Abstract
Sparse code multiple access (SCMA) has been proposed to obtain high capacity and support massive connections. When combined with the multiple‐input multiple‐output (MIMO) techniques, the spectrum efficiency of the SCMA system can be further improved. However, the detectors of the MIMO‐SCMA system have high computational complexity. For the maximum likelihood (ML) detection, though it is optimal decoding algorithm for the MIMO‐SCMA system, the detection complexity would grow exponentially with the number of both the antennas and users increase. In this paper, we consider a space‐time block code (STBC) based MIMO‐SCMA system where SCMA is used for multiuser access. Besides, we propose a low‐complexity utilizing joint message passing algorithm (JMPA) detection, which narrowing the range of superimposed constellation points, called joint message passing algorithm based on sphere decoding (S‐JMPA). But for the S‐JMPA detector, the augment of the amount of access users and antennas leads to the degradation of decoding performance, the STBC is constructed to compensate the performance loss of the S‐JMPA detector and ensure good bit error rate (BER) performance. The simulation results show that the proposed method achieves a close error rate performance to ML, JMPA, and a fast convergence rate. Moreover, compared to the ML detector, it also significantly reduces the detection complexity of the algorithms.
Highlights
The IMT-2020 Promotion Group has stated that the mobile Internet and mobile Internet of Things (IoT) will become the main driving forces for the development of mobile communication in the future [1]
In the downlink multiple-input multiple-output (MIMO)-Sparse code multiple access (SCMA) system based on space-time block code (STBC), the S-JMPA algorithm based on the joint message passing algorithm selects the codeword information with a high belief value to reduce the decoding complexity [21]
We provide some simulation results and numerical results to evaluate the performance of the proposed MIMO-SCMA system and compare three schemes to verify the performance of the proposed algorithm: the maximum likelihood (ML) decoding algorithm, the original JMPA, and the JPMA without STBC
Summary
Xinjiang Key Laboratory of Signal Detection and Processing, College of Information Science and Engineering, Xinjiang University, Urumqi 830046, China. Sparse code multiple access (SCMA) has been proposed to obtain high capacity and support massive connections. The detectors of the MIMO-SCMA system have high computational complexity. For the maximum likelihood (ML) detection, though it is optimal decoding algorithm for the MIMO-SCMA system, the detection complexity would grow exponentially with the number of both the antennas and users increase. We propose a lowcomplexity utilizing joint message passing algorithm (JMPA) detection, which narrowing the range of superimposed constellation points, called joint message passing algorithm based on sphere decoding (S-JMPA). For the S-JMPA detector, the augment of the amount of access users and antennas leads to the degradation of decoding performance, the STBC is constructed to compensate the performance loss of the S-JMPA detector and ensure good bit error rate (BER) performance. Compared to the ML detector, it significantly reduces the detection complexity of the algorithms
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
