分组马尔可夫叠加传输5G LDPC码的方案

doi:10.19665/j.issn1001-2400.2022.06.002

摘要/Abstract

摘要：

针对5G增强型移动宽带通信场景中数据信道的高可靠需求,提出了一种分组马尔可夫叠加传输5G LDPC码的方案。发送端首先将当前时刻待发送的传输块划分为多个码块,并分别编码为5G LDPC码字,之后将当前时刻的LDPC码字经过行列交织后叠加到下一个时刻的LDPC码字上,构成下一时刻的发送序列;接收端则可采用基于正规图的滑窗迭代译码算法进行译码。为降低译码的计算复杂度从而提升译码速度,方案借助协议中为每个码块分配的CRC校验,提出了一种提前终止译码准则,将通过校验码字在正规图中的对应信息固定,终止其更新。仿真结果表明,采用[1 056,528] 5G LDPC码作为基本码,在译码窗口大小仅为2的条件下,所提出的传输方案在BER=10^-6处与基本码相比有1.2 dB左右的性能增益,而进一步提高译码的窗口大小虽然能降低错误平层,但增益不明显。同时,在工作信噪比区域,所提方案的复杂度与基本码的接近。

关键词: 分组马尔可夫叠加传输, 低密度奇偶校验码, 5G

Abstract:

With the growing demand for high reliability in the enhanced mobile broadband (eMBB) scenario,we present a new class of block Markov superposition transmission codes using 5G low-density parity-check (LDPC) codes as the basic codes.At the transmitter,multiple code blocks (CBs) within a transport block (TB) are encoded separately by 5G LDPC codes,and then superimposed onto the following codewords of the next TB via a row/column interleaver.At the receiver,we present an iterative sliding-window decoding algorithm on a normal graph.Based on the cyclic redundancy check(CRC) in 5G protocols,we also employ a CRC-and-parity-check stopping criterion in the decoding algorithm,with which we can stop the updating procedure of specific codewords which has passed the check.Simulation results show that the proposed scheme using the 5G LDPC code[1 056,528] as the basic code can yield a coding gain of up to 1.2 dB over the conventional 5G LDPC code at the bit-error-rate of 10^-6,and that increasing the size of the decoding window has a limited effect on lowering the error floor.It is also revealed that the complexity of the proposed code is similar to the conventional 5G LDPC codes in the working SNR region.

Key words: block Markov superposition transmission, LDPC codes, 5G

中图分类号:

TN911.22

郭孔靖, 王千帆, 马啸. 分组马尔可夫叠加传输5G LDPC码的方案[J]. 西安电子科技大学学报, 2022, 49(6): 9-14.

GUO Kongjing, WANG Qianfan, MA Xiao. Block Markov superposition transmission of 5G LDPC codes[J]. Journal of Xidian University, 2022, 49(6): 9-14.

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