An Ultra-Reliable Low-Latency Non-Binary Polar Coded SCMA Scheme

作     者：Li, Shufeng Cai, Mingyu Jin, Libiao Sun, Yao Wu, Hongda Wang, Ping 

作者机构：Commun Univ China Sch Informat & Commun Engn State Key Lab Media Convergence & Commun Beijing 100024 Peoples R China Univ Glasgow James Watt Sch Engn Glasgow G12 8QQ Lanark Scotland York Univ Lassonde Sch Engn Dept Elect Engn & Comp Sci Toronto ON M3J 1P3 Canada 

出 版 物：《IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY》 (IEEE Trans. Veh. Technol.)

年 卷 期：2022年第71卷第6期

页      面：6518-6533页

核心收录：

学科分类：0810[工学-信息与通信工程] 0808[工学-电气工程] 08[工学] 0823[工学-交通运输工程] 

基　　金：National Natural Science Foundation of China Fundamental Research Funds for the Central Universities [CUC210B032] 

主　　题：Receivers Decoding Iterative decoding Encoding Modulation Bit error rate Ultra reliable low latency communication Polar codes SCMA ultra-reliable low-latency communication multiuser receiver joint iterative detection and decoding 

摘      要：The joint transmission scheme of polar codes and sparse code multiple access (SCMA) has been regarded as a promising technology for future wireless communication systems. However, most of the existing polar-coded SCMA (PC-SCMA) systems suffer from high latency caused by the feedback iteration and list decoding. In addition, the error performance of PC-SCMA systems is unsatisfactory for ultra-reliable transmission. Inspired by the compelling benefits of non-binary polar codes, in this paper, we design a non-binary polar-coded SCMA (NB-PC-SCMA) system with a free order matching strategy to address the issues of delay and reliability. Specifically, we first formulate a joint factor graph for NB-PC-SCMA and propose a non-binary successive cancellation list (NB-SCL) and damping based joint iterative detection and decoding (NSD-JIDD) multiuser receiver to improve the BER and latency performance. Then, a lazy-search based NB-SCL (L-NB-SCL) decoding is proposed to reduce the computational complexity by simplifying the path search pattern of the list decoder. After that, we modify the update of user nodes for SCMA detection to improve the convergence error and finally propose the improved NSD-JIDD (ISD-JIDD) algorithm, which can avoid redundant operations by exploiting L-NB-SCL decoding. Simulation results show that the proposed NB-PC-SCMA system achieves better bit error rate (BER) performance and considerable latency gain when compared to its counterparts. In particular, the proposed ISD-JIDD can achieve similar BER performance of NSD-JIDD with less complexity.