding environment. In this paper, we propose a novel self-optimization mechanism for femtocell, which can improve indoor coverage and promote energy efficiency of networks. It allows a femtocell to compare its distance from UE with a threshold (virtual cell size) periodically and turn on or off radio transmission accordingly. Simulation results show that the proposed mechanism achieves a higher indoor signal-to-interference-noise ratio (SINR) and capacity without adding interference to macro network, and gains an average reduction of approximately 58.5% in femtocell´s transmit power consumption.