Active User and Data Detection for Uplink Grant-free NOMA Systems  

作　　者：Donghong Cai Jinming Wen Pingzhi Fan Yanqing Xu Lisu Yu 无 

机构地区：[1]The College of Cyber Security,Jinan University,Guangzhou 510632,China [2]The Institute of Mobile Communications,Southwest Jiaotong University,Chengdu 610031,China [3]The State Key Laboratory of Rail Traffic Control and Safety,Beijing Jiaotong University,Beijing 100044,China [4]The School of Information Engineering,Nanchang University,Nanchang 330031,China

出　　处：《China Communications》2020年第11期12-28,共17页中国通信（英文版）

基　　金：supported by National Natural Science Foundation of China(NSFC)under Grant No.62001190;The work of J.Wen was supported by NSFC(Nos.11871248,61932010,61932011);the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme(2019),Guangdong Major Project of Basic and Applied Basic Research(2019B030302008);the Fundamental Research Funds for the Central Universities(No.21618329);The work of P.Fan was supported by National Key R&D Project(No.2018YFB1801104);NSFC Project(No.6202010600).

摘　　要：This paper proposes some low complexity algorithms for active user detection(AUD),channel estimation(CE)and multi-user detection(MUD)in uplink non-orthogonal multiple access(NOMA)systems,including single-carrier and multi-carrier cases.In particular,we first propose a novel algorithm to estimate the active users and the channels for single-carrier based on complex alternating direction method of multipliers(ADMM),where fast decaying feature of non-zero components in sparse signal is considered.More importantly,the reliable estimated information is used for AUD,and the unreliable information will be further handled based on estimated symbol energy and total accurate or approximate number of active users.Then,the proposed algorithm for AUD in single-carrier model can be extended to multi-carrier case by exploiting the block sparse structure.Besides,we propose a low complexity MUD detection algorithm based on alternating minimization to estimate the active users’data,which avoids the Hessian matrix inverse.The convergence and the complexity of proposed algorithms are analyzed and discussed finally.Simulation results show that the proposed algorithms have better performance in terms of AUD,CE and MUD.Moreover,we can detect active users perfectly for multi-carrier NOMA system.

关 键 词：non-orthogonal multiple access massive connection active user detection channel estimation multi-user detection and alternating direction method of multipliers 

分 类 号：TN929.5[电子电信—通信与信息系统]