Research On New Multi-access Transmission Technology For 6G

Unsourced Multiple Access(UMAC)is a novel multi-user communication technology that enables multiple users to access a channel without the need for user identification or data transmission,using a unique coding scheme that does not require decoding.UMAC has a wide range of potential applications in various wireless communication scenarios,such as the Internet of Things,communication perception,and group communication in the 6th generation mobile networks(6G).Currently,UMAC has attracted significant research interest,with the primary focus on code design,channel coding,channel estimation,and multi-user detection.The core of UMAC lies in the design of short code-length channel codes with excellent performance.Therefore,this study mainly explores channel coding techniques for the next-generation mobile communication technology and a UMAC framework based on spread spectrum anti-interference mechanisms,discussing the directions and challenges for future research.Specifically,this study focuses on the following aspects:Firstly,this study investigated the polar code coding technique used in the 5th generation mobile communication technology.As the 6G technology is developed,and high-speed and low-latency applications emerge,polar code design and usage face new challenges.Polar codes for 5G suffer from performance degradation due to incomplete channel polarization when using short codes.To address this challenge,this study proposes Polarization-Adjusted Convolutional(PAC)coding,which can effectively meet the application requirements of UMAC in 6G.Through theoretical analysis,this study proposes a joint boundary construction method based on the Hamming distance spectrum,which has better performance than the traditional PAC code construction algorithm and can achieve better performance under code length constraints,thus matching UMAC technology.Furthermore,based on the above research on error-correcting codes,this study further investigates unsourced multiple access technology based on spread spectrum,which can effectively meet the requirements of massive machine-type communications(m MTC)in 6G.In addition,through the combination of the UMAC system and PAC code,simulation results demonstrate that the new system can improve user identification accuracy and reduce time and space complexity compared to traditional polar code-based UMAC systems.Finally,applying the joint boundary construction method proposed in this study to the UMAC system validates that the algorithm can further improve the system’s detection performance.In summary,this study proposes a series of coding and waveform construction methods with better performance for UMAC system optimization design,targeting unsourced multiple access technology for the next generation of mobile communications from the perspectives of error-correcting coding and multiple access construction.