摘要： 传统的串行抵消比特翻转（SCF）译码算法仅用对数似然比（LLR）的绝对值去衡量信息比特译码结果的可靠情况，导致误块率（BLER）过高和翻转的尝试次数较多。提出一种串行抵消比特翻转译码算法PLR-SCF，分析SC译码算法发生错误译码的原因，通过仿真观察LLR、极化信道可靠度和信息位所在的位置与SC译码算法发生首个判决错误之间的关系，并利用上述因素设计一个能准确衡量信息位发生译码错误程度的度量公式。仿真结果表明，相对于传统的SCF译码算法，该算法能够有效降低BLER，特别是在高信噪比下获得的最大信噪比增益约为0.12 dB，翻转尝试次数与SCF减少13.6%。

关键词: 极化码, 串行抵消比特翻转译码, 对数似然比, 首个判决错误, 误块率

Abstract: The traditional Successive Cancellation bit-Flipping(SCF) decoding algorithm only uses the absolute value of Log Like Ratio(LLR) to measure the reliability of information bit decoding results, which leads to a high Block Error Rate(BLER) and more attempts to flip.This paper proposes a SCF decoding algorithm named PLR-SCF.The causes of decoding errors in the SC decoding algorithm are analyzed, and simulation experiments are carried out to analyze the factors that lead to The First Decision Error(TFDE) of the SC decoding algorithm, including LLR, channel polarization reliability and the location of information bits.Based on these factors, a formula is designed to measure the decoding error of information bits.Simulation results show that compared with the traditional SCF decoding algorithm, the proposed decoding algorithm can reduce the BLER significantly.In the case of high Signal-to-Noise Ratio(SNR), the proposed algorithm displays a maximum SNR gain of 0.12 dB, and reduces the number of flip attempts and SCF by 13.6%.

Key words: polar code, Successive Cancellation bit-Flipping(SCF) decoding, Log-Likelihood-Ratio(LLR), The First Decision Error(TFDE), Block Error Rate(BLER)

中图分类号: 

• TN911.22