Vol. 14, no.3, 2022


QR-decomposition based receivers for downlink MIMO-SCMA

Islam Kanatbekuli, Dmitriy A. Pokamestov, Yakov V. Kryukov, Eugeniy V. Rogozhnikov, Renat R. Abenov

Tomsk State University of Control Systems and Radioelectronics, https://tusur.ru/ru/
Tomsk 634050, Russian Federation
E-mail: islam-mabad@bk.ru, dmaltomsk@mail.ru, kryukov.tusur@gmail.com, udzhon@mail.ru, abenov.rr@gmail.com

Received 24.06.2022, peer-reviewed 30.06.2022, accepted 07.07.2022

Abstract:: For the signal receiver of multiantenna communication systems, various multiple access schemes based on sparse SCMA (Sparse Code Multiple Access) codes are considered, applied in conjunction with MIMO (Multiple Input-Multiple Output) multiantenna systems, which make it possible to provide a high level of noise immunity and spectral efficiency of communication and network connections, being the basis of a possible concept for organizing the physical layer of 6G networks. Various MIMO-SCMA schemes are considered and the main stages of signal generation and processing are given. One of the problems in the implementation of MIMO-SCMA is the high computational complexity of signal processing algorithms in the receiver. To solve this problem, it is proposed to use QR decomposition for MIMO decoding in the MIMO-SCMA scenario. It is shown that this method allows not only to significantly reduce the computational complexity due to received signal transformations, but also to provide higher noise immunity compared to classical approaches. The results are obtained using the message passing algorithm for various MIMO coding schemes and antenna system configurations.

Keywords: NOMA access methods, SCMA codes, MIMO systems, 5G and 6G standards, QR decomposition

UDC 621.396.4

RENSIT, 2022, 14(3):291-300e DOI: 10.17725/rensit.2022.14.291.

Full-text electronic version of this article - web site http://en.rensit.ru/vypuski/article/457/14(3)291-300e.pdf