Improved construction of LDPC convolutional codes with semi-random parity-check matrices  

作　　者：MU LiWei LIU XingCheng LIANG ChuLong 

机构地区：[1]School of Information Science and Technology,Sun Yat-sen University [2]School of Physics and Telecommunication Engineering,South China Normal University [3]State Key Laboratory of Integrated Services Networks,Xidian University [4]Laboratory of Quantum Engineering and Quantum Materials,School of Physics and Telecommunication Engineering,South China Normal University

出　　处：《Science China(Information Sciences)》2014年第2期33-42,共10页中国科学（信息科学）（英文版）

基　　金：supported by National Natural Science Foundation of China(Grant Nos.60970041,61173018);Xidian ISN National Key Laboratory

摘　　要：In this paper, we investigate the construction of time-varying convolutional low-density parity- check （LDPC） codes derived from block LDPC codes based on improved progressive edge growth （PEG） method. Different from the conventional PEG algorithm, the parity-check matrix is initialized by inserting certain pat- terns. More specifically, the submatrices along the main diagonal are fixed to be the identity matrix that ensures the fast encoding feature of the LDPC convolutional codes. Second, we insert a nonzero pattern into the sec- ondary diagonal submatriees that ensures the encoding memory length of the time-varying LDPC convolutional codes as large as possible. With this semi-random structure, we have analyzed the code performance by eval- uating the number of short cycles as well as the the bound of free distance. Simulation results show that the constructed LDPC eonvolutional codes perform well over additive white Gaussian noise （AWGN） channels.In this paper, we investigate the construction of time-varying convolutional low-density parity- check （LDPC） codes derived from block LDPC codes based on improved progressive edge growth （PEG） method. Different from the conventional PEG algorithm, the parity-check matrix is initialized by inserting certain pat- terns. More specifically, the submatrices along the main diagonal are fixed to be the identity matrix that ensures the fast encoding feature of the LDPC convolutional codes. Second, we insert a nonzero pattern into the sec- ondary diagonal submatriees that ensures the encoding memory length of the time-varying LDPC convolutional codes as large as possible. With this semi-random structure, we have analyzed the code performance by eval- uating the number of short cycles as well as the the bound of free distance. Simulation results show that the constructed LDPC eonvolutional codes perform well over additive white Gaussian noise （AWGN） channels.

关 键 词：low-density parity-check （LDPC） convolutional code block code memory length CYCLE freedistance 

分 类 号：TN911.2[电子电信—通信与信息系统]