SCMA with Low Complexity Symmetric Codebook Design for Visible Light Communication

TL;DR

This paper proposes a symmetric codebook design for SCMA in VLC systems, reducing complexity and improving performance by maximizing Euclidean distance and enabling fast convergence.

Contribution

It introduces a low-complexity symmetric codebook design for SCMA tailored to VLC, enhancing detection efficiency and system performance.

Findings

Outperforms existing VLC-modified SCMA codebooks in simulations

Reduces design and detection complexity

Achieves fast convergence with fewer iterations

Abstract

Sparse code multiple access (SCMA) is attracting significant research interests currently, which is considered as a promising multiple access technique for 5G systems. It serves as a good candidate for the future communication network with massive nodes due to its capability of handling user overloading. Introducing SCMA to visible light communication (VLC) can provide another opportunity on design of transmission protocols for the communication network with massive nodes due to the limited communication range of VLC, which reduces the interference intensity. However, when applying SCMA in VLC systems, we need to modify the SCMA codebook to accommodate the real and positive signal requirement for VLC.We apply multidimensional constellation design methods to SCMA codebook. To reduce the design complexity, we also propose a symmetric codebook design. For all the proposed design approaches, the minimum Euclidean distance aims to be maximized. Our symmetric codebook design can reduce design and detection complexity simultaneously. Simulation results show that our design implies fast convergence with respect to the number of iterations, and outperforms the design that simply modifies the existing approaches to VLC signal requirements.