An ultra-reliable low-latency non-binary polar coded SCMA scheme

Li, S., Cai, M., Jin, L., Sun, Y. , Wu, H. and Wang, P. (2022) An ultra-reliable low-latency non-binary polar coded SCMA scheme. IEEE Transactions on Vehicular Technology, 71(6), pp. 6518-6533. (doi: 10.1109/TVT.2022.3164902)

Abstract

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.

• Item Type: Articles
• Additional Information: This work was supported in part by the National Natural Science Foundation of China under Grant 61601414, and in part by the Fundamental Research Funds for the Central Universities under Grant CUC210B032.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Sun, Dr Yao
• Authors: Li, S., Cai, M., Jin, L., Sun, Y., Wu, H., and Wang, P.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Journal Name: IEEE Transactions on Vehicular Technology
• Publisher: IEEE
• ISSN: 0018-9545
• ISSN (Online): 1939-9359
• Published Online: 05 April 2022
• Copyright Holders: Copyright © 2021 IEEE
• First Published: First published in IEEE Transactions on Vehicular Technology 71(6): 6518-6533
• Publisher Policy: Reproduced in accordance with the publisher copyright policy