Fluid Antenna Multiple Access for 6G: A Holistic Review

Future wireless networks must deliver unprecedented spectral efficiency to accommodate massive numbers of interconnected devices; yet today’s multiple-access schemes remain fundamentally constrained by interference. Fluid antenna multiple access (FAMA) has emerged as a promising paradigm that tackles this bottleneck by introducing a new degree of freedom (DoF): receiver-side spatial fluidity enabled by fluid antenna systems (FAS). By dynamically repositioning the FAS aperture to exploit fine-grained channel variations, FAMA can mitigate inter-user interference and enable massive multiple access on the same time-frequency resource without precoding and any other interference suppression techniques. This paper presents a comprehensive survey of recent advances in FAMA. We first summarize the operating principles of FAS and then formalize FAMA, including representative network and channel models. We systematically categorize and review FAMA architectures—fast FAMA, slow FAMA, compact ultra-massive antenna arrays (CUMA), coded FAMA, and turbo FAMA—highlighting their design rationales, performance benefits, and applicability regimes. We further discuss practical considerations such as channel acquisition and tracking, hardware constraints, switching/positioning overhead, and integration with existing air interfaces. Finally, we outline open challenges and future research directions, including scalable resource allocation, robustness under mobility and correlation, protocol/standardization aspects, and cross-layer co-design. Overall, this survey provides a unified framework to understand FAMA’s potential and to guide both academic research and industrial innovation in this rapidly evolving area.