| 摘要: |
| 针对低密度奇偶校验(LDPC)码在高信噪比区域可能存在错误平层的缺点，提出了一种低错误平层LDPC码的新构造方法。该方法的基本矩阵由渐进边增长(PEG)算法与近似环额外信息度(ACE)算法相结合，目的是提升基本矩阵中环的连通性；然后将基于分割移位(PS)的循环移位系数矩阵对基本矩阵循环扩展，以此构造出校验矩阵。该方法除了能够改善高信噪比区域的错误平层，还具有码长、码率的任意可设性特点。仿真结果表明，PAP-LDPC(3 600,2 700)码在信噪比为4 dB以后并未出现明显的错误平层。 |
| 关键词: LDPC码 错误平层 PEG算法 ACE算法 分割移位 |
| DOI： |
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| 基金项目:国家自然科学基金资助项目(61472464，61671091,61471075)；重庆市基础与前沿研究计划项目(cstc2015jcyjA0554)；重庆市研究生科研创新项目资助(CYS17241) |
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| A novel construction method of LDPC codes with low error floor |
| YUAN Jianguo,ZHENG Demeng,SUN Lele,ZENG Jing |
| (Chongqing Key Laboratory of Photoelectronic Information Sensing and Transmitting Technology，Chongqing University of Posts and Telecommunications,Chongqing 400065,China) |
| Abstract: |
| Aiming at the disadvantage that Low Density Parity Check(LDPC) codes may exist the fault of the error floor in the high signal-to-noise ratio(SNR) region,a new method for constructing the LDPC codes with low error floor is proposed.The basic matrix of the method is composed of the Progressive Edge Growth(PEG) algorithm and the Approximate Cycle Extrinsic message degree(ACE) algorithm so as to improve the connectivity of the cycle in the basic matrix.The basic matrix is cyclically extended based on the PS's cyclic shift coefficient matrix,so the parity check matrix is constructed.The method can not only improve the error floor in the high SNR region,but also flexibly design the code length and code rate.The simulation results show that PAP-LDPC(3 600,2 700) codes have no error floor above the SNR of 4 dB. |
| Key words: LDPC code error floor PEG algorithm ACE algorithm partition and shift |
