低密度奇偶校验码迭代译码算法的误码平台特性

Error floor properties of low-density parity-check codes using iterative decoding algorithms

为研究低密度奇偶校验(LDPC)码在采用不同译码算法时的误码平台特性,利用硬件仿真系统实际测试数据,对LDPC码采用不同迭代译码算法的误码平台特性进行统计分析。分析结果表明:LDPC码采用和积(SP)算法或修正最小和(MMS)算法译码失败后,残留错误比特数目一般很小;因此,LDPC码可作为级联码的内码,实现极低的误比特率。与MMS算法相比,SP算法译码后错误码字中的残留错误比特通常更少,更适合级联码。基于上述分析设计的级联码可以在较低的门限下实现低于10-10的误码率。

Error floor properties of low-density parity-check （LDPC） codes using different decoding algorithms were statistically analyzed utilizing test data from a hardware evaluation platform. The analysis shows that the number of residual error bits in an error codeword after decoding failure using the sum-product （SP） algorithm or the modified rain-sum （MMS） algorithm is usually quite small; therefore, LDPC codes can serve as the inner code in a concatenated coding system to achieve an ultra low bit error rate. The analysis also shows that SP algorithm is more suitable for a concatenated coding system than MMS algorithm since less residual error bits occur when using the SP algorithm, Concatenated codes based on the analysis achieve hit error rates lower than 10^-l0 with a low decoding threshold.