基于部分码字译码的MPA检测算法  

MPA detection algorithm based on partial code-words decoding

作　　者：张旭宁 葛文萍[1] 刘希腾 ZHANG Xuning;GE Wenping;LIU Xiteng(College of Information Science and Engineering,Xinjiang University,Urumqi 830046,China)

机构地区：[1]新疆大学信息科学与工程学院

出　　处：《现代电子技术》2019年第21期18-22,共5页Modern Electronics Technique

基　　金：新疆维吾尔自治区研究生科研创新项目(XJGRI2017019)~~

摘　　要：稀疏码多址接入技术(SCMA)是一种新型非正交多址接入技术。针对SCMA中消息传递算法进行多用户检测复杂度较高的问题,提出基于部分码字球形译码多用户检测算法(PCSD-MPA)。该算法通过设置球型半径减少参与迭代的用户码字,并根据SCMA的非正交特性引入信道质量这一新的判决机制,从而进一步降低MPA算法的计算复杂度。同时采用部分码字初始概率均等分配策略,有效提升了算法的收敛速率。仿真结果表明,在球形半径设定合理的条件下,PCSD-MPA在几乎不改变系统误比特率性能的情况下降低了MPA的复杂度,且该算法的计算复杂度随着SNR的增大明显降低。Sparse code multiple access(SCMA)technology is a new non-orthogonal multiple access technology.Since the message passing algorithm in SCMA has high complexity in multiuser detection,a partial code-word spherical decoding based multiuser detection algorithm(PCSD-MPA)is proposed in this paper,which reduces the number of user codes participating in the iteration by setting the spherical radius,and introduces a new decision mechanism,channel quality according to the nonorthogonal characteristics of SCMA to further reduce the computational complexity of MPA algorithm.A partial code-words initial probability equal allocation strategy is adopted to effectively improve the convergence rate of the algorithm.Simulation results show that the proposed PCSD-MPA can reduce the complexity of MPA almost without changing the bit error ratio under the condition of reasonable set-up of sphere radius.The computational complexity is obviously reduced with the increase of SNR.

关 键 词：稀疏码多址接入 非正交多址接入 消息传递算法 多用户检测 球形译码 信道质量 

分 类 号：TN929.5[电子电信—通信与信息系统] 34[电子电信—信息与通信工程]