An interference-reducing precoding for SCMA multicast design based on complementary sequences

Li, S., Yu, X., Sun, Y. , Jin, L. and Xia, Z. (2022) An interference-reducing precoding for SCMA multicast design based on complementary sequences. IEEE Transactions on Broadcasting, 68(4), pp. 848-861. (doi: 10.1109/TBC.2022.3201637)

Abstract

In a multi-group multicast sparse code multiple access (SCMA) system, one base station multicasts common messages to multiple multicast groups via different code books. To accommodate more user terminals (UTs), traditional multicast systems have multiple transmitters, each of which works in one-to-many mode. In this way, each UT is subject to inter-transmitter interference. Considering the high degrees of freedom for transmitting and receiving, it is difficult to separate the desired signal from interference signals. Therefore, an interference-reducing precoding scheme is required to ensure the reliability of SCMA multicast communication system. For the SCMA multicast system design, we present three necessary conditions that the interference-reducing matrix should satisfy. Then, the precoding matrix satisfying the three necessary conditions simultaneously is designed by utilizing the complementary sequences (CS) and complete complementary sequences (CCS). In this context, we consider two scenarios with different transmission modes (single-cell and multiple-cell) and different precoding schemes (based on CS and CCS). Simulation results show that proposed transmission schemes can significantly reduce the bit error rate of multicast groups while ensuring the communication throughput, and behave a superior performance over other alternatives. Moreover, theoretical and simulation results also prove that the proposed precoding vectors have perfect average power radiation and omnidirectional coverage performance.

• Item Type: Articles
• Additional Information: This work was supported 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., Yu, X., Sun, Y., Jin, L., and Xia, Z.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Journal Name: IEEE Transactions on Broadcasting
• Publisher: IEEE
• ISSN: 0018-9316
• ISSN (Online): 1557-9611
• Published Online: 07 September 2022
• Copyright Holders: Copyright © 2022 IEEE
• First Published: First published in IEEE Transactions on Broadcasting 68(4): 848-861
• Publisher Policy: Reproduced in accordance with the publisher copyright policy