{"title":"Random Spreading With Higher Order Modulation in Unsourced Random Access","authors":"Jian Dang;Zaichen Zhang;Yongpeng Wu","doi":"10.1109/LCOMM.2025.3544250","DOIUrl":null,"url":null,"abstract":"Unsourced random access (URA) is crucial for future massive access scenarios. Existing URA schemes often use low-order modulation and assess performance with a limited number of active users. This work presents a pilot-free URA scheme that employs random spreading and higher-order modulation. We derive a discrete mixture generalized approximate message passing algorithm to enhance active user detection (AUD) and data detection. Simulations show that our proposed method significantly outperforms pilot-based methods in AUD, and higher-order modulation supports a large number of active users while ensuring the target per user probability of error (PUPE) performance.","PeriodicalId":13197,"journal":{"name":"IEEE Communications Letters","volume":"29 4","pages":"829-833"},"PeriodicalIF":3.7000,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IEEE Communications Letters","FirstCategoryId":"94","ListUrlMain":"https://ieeexplore.ieee.org/document/10897967/","RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"TELECOMMUNICATIONS","Score":null,"Total":0}
引用次数: 0
Abstract
Unsourced random access (URA) is crucial for future massive access scenarios. Existing URA schemes often use low-order modulation and assess performance with a limited number of active users. This work presents a pilot-free URA scheme that employs random spreading and higher-order modulation. We derive a discrete mixture generalized approximate message passing algorithm to enhance active user detection (AUD) and data detection. Simulations show that our proposed method significantly outperforms pilot-based methods in AUD, and higher-order modulation supports a large number of active users while ensuring the target per user probability of error (PUPE) performance.
期刊介绍:
The IEEE Communications Letters publishes short papers in a rapid publication cycle on advances in the state-of-the-art of communication over different media and channels including wire, underground, waveguide, optical fiber, and storage channels. Both theoretical contributions (including new techniques, concepts, and analyses) and practical contributions (including system experiments and prototypes, and new applications) are encouraged. This journal focuses on the physical layer and the link layer of communication systems.