5G抽头延迟模型中极化译码后处理方案

Post-processing scheme for polar decoding in 5G tap delay model

考虑5G协议中的抽头延迟信道模型,针对分段循环冗余比特自适应(SCAD-SCL)极化译码算法未考虑信噪比对接收序列对数似然比影响的问题,提出SCAD-SCL的后处理(PSCAD-SCL)译码算法。通过仿真确定用于提高可靠性设定的常数和不可靠对数似然比的数目,翻转并适当放大不可靠的对数似然比值,从而提高误比特率性能。仿真结果表明,PSCAD-SCL的误比特率在信噪比1~3 dB优于原有SCAD-SCL译码算法。在误比特率为10-4时PSCAD-SCL较SCAD-SCL算法性能提升了约0.3 dB,提出算法能够提升5G传输性能。

Considering the tap delay channel model in 5G protocol,and aiming the problem that the segmented cyclic redundancy bit adaptive(SCAD-SCL)polarization decoding algorithm does not consider the influence of SNR on the log-likelihood ratio of the received sequence,this paper proposed the post-processing(PSCAD-SCL)decoding algorithm for SCAD-SCL.The algorithm determined the number of constant and unreliable log-likelihood ratio used to improve the reliability setting through simulation,and fliped and appropriately enlarged the unreliable log-likelihood ratio to improve the bit error rate performance.The simulation results show that the bit error rate of PSCAD-SCL is better than the original SCAD-SCL decoding algorithm in the signal-to-noise ratio of 1~3 dB.When the bit error rate is 10-4,the performance of PSCAD-SCL algorithm is about 0.3 dB higher than that of the SCAD-SCL algorithm.The proposed algorithm can improve 5G transmission performance.