外部信息自适应更新的SCMA系统译码方案  

Decoding Scheme for SCMA Systems Based on Adaptive Updating of External Information

作　　者：邓晋 梁燕[1] DENG Jin;LIANG Yan(Chongqing Key Laboratory of Mobile Communication Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学移动通信技术重庆市重点实验室

出　　处：《电讯技术》2019年第11期1344-1350,共7页Telecommunication Engineering

基　　金：国家科技重大专项(2016ZX03001010);重庆市教委科学技术研究项目(KJ1704098)

摘　　要：现有上行稀疏码多址接入(Sparse Code Multiple Access,SCMA)通信系统采用的译码算法中,基于串行策略的消息传递算法(Message Passing Algorithm,MPA)因其在每次迭代过程只选择单个消息进行更新,存在着收敛速度较慢等问题。针对以上问题,提出外部信息自适应更新的MPA算法,每次迭代过程中自适应选取多个残差值较大、相互独立的节点,更新其外部信息以达到提高计算效率的目的。仿真结果表明,该算法可有效提升译码性能,在计算复杂度与译码性能之间取得了较好的平衡。In the uplink sparse code multiple access(SCMA)communication system,during the process of each iteration,only a single message is selected for updating,resulting in the slow convergence speed.To solve these problems,a message passing algorithm(MPA)based on adaptive updating of external information is proposed,which adaptively selects independent nodes with larger residual and updates their external information in each iterative process to improve computational efficiency.Simulation results show that the proposed algorithm can effectively improve the decoding performance and achieves better tradeoff between computational complexity and decoding performance.

关 键 词：5G 稀疏码多址接入 消息传递算法 自适应更新 

分 类 号：TN929.5[电子电信—通信与信息系统]