Energy Performance Analysis And Optimized Of Heterogeneous Networks Based On Femtocell

With the explosion growth of mobile users and the service requirement, huge economic bring benefits to the operators, but also lead to a sharp increase in energy consumption in the field of ICT industry. Carbon emissions is growing rapidly as well as the wireless communications energy efficiency. Therefore, increase capacity of wireless network while reducing the energy consumption of the network will be the trend for the design of future wireless communications.In this thesis, what we discussion is under the premise of the green communication. At first we elaborated interference and energy efficiency in the Macro-Femto heterogeneous networks. As we know deploy femtocell under the cover of macrocells in the wireless network can increased wireless system capacity, and also reduce the power consumption of the system. However, as there are lots of complex interferences in the heterogeneous network, the system energy efficiency will be decreased. But if we take some measures such as power control or sleep schemes at femtocell base station in heterogeneous network are possible to reduce the interference and the power consumption. Then, we discussed the coverage performance of the system and energy efficiency in theoretically. In this thesis we assume femtocells location based on model of random geometric distribution, for channel model, only considering the pathloss and shadow fading, and interference limited scenarios. we conclusion the coverage performance based on stochastic theory for two-tier cellular networks with diffifent frequency allocation strategy(with the same frequency allocation strategy and the orthogonal frequency allocation strategy), and then we further investigate the optimal energy efficiency performance of the heterogeneous network based on a certain coverage probability. Discussed the relationship between Femto BS number, and heterogeneous network coverage radius and energy efficiency.Finally, according to the different forms of user access schemes, proposed two different sleeping scheme in femtocell base station:based on the user’s noise detection for closed access femtocell, and in densely deployed for an open access femtocell, we can closed the femtocell which have fewer the number of users and the neighboring cells can take care of the coverage. Simulation results show that the two sleep mode we put forward, can reducing the power consumption of the base station and increase the energy efficiency of heterogeneous networks,while ensure the quality of service at the same time.