Research On Resource Allocation Technology Of Hetero-Geneous Cellular Networks

There are more than 60%of telephone services and more than 90%of data traffi,c services indoors in cellular networks.However,the attenuation of electromagnetic signals during transmission can cause indoor signal differences or even blind spots.At present,the solution to such problems is to introduce a featocell,so that the load of the macro base station can be effectively reduced,and a higher data transmission rate and network tlhroughput can be obtained.However,when the femto base station and the macro base station share the same spectrum resource,the macro base station and the femto cell base station may generate cross-layer interference and adjacent femto base stations may generate co-layer interference with each other.Therefore,it is importan,t to study reasonable resource allocation methods to reduce cross-layer interference and common layer interference,which improves the overall network throughput and guarantees user performance.This paper first analyzes the research background significance of the subject and the research status at home and abroad,then focuses on the key technologies of the femtocell,heterogeneous network interference scenarios,and the commonly used resource allocation techniques.Finally,the basic principles of the OFDMA system are analized.Based on the analysis of the above content,this paper studies the resource allocation problem of heterogeneous cellular n,etwork downlink,and considers the interference problem of heterogeneous cellular network from the following two aspects.Considering the power allocation,this paper proposes an improved particle swarm optimization algorithm.The improved algorithm defines the fitness function of the power allocation problem of macro base station and femto base station respectively,and introduces the adaptive weight into the particle swarm optimization algorithm.In the speed update formula,the improved particle swarm optimization algorithm is used to solve the power allocation optimization problem respectively,so as to obtain the optimal solution of the power allocation problem under the premise of ensuring the user service quality.The simulation results show that the improved algorithm can reduce the macro user's outage probability and increase its average throughput compared with the fixed power setting.Compared with the basic particle swarm optimization algorithm,the number of iterations is reduced and the convergence precision is improved.In terms of spectrum allocation,this paper proposes a bat algorithm based on nonlinear dynamic inertia weights.Under the premise of considering the two kinds of interference and satisfying the minimum data transmission rate of the user,An optimization problem targeting heterogeneous throughput is established,and then the proposed bat algorithm is used to solve the objective function,and then the target function is solved by the proposed bat algorithm.The simulation results show that the number of channels and the number of users affect the network throughput.Compared with the Hungarian allocation algorithm,the algorithm effectively improves the network throughput.