基于循环差族构造的高码率低密度校验码短码  

Construction of short block length,high rate low-density parity-check codes based on cyclic difference families

作　　者：丁溯泉[1] 杨知行 王军[1] 潘长勇[1] 

机构地区：[1]清华大学电子工程系微波与数字通信技术国家重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2007年第7期1144-1146,共3页Journal of Tsinghua University(Science and Technology)

摘　　要：为了降低编码的复杂度,基于组合数学的方法构造出一类高码率低密度校验(LDPC)码短码。该方法由循环差族构造出一类参数λ为1的平衡非完全块设计(BIBD),再基于这些BIBD构造LDPC码。构造出的LDPC码具有准循环特性,因此编码复杂度低。码字的Tanner图中没有长度为4的环路,在采用置信度传播译码时具有很好的译码性能。仿真结果表明:基于循环差族构造出的LDPC码具有与随机构造的LDPC码相当的性能。构造出的码字适用于手持数字视频广播系统。To reduce encoding complexities, a class of short block length, high rate low-density parity-check （LDPC） codes, is constructed based on cyclic difference families. A class of balanced incomplete block designs （BIBD） with λ = 1 is first constructed based on the cyclic difference families. Then the LDPC codes are constructed based on the BIBD. These codes are quasi-cyclic codes so they can be efficiently encoded. Furthermore, the Tanner graph of the codes is free of cycles of length 4 so the codes perform well with belief propogation decoding. Simulation results show that the codes constructed based on the cyclic difference families perform equally well as randomly generated LDPC codes. The codes can be applied to digital video broadcasting systems for handheld terminals.

关 键 词：信道编码 低密度校验码 循环差族 平衡非完全块设计 准循环码 

分 类 号：TN911.22[电子电信—通信与信息系统]