一种适用于Turbo译码的新型迭代停止算法

New Iterative Stopping Algorithm Suited for Turbo Decoding

针对Turbo码迭代译码延时大的问题,本文提出了一种加速译码的新型迭代停止方法,该方法利用了两个分量译码器输出的对数似然比LLR(Logarithm Likelihood Ratio)的统计特性,简称为LCB(LLR Characters Based)算法。同现存的经典停止准则相比,在相同的比特误码率性能下,新方法有效的降低了译码平均迭代次数,加速了Turbo码译码,可应用于流媒体信号传输系统。

To the issue of high delay for iterative decoding of turbo codes, a new iterative stopping algorithm for accelerating decoding is presented. The new algorithm which is named as LCB algorithm utilizes the statistical characters of logarithm likelihood ratios （LLR） from output of the two constituent decoders. Compared to other classical stopping criterions,the new method can reduce average number of iterations and accelerate turbo decoding under the same bit-error-ratio （BER） performance, and it can be applied to flow- media signal transmission systems.