Research On Power Allocation Technology In Non Orthogonal Multiple Access Network

Mobile communication is constantly developing and deepening in the information age.The definition of each generation of mobile communication system is carried out through clear capacity index and professional technology.For example,1G uses multi access frequency division(FDMA),which can only provide users with analog voice services in practical applications.2G,especially in the case of access time-to-time multiplexing(TDMA),can provide system users with low voice and low speed digital data services in combination with actual requirements.3G is mainly concerned with the CDMA,the user peak rate in this case in the range of 2Mbps to dozens of Mbps,and can give a certain technical support to the multimedia data service.4G is the core and key of the frequency division multiple access orthogonal(OFDMA)technology.The user peak rate can reach 100 Mbps to 1 Gbps in this environment,and it can provide powerful technical support for a variety of mobile broadband data services in practical application.In the face of the high differential performance requirements of various scenarios,5G attempts to create solutions for various scenarios,and the current trend of wireless technology innovation has also become diversified.Among them,NOMA uses spectrum efficiency to allow multiple users to occupy the same sub channel,which is different from the resource allocation in OFDMA system.By using continuous interference cancellation NOMA system,the Superposi-tion coded signal can correctly decode and demodulate the receiver.Through a series of formula derivation and simulation experiments,the same diversity gain can be obtained in the DH-NOMA system and the F-NOMA system,but the DH-NOMA system can avoid the failure of the interruption probability.It shows that DH-NOMA guarantees the diversity of users' ? diversity and user diversity in CR-NOMA.D-NOMA achieves a more balanced performance in all multiple access scenarios.For F-NOMA,CR-NOMA,D-NOMA,D-NOMA systems,paired users can always get better performance than OMA.The performance of multi-user downlink D-NOMA system is higher than that of OMA system,because D-NOMA can effectively achieve higher spectrum efficiency.With the continuous increase of D-NOMA users and OMA users in the whole link,the basic performance of D-NOMA is far more than that of OMA.Therefore,NOMA has been considered as a promising candidate for the next generation mobile communication system.