速率无损失的空间耦合LDPC码  

Rate-Loss-Free Spatially Coupled LDPC Codes

作　　者：张亚坤 周林[1,2] 陈辰 贺玉成[1,2] ZHANG Ya-kun;ZHOU Lin;CHEN Chen;HE Yu-cheng(The Xiamen Key Laboratory of Mobile Multimedia Communications,National Huaqiao University,Xiamen,Fujian 361021,China;The State Key Laboratory of Integrated Services Networks,Xidian University,Xi’an,Shaanxi 710071,China)

机构地区：[1]华侨大学厦门市移动多媒体通信重点实验室,福建厦门361021 [2]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071

出　　处：《电子学报》2019年第12期2590-2595,共6页Acta Electronica Sinica

基　　金：国家自然科学基金(No.61302095,No.61901182);福建省自然科学基金(No.2018J01096);泉州市科技计划之高层次人才项目(No.2018C108R);华侨大学研究生科研创新基金资助项目(No.17013082035)

摘　　要：空间耦合(spatially coupled)LDPC码为通信系统提供了一种全新的接近容量限的方式,但在耦合过程中需要额外添加校验节点,因此存在一定的码率损失.为了消除码率损失,提出了一种新型的耦合方式,首位置变量节点的边展开方式不变,中间位置的边连接到前一个位置的校验节点并依次向后展开,末位置的边与首位置的边成对称分布,从而得到了一种无需添加额外校验节点,码率无损失的SC-LDPC码变体结构.在AWGN信道中通过外部信息转移(extrinsic information transfer)理论分析及误比特率性能仿真,结果表明:相对于SC-LDPC码的传统结构,本文提出的SC-LDPC码变体结构在链长较短时不仅能避免码率损失,并且具有更优的阈值和译码性能,在未来通信系统中更具优势.Spatial coupled LDPC(SC-LDPC) code provides an entirely new way of approaching capacity for communication systems,however,a rate loss caused by additional check nodes during the coupling process.In order to eliminate rate loss,a coupling method was proposed.The edges expansion of the variable node in the first position were unchanged,and the edges of the middle position were connected backwards from the previous position check node,then the edges of the last position were symmetrically distributed with the edges in the first position.Therefore,a rate-loss-free SC-LDPC code was designed without added addition check nodes.Extrinsic information transfer(EXIT) theoretical analysis and bit error rate performance simulation were adopted in the AWGN channel.It is showed the SC-LDPC variant structure is superior to the traditional structure with a shorter coupling chain length,not only can the rate loss be avoided,but also better threshold and decoding performance,it has more advantages in future communication systems.

关 键 词：空间耦合LDPC码 消除码率损失 AWGN信道 外部信息转移 BP译码 

分 类 号：TP302[自动化与计算机技术—计算机系统结构]