Modeling and Analysis of OFDMA-NOMA-RA Protocol Considering Imperfect SIC in Multi-User Uplink WLANs  

作　　者：Hailing Yang Suoping Li Duo Peng 

机构地区：[1]School of Science,Lanzhou University of Technology,Lanzhou,730050,China [2]School of Computer&Communication,Lanzhou University of Technology,Lanzhou,730050,China

出　　处：《Computers, Materials & Continua》2024年第6期5273-5294,共22页计算机、材料和连续体（英文）

基　　金：funded in part by the National Natural Science Foundation of China under Grant 61663024;in part by the Hongliu First Class Discipline Development Project of Lanzhou University of Technology(25-225305).

摘　　要：To address the problems of network congestion and spectrum resources shortage in multi-user large-scale scenarios,this paper proposes a twice random access OFDMA-NOMA-RA protocol combining the advantages of orthogonal frequency division multiple access(OFDMA)and non-orthogonal multiple access(NOMA).The idea of this protocol is that OFMDA is used to divide the entire frequency field into multiple orthogonal resource units(RUs),and NOMA is used on each RU to enable more users to access the channel and improve spectrum efficiency.Based on the protocol designed in this paper,in the case of imperfect successive interference cancellation(SIC),the probability of successful competition subchannels and the outage probability are derived for two scenarios:Users occupy the subchannel individually and users share the subchannel.Moreover,when two users share the channel,the decoding order of the users and the corresponding probabilities are considered.Then,the system throughput is obtained.To achieve better outage performance in the system,the optimal power allocation algorithm is proposed in this paper,which enables the optimal power allocation strategy to be obtained.Numerical results show that the larger the imperfect SIC coefficient,the worse the outage performance of weak users.Compared with pure OFDMA and NOMA,OFDMA-NOMA-RA always maintains an advantage when the imperfect SIC coefficient is less than a specific value.

关 键 词：Orthogonal frequency division multiple access(OFDMA) non-orthogonal multiple access(NOMA) random access(RA) imperfect successive interference cancellation(Imperfect SIC) outage probability 

分 类 号：TN92[电子电信—通信与信息系统]