Design And Implementation Of Interference Coordination Algorithm In 5G Ultra Dense Network

Ultra-dense network is a new type of networking method created by the fifth-generation mobile communication system(fifth-generation,5G)in order to meet higher traffic requirements and more terminal access.Ultra-dense network is to obtain a large number of spectrum reuse and to achieve a hundred times increase of the whole system capacity in hot areas such as crowded traffic or public gatherings through the densification of small base station deployment.But the enhancement of interference is inevitable.Due to the further reduction of the distance between small base stations,the increase of interference sources for a single base station or a single user,as well as the randomness of the distribution of small stations and the uncertainty of the deployment of small stations make the interference in Ultra dense network quite different from that in traditional communication system.Therefore,the interference coordination in ultra-dense networks becomes particularly important.This thesis focuses on the interference coordination between base stations in ultra-dense networks.Firstly,a semi-cluster interference coordination of small cells centered on user equipment based interference coordination algorithm is proposed for micro-micro scenes in ultra-dense networks.This algorithm considers the interference status of users under the base station,and uses it as a basis to classify each base station.Then,on the basis of classification,The base stations with strong mutual interference are set into a cluster.According to the different Qo S(Quality of Service)levels of the services,the coloring graph method is used to meet the needs of high priority users as much as possible on the basis of ensuring the lowest requirements of low priority users.The simulation results show that compared with the enhanced interference coordination algorithm in LTE,this algorithm focus on the different needs of different users based on the increase of system speed,and improves the overall system user satisfaction.Secondly,this thesis studies interference coordination in macro-micro scenarios in the network,and proposes a multi-user access interference coordination algorithm based on coalition game.The algorithm addresses the problem of strong interference caused by random access by a large number of users,and clusters small base stations according to the user access,and unites the macro base stations,regarding each base station as an alliance,and regarding the user's choice of base station access as a game process.By selecting the best base station access for each user,it can reduce the impact of interference and improve the SNR.The algorithm reasonably allocates system resources to reduce system interference and improve system performance.The simulation results show that as the number of iterations of the algorithm increases,the interference in the system decreases and the total energy efficiency increased.With the increase of the number of small base stations,the system needs more games to achieve stable state.Finally,based on the research done in this thesis,an interference coodination protocol is designed,which is applied in the ultra-dense network scene.The SDN(software defined Networking)controller is used to complete the interference coordination in the system.The protocol consists of three parts: control module,parameter mobile module and interference coordination module.In the ultra-dense network scenario built in the laboratory,the interference configuration modification of the base station and the redirection function of the user in the protocol are tested.The experimental results show that the interference coordination protocol can effectively reduce the interference in the system and improve the capacity.