Interference Management Based On Multi-dimensional Resource Allocation In Heterogeneous Networks

With the popularity of intelligent terminal equipment,the demand of users for data traffic is increasing rapidly.In order to improve the system throughput and spectrum utilization,operators constructs a two-layer heterogeneous wireless network,that is,deploying a number of small stations in the hot areas in the coverage of macro stations.However,the introduction of small stations also brings serious cross-layer interference,and the asymmetry of uplink and downlink results in macro users can only obtain part of the channel state information,which is not conducive to interference coordination.In addition,in the enterprise office area,residential areas and other user-intensive scenarios,there are also problems of shortage of spectrum resources and strong correlation of partial user channels,the difficulty of interference management is further increased.Therefore,it is worth studying to implement interference management in heterogeneous wireless network uplink user-intensive scenarios using partial channel state information.Aiming at the problems caused by local user intensive and the advantages and disadvantages of interference management algorithms in different dimensions,an interference management algorithm based on multi-dimensional resource allocation is proposed in this paper.The base stations coordinate with each other to jointly optimize the allocation of airspace resources,frequency domain resources and associated base stations,and implement cross-layer interference coordination from multiple dimensions.Firstly,this paper model the interference management problem by maximizing the sum of user rate and taking it as the objective function,and use suboptimal solution to solve the target problem from the two aspects of space-frequency joint resource allocation and associated control.Secondly,under a fixed decision threshold,the base stations coordinate to carry out orthogonal grouping and resource allocation on the users in heterogeneous wireless network according to the channel correlation.If the user group includes macro users that cause strong interference to the small station,the RBs that are orthogonal to the small station users are preferentially allocated to avoid cross-layer interference from the frequency domain.When the frequency domain resource orthogonal to the small station is limited,the base stations cooperate to group users and further utilize spatial resources to eliminate cross-layer interference.Then,when the resource allocation does not enable the user to meet the minimum rate requirement,according to the channel orthogonality between the user who does not meet the demand and other base station users and the throughput gain brought to the system by the user accessing the other base station,the base station changes the associated base station of the user who does not meet the demand,adjusts user grouping and resource allocation,and makes full use of the free airspace resources of other base stations to increase the total system throughput.Finally,the simulation results show that the proposed algorithm can effectively reduce cross-layer interference and improve system throughput.