Abstract: Abstract: Turbo code’s iterative decoding can provide an excellent performance, but it also brings on decoding complexity, decoding delay and power consumption. This paper analyzes iterative decoding and its algorithm for turbo codes, proposes an approach of optimizing turbo code’s iterative decoding, CRC is used into turbo decoding iterative processes to control the number of iterations. The simulation result shows the proposed scheme can reduce decoding delay and average number of iterations with negligible decoding complexity and performance degradation, especially in large SNR.

Key words: Turbo codes, cyclic redundancy check, iterative decoding

摘要： 摘 要 迭代译码可以提高Turbo码的译码性能,但也是增加译码复杂性、延时及功率损耗的主要原因。本文在分析Turbo码的迭代译码原理和译码算法的基础上,提出一种迭代译码的优化设计方法(Turbo-CRC),即利用循环冗余检测码CRC对Turbo译码器硬判决的输出结果进行检测,可以有效地减小平均迭代次数。计算机仿真结果表明在不降低译码性能和不增加系统复杂度的情况下,使用该方法可以有效地减小平均迭代次数和译码延时,尤其是在大信噪比时,效果更好。

关键词: Turbo码 循环冗余检测CRC 迭代译码