6G will enable a multitude of critical use cases, encompassing a wide range of essential applications and services with some shown in Figure 4. “5G, 6G, and Beyond: Recent Advances and Future Challenges”⁷ describes some of the latest advances and developments in 5G, 6G and beyond 6G systems. The article provides an in-depth investigation into the key technological enablers and use cases associated with these advanced wireless networks.

Figure 4 Use cases best served by 6G systems.⁶

GOALS AND TRENDS FOR BEYOND 6G COMMUNICATION

Terabit and petabit data rates: Beyond 6G aims to achieve even higher data rates compared to 6G. Terabit per second (Tbps) and petabit per second (Pbps) data rates are envisioned to support the growing demand for high speed communication, enabling applications like real-time 8K/16K video streaming, holographic communication and immersive virtual and augmented reality experiences. The article “Petabit-per-second Data Transmission using a Chip-scale Microcomb Ring Resonator Source”⁸ showcases 1.84 Pbps transmission rates over a 37-core, 7.9 km fiber using 223 wavelength channels derived from a single microcomb ring resonator. This resonator generates a stabilized dark-pulse Kerr frequency comb. Additionally, the theoretical analysis suggests that a solitary, chip-scale light source has the potential to support data transmission systems with massively parallel space- and wavelength-multiplexing at a rate of 100 Pbps.

Intelligent and cognitive networks: Beyond 6G will further leverage AI and ML techniques to create intelligent and cognitive networks. These networks will be capable of self-optimization, self-healing and self-adaptation to dynamically changing network conditions, user requirements and traffic patterns. “Sixth Generation (6G) Cognitive Radio Network (CRN) Application, Requirements, Security Issues, and Key Challenges”⁹ provides an overview of the forthcoming generation of cognitive radio (CR) network communication. It discusses the mandatory cases for its evolution, highlights the present technology improvement efforts and presents a detailed perspective on the future advancements in this field. Figure 5 shows a potential scenario for using 6G CR in data transmission networks.

Figure 5 A possible scenario for 6G CR network communication.⁹

Enhanced spectrum utilization: Beyond 6G will explore innovative spectrum utilization techniques to address the growing spectrum scarcity. This may involve leveraging higher frequency bands, such as the THz range, as well as developing advanced spectrum-sharing mechanisms to efficiently allocate and utilize the available spectrum resources. “Beyond 5G: Big Data Processing for Better Spectrum Utilization”¹⁰ highlights the immense potential of big data processing in enabling advanced user- and situation-oriented resource utilization in future wireless networks. Specifically, it explores the utilization of detailed and content-rich maps and records known as Radio Service Maps to unlock spectrum opportunities in 6G networks.

Seamless integration of physical and virtual worlds: Beyond 6G aims to close the divide between the physical and virtual realms, enabling seamless integration of digital information and physical environments. This may involve advancements in the IoT, cyber-physical systems, edge computing and the tactile Internet to create a highly interactive and immersive communication experience.

Ubiquitous and hyperconnected networks: Beyond 6G envisions hyperconnected networks that seamlessly integrate various communication technologies, including terrestrial networks, satellite networks, aerial platforms and even space-based communication systems. These networks will provide ubiquitous connectivity, enabling seamless communication anytime and anywhere. “Towards 6G Hyper-Connectivity: Vision, Challenges, and Key Enabling Technologies”¹¹ provides an overview and analysis of the hyperconnected architecture of 6G networks, highlighting its key components, addressing the current challenges and exploring potential areas for future research and development. The fundamental principles of hyperconnectivity in 6G are visually depicted in Figure 6.

Figure 6 Vision of 6G hyperconnectivity.¹¹

Quantum communication: Beyond 6G may incorporate quantum communication technologies, harnessing the principles of quantum mechanics to provide secure and fast communications. Quantum key distribution (QKD) and quantum teleportation are potential applications that could enhance security and enable new communication paradigms. As cellular systems progress from 5G to 6G, there has been significant advancement in quantum information technology (QIT), particularly in quantum communications and quantum computing. QKD, for instance, can strengthen 6G security by enabling secure quantum communications. “Quantum-Enabled 6G Wireless Networks: Opportunities and Challenges”¹² offers a technology-driven and forward-thinking depiction and investigation of how QIT can be harnessed for the advancement of future 6G wireless networks. Figure 7 illustrates a quantum-enabled 6G system, where QIT is exploited to realize new 6G functionalities and services.

Figure 7 A possible quantum-enabled 6G system.¹²

Green and sustainable networks: Energy efficiency and sustainability will continue to be important considerations in beyond 6G networks. Energy-efficient hardware designs, renewable energy integration and intelligent power management techniques will be employed to reduce the environmental impact of wireless communication systems. “Shaping Future 6G Networks: Needs, Impacts, and Technologies”¹³ introduces a comprehensive approach to achieving green 6G, emphasizing the role of AI in this context. It highlights the advantages of employing AI in wireless networks, considering the energy requirements for AI training and inference.

CONCLUSION

While specific standards and technologies for beyond 6G are yet to be defined, this article and its references provide a glimpse into the potential directions and aspirations for future wireless communication systems beyond the anticipated 6G era. Terabit wireless communication aims to provide a fiber-like experience over wireless networks, offering seamless connectivity, fast downloads and low latency connections. This creates opportunities for real-time streaming of high-resolution videos, immersive virtual reality experiences and rapid data transfer for applications like autonomous vehicles and smart cities. In conclusion, next-generation terabit wireless communication advancements beyond 6G hold tremendous promise for revolutionizing the ways to connect, communicate and experience the digital world. The realization of terabit wireless communication will bring all closer to a fully connected world where data flows seamlessly, enabling new possibilities and transformative applications across various sectors.

References

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For Further Reading

Y. Zhang and C. Liu, ”5G Ultra-dense Network Fingerprint Positioning Method based on Matrix Completion,” China Communications, Vol. 20, No. 3, March 2023.

Md. Y. Ali, T. Hossain and Md. M. Mowla, “A Trade-off between Energy and Spectral Efficiency in Massive MIMO 5G System,” International Conference on Electrical, Computer & Telecommunication Engineering (ICECTE), 2019.

M. Barbuto, Z. Hamzavi-Zarghani, M. Longhi and A. Mont, “Metasurfaces 3.0: A New Paradigm For Enabling Smart Electromagnetic Environments,” IEEE Transactions on Antennas and Propagation, Vol. 70, No. 10, October 2022.

V. Ziegler; H. Viswanathan; H. Flinck, “6G Architecture to Connect the Worlds,” IEEE Access, Vol. 8.