Energy efficient dynamic network configuration in two-tier LTE/LTE-A cellular networks

With the increasing demand of broadband wireless communication networks, users have an increasing need of the wireless broadband service coverage and the wireless access quality. To alleviate this problem, several novel techniques are proposed. One of these techniques is femtocells. A femtocell can be used to increase the coverage of wireless broadband service indoors or at hotspots and raise both data transmission rate and access quality. Although the use of femtocells can greatly benefit, deploying large number of femtocells consumes tremendous energy. In order to respond to the problem of global climate change, energy saving is an important issue. This paper discusses how to minimize the energy consumption of femtocells and optimize the energy efficiency of networks while still providing both the same data transmission rate and wireless broadband service coverage. In this work, considering path loss, modulation and coding schemes (MCSs), bit-error-rate (BER) and group mobility, we propose a green handover and dynamic femtocell wake up approach. In default, femtocells are stay in idle mode when no user equipment (UE) connecting to it. A femtocell transits to active mode only when detecting UEs and the efficiency of using the femtocell is better than the macrocell. By this way, not only users can benefit from the femtocells but also femtocells can reduce unnecessary power consumption. Simulation results show that our method performs better than the previous methods in power consumption, energy efficiency and throughput in both 3G/4G wireless communication networks.