Researchers at Fudan University argue that visible light communication has evolved and will become a cornerstone of 6G, the next generation of wireless connectivity.
In a review published in the Opto-Electronic Technology journal, the scholars detail a future where Space-Air-Ground-Sea Integrated Networks (SAGSINs) use the visible spectrum to achieve data rates hundreds of times faster than current technologies. The study was led by Professor Nan Chi.
“The explosive growth of data-intensive applications, such as 4K/8K video streaming, augmented and virtual reality, the Internet of Things, artificial intelligence, and digital twins, has resulted in traffic demands several orders of magnitude higher than those of traditional text and voice services,” the authors wrote.
One important part of the solution, according to them, is a combination of 6G and Visible Light Communication (VLC).
The visible light spectrum, the researchers said, offers spectral resources approximately four times larger than commonly used wireless bands.
Beyond its sheer volume, VLC is supposed to be energy-efficient, “inherently secure,” and immune to the electromagnetic interference that traditional radio systems struggle with.
From Light Bulbs to High-Speed Lasers
While early VLC systems were often designed to piggyback on standard LED lighting, the study highlighted a significant shift in technology. Modern research has moved toward the idea of high-bandwidth laser-based transmitters.
“These configurations are primarily intended for dedicated scenarios such as data centre interconnects, underwater directional links, and inter-satellite communications, where illumination functionality is not required,” the study showed.
Technological breakthroughs in device architecture have already pushed transmission limits to staggering heights. While single-wavelength point-to-point systems have reached 36.5 Gbps, experimental systems using multi-wavelength multiplexing have successfully exceeded 600 Gbps and even 800 Gbps, according to the survey.
AI: The New Signal Processor
One of the primary hurdles for light-based data is signal distortion caused by environmental factors like atmospheric turbulence or underwater scattering. To counter this, the authors suggested the integration of Artificial Intelligence into VLC systems.
The study details “learning-assisted post-equalisers” that use neural networks to predict and compensate for nonlinear distortions in real-time. These AI-driven frameworks can learn the characteristics of a communication channel in a data-driven manner, maintaining high performance even in rapidly changing environments.
A Multidimensional Vision: Space and Sea
According to the researchers, the roadmap for VLC extends beyond terrestrial internet access. The study identifies key domains where light-based communication will be transformative:
- Space Networks: VLC suits inter-satellite links because it is resistant to high-energy radiation and features low beam divergence, allowing for stable communication over vast distances.
- Marine Environments: Because blue-green light can penetrate water more effectively than radio waves, VLC is a candidate for high-speed underwater networks connecting autonomous vehicles and sensor arrays.
- Data Centres: To handle the massive data exchange of modern cloud computing, VLC offers low-latency, “cable-free” interconnects between server racks.
- Vehicular Networks (V2X): The high-speed, flexible nature of light can support autonomous driving and intelligent transportation systems.
The Path to Integration
The authors said that “overall, progressive field validations indicate that VLC has established a solid technical foundation for real-world deployment.”
However, despite the promising speeds, several challenges remain before VLC becomes as ubiquitous as Wi-Fi.
The researchers pointed out the need for “visible-light photonic integration”—essentially shrinking complex optical components onto silicon chips that are compatible with existing semiconductor manufacturing.
Besides, while laboratory results are impressive, real-world deployments must account for unpredictable factors like weather and physical blockages. The study calls for “perception-driven predictable communication,” where systems can sense environmental changes and adjust their beams autonomously.
“Advances along these directions are expected to unlock new application scenarios, ranging from space communications and integrated sensing-communication systems to ultra-high-capacity optical interconnects, ultimately positioning VLC as a key enabling technology in future wireless networks,” the study concludes.
This article was written with the assistance of AI
