A Modified BP Bit-Flipping Algorithm for Polar Codes
Lijuan Li, Hangxuan Cui, Yangcan Zhou, Zhongfeng Wang · 2022
The belief propagation (BP) algorithm for polar codes has attracted significant attention due to its soft-output property and high parallelism. However, the BP algorithm is not comparable with the successive cancellation list (SCL) algorithm in terms of the error-correction performance. In this paper, we propose a high-stage BP flip (HSBPF) algorithm to further improve the error-correction performance of the BP algorithm by analyzing the distribution of log-likelihood ratio (LLR) values. Simulation results show that the decoding latency can be reduced by 30% with the proposed algorithm. Moreover, benefiting from the simplified message passing of the factor graph, the computational complexity of the proposed algorithm is also significantly reduced compared with the existing algorithms.