Research On Power Allocation Of Non-orthogonal Multiple Access

With the rapid development of the economy and the increasing living standards of the people,the demand for mobile services is increasing.New services and a large number of diverse device communication requirements pose a huge challenge to next-generation mobile communication technologies.Due to the scarcity of spectrum resources in communication,it is necessary to study new multiple access technologies.Among them,non-orthogonal multiple access technology has higher spectral efficiency and higher speed,and has become the alternative multiple access technology in the new generation of mobile communication.The main idea is to allocate the same time-frequency resource to multiple users for sharing and overlapping the user signals in the power domain.Therefore,the power allocation problem in non-orthogonal multiple access technology has become a research hot spot,and it is also the focus of this paper.In order to solve the power allocation problem in non-orthogonal multiple access,this paper divides it into two problems,namely user clustering problem and power allocation problem.Firstly,in order to improve the total throughput of the system,a user clustering algorithm based on the matching theory is proposed.Base on the concept of matching theory,preference set is set for each user to be matched and the sub-band to be allocated,matching them one by one to increase overall system performance,resulting in stable user and subband pairing.Then based on game theory,a power allocation algorithm is proposed,which establishes a game model for users in the same frequency band to ensure the communication quality of users,and reduces the power consumption of user equipment as much as possible so that the user achieves a balance between power and signal to noise ratio during the game.The simulation results show that the proposed user clustering algorithm has faster convergence speed,and the performance is slightly less than the exhaustive method but the complexity is lower.The proposed power allocation algorithm effectively reduces the power consumption of the user equipment in the system and guarantees the user's Communication service quality.