Research On Resource Allocation Algorithm In LTE System

With the rapid developing of mobile Internet and the increasing demand for information technology,3G network can not meet the needs of business and market development.LTE networks will gradually become the protagonist of the mobile Internet,which construction will be more than 450 expected in the number of global LTE commercial networks by the end of 2015,and the total global LTE subscribers will reach 1 billion.However,radio resource which is inseparable from mobile communications is extremely limited,and the spectrum resources available for mobile communications continued to decline.How to take rational use of limited radio spectrum resources to provide for the growing user quality of service is a very important issue.The main work are summarized as follows.(1)In this paper,for the current mainstream mobile communication network environment,and in order to improve resource utilization and efficient radio spectrum allocation targets,we proposed and studied LTE system resource allocation algorithm.Based on the analysis of the in-depth study of the characteristics of LTE system resource allocation and Orthogonal Frequency Division Multiplexing(OFDM),Multiple-Input Multiple-Output(MIMO),Hybrid Automatic Repeat request(HARQ),Adaptive Modulation and Coding(AMC),Inter-cell Interference Mitigation and other key technologies,we have discussed the methods and scheme of single-cell LTE system resources allocation.In the study of single-cell LTE system resource allocation,this paper introduces the basic principle and evaluation criteria of Round Robin allocation algorithm,Max C/I allocation algorithm and Proportional Fair allocation algorithm.We found that although the PF allocation algorithm can have compromising effect in the throughput and user fairness,there are still some defects that do not consider the Quality of Service requirements.Therefore in this paper we refines the traditional Proportional Fair allocation algorithm and proposed a new Proportional Fair allocation algorithm based on Qo S.The gap between the modified priority link,through comparing the service rate and guarantee bit rate,in the guarantee under the premise of the complexity of the considered Qo S,system performance is enhanced,has given a chance to more users in the allocation of resources,improve the utilization radio of frequency spectrum.(2)Designing the LTE system and setting up the various parameters,we useMatlab-based LTE system level simulation platform open source LTE system resource scheduling algorithm for the simulation developed by the University of Vienna.In the case we design the same parameter settings,we analysis and compare the throughput,fairness and spectrum efficiency of the three algorithms,i.e.,the Round Robin allocation algorithm ? the Max C/I allocation algorithm and the Proportional Fair allocation algorithm.When taking into account the actual situation,as the wireless medium where mutual interference between different regions and between the various systems,the system performance will change over time.Plus,the data will varies with the position of the user's profile,so we use the averaging method for system simulation for many times.After multiple experiments,the simulation data are averaged to obtain an average result of average user throughput,user fairness,average spectrum efficiency and channel bandwidth.(3)We analysis the simulation result and have some conclusions as follows.The maximum throughput is obtained by the simulation of MAX C/I allocation algorithm,followed by the PF allocation algorithm is the smallest throughput RR allocation algorithm.From the point of view of fairness,MAX C/I allocation algorithm perform worst in fairness,PF allocation algorithm perform best in user access fairness,and RR allocation algorithm is in the middle.RR allocation algorithm has the lowest average spectral efficiency,MAX C/I allocation algorithm has the highest average spectral efficiency,and the performance of user PF allocation algorithm is in the middle.Secondly,as the channel bandwidth throughput increases,and change the channel bandwidth for bandwidth spectrum efficiency worth little change on the conclusions.According to the result,the throughput of systems will get larger and larger,with the change of channel bandwidth which has not significant effect to the spectrum efficiency.The developed Proportional Fair allocation algorithm based on Qo S,offers more opportunity for resource allocation to the User Equipment and increase the spectrum efficiency.In practice,we can choose different resource allocation algorithm based on the simulation results according to different requirements.