Low complexity receiver of sparse code multiple access based on dynamic trellis. Issue 9 (1st June 2020)

• Record Type: Journal Article
• Authors: Peng, Xiaohuan; Pan, Zhipeng; Lai, Ke; Wen, Lei; Lei, Jing
• Is Part Of: IET communications. Volume 14:Issue 9(2020)
• Page Start: 1420
• Page End: 1427
• Publication Date: 2020-06-01
• Subjects: multiuser detection -- error statistics -- multi‐access systems -- message passing -- trellis codes -- 5G mobile communication -- communication complexity -- wireless channels -- iterative methods -- radio receivers; message passing algorithm -- computational complexity -- SCMA schemes -- CAD‐EML‐MPA -- DT‐MPA -- low complexity receiver -- sparse code multiple access schemes -- nonorthogonal multiple access schemes -- high spectral efficiency -- channel‐adaptive extended max‐log MPA -- 5G communications -- multiuser detection -- dynamic trellis based MPA -- bit error rate performance; Telecommunication systems -- Periodicals; Speech processing systems -- Periodicals; 621.38205
• DOI: 10.1049/iet-com.2019.0719
• Languages: English
• ISSNs: 1751-8628

Abstract

Abstract : Sparse code multiple access (SCMA) is one of the non‐orthogonal multiple access schemes to meet the demands of massive connection and high spectral efficiency in the 5G communications. Since the sparsity of the codebook, the message passing algorithm (MPA) can be utilised for multi‐user detection. However, the high computational complexity of MPA hinders the practical application of SCMA. The extended Max‐Log MPA (EML‐MPA) and the channel‐adaptive extended Max‐Log MPA (CAD‐EML‐MPA) help to reduce the complexity of conventional Log‐MPA with trellis representation. On this basis, the authors propose a dynamic trellis based MPA (DT‐MPA) in this study. DT‐MPA selects symbols dynamically according to a specific threshold τ in each iteration of MPA. The impact of the threshold on the complexity and convergence behaviour is analysed. Simulation results show that the DT‐MPA with variable τ which is related to bit signal‐to‐noise can achieve better bit error rate performance and lower complexity than EML‐MPA and CAD‐EML‐MPA.