Reseach On Key Energy-saving Technology In LTE Heterogeneous Networks

Heterogeneous networks tend to be the mainstream networking and the focus of both acdemic and industria circles. HetNet is facing problems by introducing low power node(LPN). Research of HetNet concentrates on system capacity and spectrum efficiency. This work will give some schems on the less studied energy problem,which includes high energy efficiency Pico coverage optimization in HetNet, high energy efficiency access-control strategy and Pico off-on machanism. Energy saving is realized in dynamic volume network senario while ensuring the system perfomance and handing capacity at the same time.Energy efficiency assessment method for LTE HetNet is given based on the models and energy efficiency of the stations by analyzing the energy consumption of each components. Then a simulation and evaluation platform is eatablished using the method. Validity and reliability are ensured by calibrating large-scale and small-scale fading.Based on simulation and evaluation platform of network,this paper has done the following work:This papaer tries to improve network energy efficiency by studying the optimization of micro cell coverage. First, the opitimization of micro cell logic offset coverage is studied and assessed, energy efficiencyof Pico logic offset coverage is also simulated. Second, micro cell uplink pathloss is opimized and energy efficiencyof increasing Pico logic offset coverage under the principle of uplink pathloss, thus both are assessed. Energy efficiency of increasing pico coverage is simulated in different scenario using offset configuration and uplink pathloss approch, respectively. These two methods are compared and evaluated based on the simulated results.Based on the opimized coverage, access control strategy for micro cell high energy efficiency is studied. The stategy increaced Pico coverage with uoplin pathloss method and user capacity is improved. However, it will bring severe interence problems to margin users and will even paralyze the comunication. To solve the problem, macro-micro cooperation is taken for users in the expanded area, which aims at high energy efficiency while ensuring the handing capacity.The last focus of this research is to adapt to the fluxing volumem, which requires the HetNet operating in busy,normal and idle states. In idle state, micro cells are controled due to the fluxing network load on the condition that efficiency comes first, thus the energy saving is realized in low volume. When in heavy volume, energy efficiency is ensured by choosing the OCAC strategy or the RSRP coverage method, which is conducted by judging whether the micro cell is full-loaded.