Multi‐Dimensional Multiple Access for 6G: Efficient Radio Resource Utilization and Value‐Oriented Service Provisioning

Embarking on the 6G era, the next‐generation multiple access techniques are facing critical challenges of enhancing massive connectivity, satisfying diverse service requirements, and empowering heterogeneous application scenarios and vertical industries using extremely constrained radio resources. In addressing these challenges, this chapter presents an intelligent and flexible multiple‐access technique, multi‐dimensional multiple access (MDMA), which amalgamates different multiple access schemes in a generalized paradigm with enhanced radio resource utilization efficiency. The chapter elucidates the fundamental objectives, designing principles, and implementation details of MDMA, emphasizing its ability to accommodate individualized quality‐of‐service (QoS) provisioning and facilitate the value‐oriented network operation. Furthermore, the optimization objectives for the envisioned value‐realization of 6G networks are elaborated with in‐depth details. Finally, this chapter presents the performance comparison between MDMA and state‐of‐the‐art multiple‐access techniques, which validates the superiority and effectiveness of MDMA with both individual‐level and system‐level evaluations.