Research On Interference Management Scheme In Ultra Dense Heterogeneous Networks

The rapid development of mobile network and the Internet of Things has led to the continual pursuit of higher transmission rate,higher communication quality and better service experience.The emerging data services have driven the development of the fifth generation of mobile communication system.As a key technology of 5G,ultra-dense network(UDN)has become a hot research focus.The dense deployment of low-power access points improves the utilization of spectrum resources,it becomes the main mean for 5G to improve system capacity.In UDN,low-power access points are densely deployed,they close the distance between base stations and users.However,the network structure becomes more and more complex,and the deployment of base stations becomes more random,bring new problem to interference management scheme.How to effectively manage the interference in UDN is the focus of this paper.At present,many interference management schemes are available,such as interference elimination,interference randomization,interference coordination,etc.In traditional cellular network,these typical schemes can achieve effectively interference management.However,in UDN,spectrum resources are limited,access point deployment tends to be randomized,interference becomes extremely complex.Therefore the current interference management schemes cannot be directly applied to the UDN,which bring new challenges to interference management scheme.This paper suppresses interference from two aspects,they are frequency reuse and power control.In this paper,the main work are as follows:(1)Introduce the key technologies and challenges of ultra-dense networks,and propose must apply more advanced interference management scheme to suppress interference.(2)A soft frequency reuse mechanism based on HII/OI is proposed.Firstly,the interference in UDN is analyzed,and the scene model is established.Secondly,based on the shortcoming of the fixed soft frequency reuse algorithm,the dynamic frequency reuse algorithm is proposed,the cell edge frequency band is further subdivided into master band,priority band and borrowed band,and adopt High Interference Indicates(HII)and Overload Indicates(OI)to complete the scheduling of the edge band.Finally,an optimal edge band division ratio is obtained by simulation.It also shows that the mechanism effectively suppresses inter-cell interference and improves system throughput.(3)A power control mechanism based on non-cooperative game theory is proposed.First,the UDN scenario is introduced.In this scenario,a network interference controller(NIC)is added,it can set different interference prices for the user's interfering base station.Secondly through the relevant knowledge of game theory,taking the overall throughput of thesystem as the optimization goal,the power control process is abstracted into a non-cooperative game process.Finally,the simulation proves that the mechanism achieves good results and suppresses interference between users without affecting the quality of user communication.