Research On MME Load Balancing In LTE System

With the increase of mobile network users,the popularity of intelligent terminals and the mainstream of mobile application services,mobile communications has been showing an explosive growth trend.Mobile Internet services and new services such as M2 M provide users with services,but also pose a major burden on signaling control of the core network,which is likely to cause signaling congestion leading to a decline in the overall performance of the network.The load balancing function of the MME can realize the resource sharing between several MME and share the signaling load,so as to effectively prevent the congestion of the network.This thesis relies on the national science and technology major projects "research on the overall scheme and test evaluation of broadband mobile communication network based on TD-LTE ".Based on the analysis of the basic technology of MME,this thesis studies the load balancing algorithm of MME,on the other hand,it implements the function of MME load balancing in the experimental system.Firstly,this thesis studies and designs the load balancing algorithm of MMEs.Through the analysis of the factors affecting the perfor mance of MME,this thesis select the number of UE attachment and the number of active bearers as the main factor to measure the performance of MME.And the mathematical model is used to design the multi-criteria expression of MME weight calculation.On this basis,this thesis makes an improvement on the method of using the fixed cycle to update the weight of the general load balancing strategy.And a new load balancing algorithm is designed,which can adjust the next update time according to the changing trend of the number of users in MME.The new algorithm reduces the number of users to change the trend of perceived granularity,thereby further improving the load balancing ability of MME.The new algorithm enhances the perception of changes in the number o f users,and improves the load balancing ability of MME.Based on the above research,the improved load balancing algorithm is simulated in this thesis.The simulation results show that the improved algorithm improves the performance of MME load balancing,and makes full use of MME resources.In this thesis,based on the design of the MME load balancing algorithm and combined with project requirements,the load balancing function is realized in the MME software.Based on the realization of MME technology in the national science and technology major projects,the MME software in the OpenAirInterface-4G which is a open source project is improved.The load balancing function of MME is realized by adding the statistical function,MME weight calculation function,the definition of related message and the interactive process of MME configuration update.Finally,the MME software is tested by builting a simple MME pool.In this thesis,the basic process of MME and the MME load balancing process are tested respectively,and the effectiveness of the MME software is verified.