Research On Wireless Resource Management Scheme In Ultra-dense Network

With the advent of The Fifth Generation(5G)mobile communication technology,Ultra-Dense Networks(UDN)has gradually come into people’s vision.Through more intensive wireless network infrastructure deployment,UDN effectively alleviates the situation of spectrum efficiency and capacity improvement in 5G network construction.However,compared with the traditional cellular network,the wireless environment in UDN is complex and the interference in UDN is changeable.How to effectively carry out collaborative management and resource allocation has become a key problem to be solved.In this thesis,we mainly study the related issues of resource management in ultra-dense networks including resource allocation in two user association modes.Firstly,we explore the spectral radius condition that the Signal to Interference plus Noise Ratio(SINR)of all users in the system is not less than the specified threshold when the user and the access point are connected one to one in a single channel.And the influence of different factors on the system spectral radius is explored through simulation.Secondly,under the condition of multi-channel,in order to improve the probability of normal communication between users in the channel,we propose a one-to-one association scheme between users and access points according to the conclusions drawn from the spectral radius correlation simulation.This scheme allows users to select the closest access point to connect.In other words,the strongest access point was selected to serve users through Average Received Link Power(ARLP).And on the basis of this correlation scheme,a heuristic sub-channel allocation algorithm based on clustering is proposed by using the analysis method based on spectral radius.At the same time,in order to reduce energy consumption and achieve the goal of minimizing the overall value of the transmission power of the access points,a distributed power allocation algorithm based on Kalman filter was proposed.The simulation results indicate that the power allocation algorithm can capture the dynamics of the time-varying channel,and then can realize the allocation of the transmission power of the access point.Finally,for the case where the spectral radius condition is not satisfied in the sub-channel,we propose a user-centric access point cooperation scheme based on the Coordinated Multi-Point(CoMP)transmission technology.This scheme utilizes ARLP to adjust the number of candidate access points to serve users.Considering the user’s demand for data transmission rate in reality,we propose a multiple sub-channel allocation algorithm,and the algorithm is simulated and analyzed.The influence of the number of different cooperative access points on the network is analyzed by simulation,and it is verified that the sub-channel allocation algorithm can effectively improve the sum rate.