SCMA-based high-speed visible light communication system and adaptive coding and decoding method

Abstract

The invention provides a high-speed visible light communication system based on SCMA and a self-adaptive coding and decoding method, and relates to the technical field of wireless communication, and the communication system comprises a signal transmitting end which is used for carrying out codebook mapping and superposition on bit signal streams of a plurality of users to synthesize a four-dimensional complex signal stream, and carrying out the superposition transmission of the complex signal stream; the visible light channel is used for transmitting the complex signal flow; and the signal receiving end is used for receiving the complex signal stream transmitted through the visible light channel and decoding the complex signal stream to obtain an original bit signal stream. The invention aims to reduce the complexity of the original MPA decoding algorithm to the greatest extent on the premise of ensuring the decoding accuracy.

Description

technical field [0001] The present invention relates to the technical field of wireless communication, in particular to an SCMA-based high-speed visible light communication system and an adaptive encoding and decoding method. Background technique [0002] Following the development of 5G technology, people have focused their research on the next-generation mobile communication technology, namely 6G technology. The next-generation mobile communication technology is expected to use visible light communication and non-orthogonal multiple access technology. The advantages of visible light communication technology lie in its high security, good confidentiality, strong anti-electromagnetic interference ability, integration of communication and lighting functions, and no electromagnetic pollution. SCMA (Sparse Code Multiple Access, SCMA, Sparse Code Multiple Access) technology is a non-orthogonal multiple access technology in which multiple users share spectrum resources. It uses Lo...

AI Technical Summary

Problems solved by technology

Compared with the maximum likelihood algorithm (Maximum Likelihood, ML) detection method, although the algorithm complexity of the MPA decoder is reduced, its complexity increases exponentially with the increase of the number of users, which leads to low decoding efficiency and cannot meet the needs of the future. 6G System Deployment Requirements

In addition, for non-orthogonal multiple access multi-user detection, a technology called Serial Interference Cancellation (Successive interference cancellation, SIC) can also be used. Compared with MPA decoding technology, SIC decoding technology can greatly reduce its decoding complexity. A major disadvantage of the technology is that its decoding performance is not as good as that of MPA, especially at high signal-to-noise ratios

[0003] In view of the high complexity problems brought by the current MPA decoding algorithm, many improved MPA algorithms have been proposed, such as the MPA algorithm based on the logarithmic field, the MPA decoding algorithm based on the serial method, and the MPA algorithm based on partial codewords. Decoding algorithms and other algorithms that reduce the complexity of MPA decoding, it can be found that these algorithms are only improved on the basis of the original MPA decoding algorithm, and no other decoding strategy that is different from MPA is proposed. These improved algorithms are reducing the original MPA decoding algorithm. The complexity of the MPA decoding algorithm also reduces the performance of the receiver to a certain extent, indicating that these improved methods are sacrificing decoding accuracy in exchange for low complexity of the algorithm

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