Emerging Trends in Massive Access Techniques for B5G and 6G Networks: A Concise Review

This review paper provides an overview of various multiple access schemes proposed to meet the massive access (MA) demands of Beyond 5G (B5G) and 6G networks. Initially, it elucidates the challenges associated with MA compared to traditional access methods and discusses several promising MA schemes, detailing their mechanisms. This encompasses an exploration of various Non-Orthogonal Multiple Access (NOMA) schemes such as Sparse Code Multiple Access (SCMA) and MultiUser Shared Access (MUSA), as well as energy-efficient schemes like tensor-based (TB) methods, coded compressed sensing, and uncoupled compressed sensing. The paper also reviews and compares some of the results obtained in existing literature. Finally, it summarizes the latest advancements in MA, presenting them in a comprehensive table.