空间耦合LDPC码在AWGN信道下的性能分析  

Performance of Spatially Coupled LDPC Codes in AWGN Channel

作　　者：张娅妹 陈燕[1] 周林[1,2] 贺玉成[1,2] ZHANG Yamei;CHEN Yan;ZHOU Lin;HE Yucheng(Xiamen Key Laboratory of Mobile Multimedia Communications,Huaqiao University,Xiamen 361021,China;State Key Laboratory of Integrated Services Networks,Xidian University,Xi’an 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：《无线电通信技术》2020年第1期77-81,共5页Radio Communications Technology

基　　金：福建省自然科学基金项目(2018J01096);福建省教育厅科研课题(JAT170035);泉州市科技计划之高层次人才项目(2018C108R);华侨大学研究生科研创新基金资助项目(18014082037)~~

摘　　要：空间耦合LDPC(Spatially Coupled LDPC,SC-LDPC)码由于阈值饱和特性,被证明是未来无线通信系统的有力候选码型。SC-LDPC码是一种卷积LDPC码,在二元无记忆对称信道下采用置信传播译码算法时具有逼近香农限的性能。对SC-LDPC码的构造及其经典的置信传播译码算法进行了阐述,并在加性高斯白噪声信道下进行了性能仿真和分析。仿真结果表明,SC-LDPC码的约束长度越长或最大迭代次数越大,其性能就越逼近香农容量限。SC-LDPC码在误码率为10-5、最大迭代次数为100时,码长20000比码长10000大约有0.68 dB的增益;在误码率为10-5、码长为10000时,最大迭代次数100的SC-LDPC码比最大迭代次数10的码大约有0.66 dB的增益。仿真结果有效验证了SCLDPC码在无线通信系统中的良好性能。Spatially coupled LDPC(SC-LDPC)codes are demonstrated to be strong candidates for future optical communications systems due to the threshold saturating property.SC-LDPC code is a kind of convolutional LDPC code.It has the performance of approaching Shannon limit when using belief propagation decoding algorithm in binary memoryless symmetric channel.In this paper,the construction of SC-LDPC code and its classical belief propagation decoding algorithm are described.The performance of SC-LDPC code in additive white Gaussian noise channel is simulated and analyzed.Simulation results show that the longer the code length of SC-LDPC codes or the greater the maximum number of iterations,the closer the performance of SC-LDPC codes is to Shannon capacity limit.When the bit error rate is 10-5 and the maximum number of iterations is 100,the SC-LDPC code with 20000 code length has about 0.68 dB gain over 10000 code length.When the BER is 10-5 and the code length is 10000,the maximum number of iterations of SCLDPC codes with 100 is about 0.66 dB higher than that of the maximum number of iterations is 10.The results validate the good performance of SC-LDPC codes in wireless communication systems.

关 键 词：空间耦合LDPC码 置信传播译码 加性高斯白噪声信道 

分 类 号：TN911.22[电子电信—通信与信息系统]