Research On Radio Resource Allocation Algorithms In Millimeter-wave Massive Mimo NOMA Systems

The rapid development of mobile communication technology leads the emergence and prosperity of new data services.Especially with the rise of concepts such as virtual reality,autonomous driving and Internet of Everything(IoE),people put forward higher requirements for the quality of communication services.Future networks are facing multiple pressures,such as system capacity,user experience rate,transmission delay and scarce resources.Millimeter-wave communications worked in the frequency band for 30 GHz-300 GHz greatly enrich the spectrum resources and alleviate the challenges brought by the shortage of spectrum resources in mobile communication systems.The Massive MIMO technology uses large-scale antenna arrays to enable users to obtain high beamforming gains,which makes up for the shortcomings of high path loss of millimeter wave signals.Non-orthogonal multiple access technology(NOMA)introduces a new dimension-power domain to achieve multiple access,multiple users can share the same orthogonal resources.The introduction of NOMA technology in millimeter-wave Massive MIMO systems can further improve system user access and resource utilization.Therefore,the millimeter-wave Massive MIMO NOMA system is an important technical solution for future mobile communication networks.This work is supported by the research project "Research on Key Technologies of 5G New Radio".The shortage of radio resources in mobile communication systems determines the importance of resource allocation for optimizing system performance.How to efficiently use precious radio resources to better meet the needs of users’ various data services is a major consideration in future mobile communication systems.This paper focuses on the radio resource allocation problem in the millimeter-wave Massive MIMO NOMA system,and proposes a joint beam and power allocation algorithm for system energy efficiency optimization and a joint user and beam power allocation algorithm for user ratio fairness,respectively.The main contents of the paper are as follows:1)The paper introduces the basic concepts and technical characteristics of millimeter-wave,massive MIMO and NOMA technologies,as well as the advantages and challenges of millimeter-wave massive MIMO NOMA systems.And the paper combs the research content of wireless resource allocation and the research status of wireless resource allocation in millimeter-wave massive MIMO NOMA systems.That lays the foundation for subsequent research.2)In order to improve the energy efficiency of the millimeter-wave massive MIMO NOMA system,a joint beam and power allocation algorithm for optimizing system energy efficiency is proposed.In the millimeter-wave massive MIMO NOMA system,a jointly optimizing beam and power allocation optimization problem is proposed with the goal of maximizing system energy efficiency and users’QoS(Quality of Service)constraints.To solve the optimization problem,a low-complexity suboptimal algorithm is proposed.Firstly,a low-complexity beam allocation algorithm was proposed based on stable matching.Then,the fractional programming and sequential convex approximation technology were used to solve the non-convex power allocation problem.At last,it alternates iterative beam and power allocation to obtain the solution of the original optimization problem.Simulation results show that the proposed low-complexity algorithm of joint alternating iteration is effective and superior.In addition,the energy efficiency performance of the millimeter-wave massive MIMO NOMA system is better than that of the millimeter-wave large-scale antenna OMA system in large-scale access scenarios.3)In order to improve the user fairness of the millimeter-wave massive MIMO NOMA system,a joint beam and power allocation algorithm for guaranteeing user fairness is proposed.In the dynamic scenario of millimeter-wave massive MIMO NOMA,a dynamic resource allocation optimization problem is proposed with the goal of improving user fairness and the constraint of users’QoS,in order to pursue long-term fairness of users.To solve the optimization problem,a DQN-JBPA algorithm is proposed.Due to the dynamic characteristics and combination complexity of the optimization problem,this paper designs a dynamic resource allocation model and implementation process for the application scenario based on the DQN algorithm,and then solves the optimization problem.Simulation results show that the proposed DQN-JBPA algorithm is effective and superior,and NOMA technology can improve the fairness of users.