LT码的增强型BP译码算法  

Enhanced LT codes BP decoding algorithm

作　　者：杨晓非[1] 季瑞军 黄胜[1] 张春明[1] 

机构地区：[1]重庆邮电大学光通信与网络重点实验室,重庆400065

出　　处：《电视技术》2016年第3期93-97,共5页Video Engineering

基　　金：国家自然科学基金项目(61371096;61171158);重庆市自然科学基金项目(cstc2013jcyjA40052);重庆市教委科学技术研究项目(KJ130515)

摘　　要：传统的LT码采用的BP译码算法,当不存在度1编码分组时会导致BP译码算法失败,不能继续译码。为了提高译码的成功率,分析了剩余编码分组的结构,提出LT码的再次译码算法(Again Belief Propagation decoding algorithm,ABP)。算法主要思想是BP译码失败后,查找满足条件的可译结构,继续译码,直到译码成功或再次失败,如果失败重复上面步骤直到译码成功或可译结构不存在,从理论上分析了可译结构存在的概率。仿真结果显示译码成功率得到提高。BP decoding algorithm used by general LT code, when degree-1 encoding packet can not be found, BP decoding algo- rithm failure, however, the original BP algorithm can＇t keep decoding. In order to improve the success rate of decoding, the structure of the remaining coded packet is analyzed, this thesis presents a again belief propagation decoding algorithm. When BP deco- ding fails, the proposed search algorithm can be used to find ABP translatable structure according to the proposed algorithm, maintaining decoding until the decryption succeeds or fails. If decoding fails , repeat the above steps until the decryption succeeds or translatable structure can＇t be found. Through simulation, the decoding success rate has been greatly improved.

关 键 词：LT码 BP译码 译码效率 增强型译码算法 

分 类 号：TN911.22[电子电信—通信与信息系统]