Successive Cancellation List Algorithm Based on Path Metric in Polar Code Decoding
Shufeng Li, Baoxin Su, Yu Guo, Mingyu Cai · 2023
Path Metric (PM) is the reference standard for decoding path reliability in successive cancellation list (SCL) algorithm, which needs to be updated in real time with the verdict of bits, and is the main component of decoding complexity of the SCL algorithm in addition to the recurrence of log-likelihood ratio (LLR) information. Most schemes for optimizing the decoding complexity of the SCL algorithm focus on reducing the recurrence of LLR, and relatively little research has been done on reducing the computational complexity of PM. Based on this current situation, this paper proposes an optimization scheme for the SCL algorithm flow by analyzing the execution process and the role of PM in the SCL algorithm. Meanwhile, the optimized simplified SCL based double-repetition nodes (SSCL-D-Rep) algorithm is proposed for the phenomenon of increasing PM computation in the SSCL algorithm and the SSCL-D-Rep algorithm. Simulation results show that the SSCL-D-Rep algorithm proposed in this paper can reduce the system complexity without losing the bit error rate (BER).