Ten Years of NOMA: Advances, Myths, and Open Challenges

Non-orthogonal multiple access (NOMA) has emerged as a key multiple access candidate for next-generation cellular networks, promising to support massive connectivity, enhance spectral efficiency, and reduce latency. Despite its academic popularity for a decade, practical challenges—such as successive interference cancellation (SIC) limitations and standardization hurdles—have hindered its adoption in 5G. This tutorial clarifies NOMA’s fundamental principles, debunks common misconceptions, and evaluates its real-world potential through experimental insights and state-of-the-art implementations. Critical discussions will address pivotal questions, including NOMA’s feasibility for IoT devices, the role of machine learning in interference-aware constellation design and resource optimization, and pathways toward 6G standardization. By exploring critical research directions—such as SIC-free decoding, autoencoder-based constellation designs, and distributed learning—the talk aims to bridge the gap between theoretical promise and practical deployment, shaping NOMA’s future as a transformative technology.