6G mobile communication networks: vision, challenges, and key technologies

While scaled-up commercial 5G networks are currently being deployed around the world, increasing numbers of researchers and organizations have already begun to consider the next generation of mobile communication systems. This article explores the 6G concept for the 2030s and provides some directional guidance for subsequent research. The vision for future 6G systems is characterized by the key terms, "Intelligent Connectivity," "Deep Connectivity," "Holographic Connectivity," and "Ubiquitous Connectivity," which constitute the overall slogan of "Wherever you think, everything follows your heart." The technical requirements and challenges, including peak throughput, higher energy efficiency, connection everywhere and every time, new theories and technologies, self-aggregating communication fabrics, and some non-technical challenges, of realizing this vision are analyzed. Then, the potential key technologies are classified and presented: communication technologies on new spectrums, including terahertz and visible light communications; fundamental technologies, including sparse theory (compressed sensing), new channel coding technology, large-scale antenna, flexible spectrum usage, and AI-based wireless communications; special technical features, including Space-Air-Ground-Sea integrated communications and wireless tactile networks.