Non-orthogonal Multiple Access Based On User Grouping And Multiple Layer Modulation For 5G

Multiple access technology as the basis for the evolution of wireless communica-tions technology,providing resources for each user in the wireless communication sys-tem,so that all users can simultaneously transmit wireless environment.Each genera-tion replacement for wireless communication revolution is accompanied by multiple access technology.With the continuous expansion of the size of the next generation network,the fifth generation of mobile communication system to enhance the capacity of the increasingly high demand.The foreseeable future of mobile Internet services will show explosive growth.However,the traditional orthogonal multiple access scheme already facing performance bottlenecks,it is difficult to meet the needs of the next generation of mobile communications.Therefore,the study of multiple access technologies for 5G has a very important significance.Now,in the academic community it has been proposed non-orthogonal multiple access technology program,which is more representative of the region based on the power of non-orthogonal multiple access techniques.Non-orthogonal multiple access techniques NOMA's power division multiple access system utilizes power-sized dis-tinguish different users.Frequency-domain transmit information to all users in the same time,can greatly improve system capacity.However,the problem with conven-tional power domain non-orthogonal multiple access technique that faced with the in-crease in the number of users,the end user decode delay will increase,and finally a power allocation fewer users of the system capacity is too small,It lost the meaning of transmission.Through the introduction of the constellation points rotation superim-posed modulation technology to improve the traditional power domain non-orthogonal multiple access techniques,the number of users can be 2-3 times more technically car-ried in conventional power domain non-orthogonal multiple access.Specific research contents and results are as follows:First,this paper introduces the implementation of traditional non-orthogonal mul-tiple power domains and power domains proved non-orthogonal multiple access scheme from the perspective of information theory to meet the optimal channel capac-ity.In addition,we have the traditional non-orthogonal multiple access technology so-lutions combined with OFDM modulation scheme.The design of the sender,the re-ceiver design,power distribution technology for the scene and other issues were dis-cussed.Secondly,this paper describes the constellation points rotation superimposed pro-gram,aspects from the constellation points rotation superimposed implementation,performance analysis,and power distribution,etc.,proves that the program can meet in the uplink channel capacity theoretically,but also has flexible high,easy to combine the advantages of other technologies.Finally,we have the traditional power domain non-orthogonal multiple access technology solutions and constellation rotation superimposed modulation scheme pro-posed by combining the new power domain non-orthogonal multiple access techniques.This article focuses on the overall system design new power domain non-orthogonal multiple access technology,the transmission end design,the receiver design,power distribution under different needs,as well as the optimal angle distribution scheme.Through simulation,we can out of the following conclusions:In the uplink,the new power domain non-orthogonal multiple access scheme proposed under the same cir-cumstances the number of users than traditional power domain non-orthogonal multi-ple access scheme in performance It has significantly improved.In addition,the pro-posed power allocation algorithm can be well done performance and fairness of regu-lating the whole system.Review article starting from the traditional power domain non-orthogonal multi-ple access technology,focusing on the new power-domain non-orthogonal multiple access scheme improved.The new non-orthogonal multiple access scheme compared to conventional power domain non-orthogonal multiple access scheme may frequency resources exponentially increase the number of users,with strong theoretical value at the same time.