码率自适应原模图LDPC码的设计  

Design of rate-compatible protograph LDPC codes

作　　者：王志娜[1] 肖旻[2] 王琳[3] 

机构地区：[1]重庆邮电大学重庆市移动通信重点实验室,重庆400065 [2]厦门理工学院电子工程系,福建厦门361005 [3]厦门大学通信工程系,福建厦门361005

出　　处：《重庆邮电大学学报（自然科学版）》2012年第1期55-59,共5页Journal of Chongqing University of Posts and Telecommunications(Natural Science Edition)

基　　金：国家自然科学基金(60972053)~~

摘　　要：无线通信信道的时变性,使得纠错编码必须具备码率自适应的功能。原模图低密度奇偶校验码(low density parity check code,LDPC)可通过删余和扩展实现码率自适应,并能解决传统LDPC码编码复杂度高的难题。将具有原模图结构的AR4JA码(accumulate repeat-4 jagged-accumulate code)作为母码,提出"逐节点删余"算法,实现AR4JA码率从0.5～0.8的变化,利用矩阵扩展实现码率从0.5～0.25的降低。在加性高斯白噪声信道(additive white Gaussian noise,AWGN)下的仿真结果表明,在BER为10-6数量级处,结合删余和扩展方法构造的码率自适应AR4JA码并未出现错误地板。Over time-varying wireless channel,it is necessary for error-correction codes to be rate-compatible.Protograph LDPC codes can achieve rate-compatibility through puncturing and extending;and solve the problem that the encoders of tradition LDPC codes are more complex.With the AR4JA code which can be represented by protograph,we construct a rate-compatible family of AR4JA codes with rates ranging from 0.5 to 0.8 using the algorithm of ＂puncturing node by node＂.To obtain the lower rates from 0.5 to 0.25,matrix expansion is also used.Simulation results over AWGN channel show that using both puncturing and extending we can construct rate-compatible family of AR4JA codes which do not suffer from error floor when BER is 10-6.

关 键 词：码率自适应 原模图低密度奇偶校验码(原模图LDPC) AR4JA码 逐节点删余 扩展 

分 类 号：TN911.22[电子电信—通信与信息系统]