Research On User Connection Density And Scheduling Algorithm In MMTC Scenario Of 5G System

With the in-depth study of the large-scale machine communication scenario under 5G,it is found that it plays an important role in the scenario of interconnection of all things,but it also brings great challenges.First,there are large-scale terminal devices in the mMTC scenario,which will lead to a sharp rise in the amount of data.Secondly,the terminal equipment under it has high requirements for endurance capacity,and the terminal equipment does not have the characteristics of charging at any time.Therefore,reasonable resource allocation is very important.This thesis mainly studies the performance of different resource scheduling algorithms according to the main scene characteristic parameter connection density in the 5G system mMTC scenario.The main work of this thesis will be briefly introduced below:Firstly,this thesis studies three basic resource scheduling algorithms:round robin algorithm,proportional fair algorithm and max carrier to interference resource algorithm.By consulting the relevant literature,it is found that some scholars have combined the two scheduling algorithms,for example,combining the round robin algorithm with the approximate maximum throughput algorithm,and proposed a new scheduling method using a fixed threshold to divide the scheduling resource blocks.However,the above methods still have shortcomings.In order to further balance the fairness of resource allocation and the connection density of terminal equipment in a certain area,based on the combination of round robin and approximate maximum throughput algorithm proposed by scholars,this thesis makes the first improvement,that is,the proportional fairness algorithm is used to replace the round robin algorithm and the max carrier to interference algorithm is used to replace the approximate maximum throughput algorithm,Because the total throughput of the proportional fair algorithm system is relatively high and can ensure relatively high connection density,the max carrier to interference algorithm can reduce the complexity of the algorithm and improve the computational efficiency.According to the simulation results,the simulation results of the first improved algorithm are closer to the max carrier to interference algorithm,but it is not enough to improve the fairness.In order to further improve the fairness of system resource allocation,the second improvement is made,that is,the dynamic threshold equalization method is used to evenly allocate the resource blocks to two basic algorithms to improve the fairness of the whole system.Secondly,in order to verify the performance of the algorithm,this thesis develops a 5G system level simulation platform.This thesis introduces the construction process of the platform and describes the specific implementation of the above scheduling algorithm.In addition,in order to verify the correctness of the platform,the platform is verified.Finally,this thesis makes a comprehensive study on the above scheduling algorithms from the aspects of connection density,system throughput,fairness of terminal equipment and so on.According to the evaluation results of the basic scheduling algorithm,the accuracy of the simulation platform can be further verified.According to the evaluation results of the extended algorithm,the second improved algorithm has the best fairness,the first improved algorithm has better performance in throughput,signal-to-interference noise ratio and connection density,and the priority equalization method has medium performance among the three algorithms,Compared with the basic proportional fairness algorithm and max carrier to interference algorithm,the three algorithms have a better balance between the connection density of terminal equipment and the fairness of overall system resource allocation in a certain area.