Fuzzy Logic Based User Scheduling

Mobile communication technology is developing rapidly.The 5th Generation Mobile Networks has higher requirements on transmission data rate,delay,reliability,and traffic density.In wireless communication systems,user scheduling is an important part of wireless resource management,which is of great significance for improving system performance,and is also one of the important means to avoid communication overload.Hybrid beamforming technology has attracted wide attention because of the combination of the advantages of millimeter Wave and massive MIMO.In an actual multi-user hybrid beamforming system,the base station cannot provide service for all users on the same time-frequency resource because there is interference between users and the number of radio frequency chains of the base station is often smaller than the number of users.In order to obtain better system performance,it is necessary to design a reasonable and feasible user scheduling algorithm.In the hybrid beamforming system,the user scheduling problem needs to be considered in two dimensions of “user” and “beam”.The user scheduling process is the process of matching the beam and the user,so it is more complicated than the traditional user scheduling problem.In the network slicing scenario,in order to achieve isolation between slices,reasonable user scheduling is necessary.In this paper,for the complicated user situation in the hybrid beamforming system,where different users have different needs and we can't measure the user's "activity" by the unified standard,a fuzzy logic based user scheduling algorithm and beam selection algorithm are proposed.The user's default priority,delay and packet size are used as fuzzy inputs.According to the characteristics of the users and the system,the corresponding fuzzy operation and defuzzification process are designed to obtain the user's “activity” sorting list,and the user with higher activity is selected as the scheduled user.A utility function is defined as the objective function.The objective function takes into account the system performance and the requirements of users,and we propose a greedy-based beam selection algorithm based on the idea of grouping.This user scheduling and beam selection algorithm has better performance and lower complexity than traditional algorithms.5G communication needs to meet different needs in various application scenarios,and the network slicing technology is derived.The Radio Access Network is an important part of network slicing.The radio resources are reasonably scheduled to achieve isolation between slices.So resource management is very important.In this paper,the fuzzy logic based scheduling algorithm is extended to the network slicing technology to analyze the business requirements in several major application scenarios.Based on the proportional fair algorithm,we take into account the diverse needs of users and assign weights based on the characteristics of the slices and the characteristics of the business,where the weights are fixed values.We further introduce fuzzy logic,which is equivalent to dynamically assigning weights to slices.This process is more intelligent and flexible.Compared with the proportional fair algorithm and fixed weight algorithm,the algorithm has a good improvement on user fairness.