YOFC’s recent field trials with major telecom operators in China have set new global benchmarks for data transmission speed, capacity, and latency reduction. Hollow core fibre has significant potential to shape the next generation of fibre transmission in the era of artificial intelligence and high-performance computing.

Improving Optical Transmission with HFC

Traditional solid-core optical fibres transmit light through glass. However hollow-core fibre offers a new approach to data transmission in optical networks. In YOFC's advanced hollow-core design light travels through air in a hollow center. A special microstructure surrounds this center to maintain signal quality.

The science behind this method is important because it changes the physical rules that control signal transmission. Light moves about 31% slower in glass than in air or a vacuum. By using air to guide signals, hollow-core fibres achieve:

  • Signals that travel 47% faster than in regular fibres
  • About 31% less delay over the same distance
  • Signal degradation has seen a major reduction, with attenuation reaching as low as 0.05dB/km in recent tests
  • Nonlinear optical effects that limit transmission capacity have almost disappeared

Technical Architecture and Manufacturing Breakthroughs

YOFC's innovations center on their unique Hollow-core Anti-Resonant Fibre (HC-ARF) design with a supporting tube structure (ST-HCF). This design creates an optimised air-core surrounded by capillaries placed with precision to maintain optical confinement through anti-resonant reflection.

To make hollow-core fibre on an industrial scale presents huge challenges that YOFC has overcome through several key breakthroughs:

  • Specialised Raw Materials: YOFC has created self-made materials to optimise hollow-core structures. This ensures unmatched purity and better performance.
  • Precision Capillary Production: The company uses cutting-edge manufacturing methods to make capillaries. These have the same dimensions at the nanometer level, which is key to maintain optical performance across miles of fibre.
  • Advanced Drawing Process: YOFC has come up with new drawing techniques. These keep the fragile hollow-core structure intact while producing continuous fibre lengths over 20 kilometers. This is crucial for real-world network setup.
  • Environmental Protection: Special manufacturing steps control humidity and prevent contamination during production. This is necessary because even tiny particles can affect hollow-core performance.

We appreciate the achievements of the team at YOFC for their laboratory research, real-world demonstrations, and growing manufacturing capacity for scale.

Record-Breaking Field Demonstrations

World's First 800G Hollow-Core Fibre Network

In June 2024, YOFC and China Mobile showed off the world's first 800G hollow-core fibre transmission test network in Shenzhen-Dongguan, Guangdong Province. This big step included a full 20km test link with hollow-core fibre cables that could send data both ways with a total throughput of 128Tb/s.

The test showed:

  • 800Gbps single-wavelength optical transmission across the whole 20km network
  • Two-way operation with special end equipment
  • New splicing methods to connect hollow-core parts and link with existing solid-core systems
  • Live traffic control proving it could work in real life

China Mobile's network engineers put specialied cable handling methods into action to stop environmental contamination as they rolled out their field operations. The cable used several groundbreaking waterproofing fixes such as water-blocking glue and double-layer plastic caps at cable ends to cut off the atmosphere, specialied pulling units with swivels to reduce wear on protective end caps, and horizontal waterproof cable closures where fusion splices occurred.

YOFC HFC Fibre Demonstrations

Record-Setting Single-Wavelength Performance with China Unicom

Teamwork between YOFC and China Unicom in May 2024 set new global benchmarks for single-wavelength transmission speeds showing 1.2 Tbit/s on a 10.2km hollow-core fibre connection. The setup backed 32 wavelength channels at 1.2 Tbit/s each reaching a total transmission ability of 38.4 Tbit/s.

The test confirmed that:

  • Hollow-core fibre can keep signal quality at unmatched data speeds
  • Engineers can simplify standard dispersion correction methods
  • Experts can fine-tune signal processing algorithms for the special traits of hollow-core transmission

Ultra-High Capacity Transmission with China Telecom

In July 2024, YOFC and China Telecom showed they could send signals in real time at 100.4 Tbit/s through hollow-core fibres over 20km. This feat had an impact on optical communications reaching a capacity-distance product of 2,008 Tbit/s·km. That same month, YOFC teamed up with ZTE Corporation to display the first real-time transport of single-wavelength 1.2Tb/s. They pushed 3W (34.8dBm) of power through 20km of hollow-core fibre.

"This demonstration completed the hollow-core fibre deployment and large-capacity transmission between China Telecom's Hangzhou Intelligent Computing Center and Yiqiao IDC," noted China Telecom's Zhejiang branch. "We have always maintained the leading position in the field of basic transmission networks. This project demonstrated and verified the hollow-core fibre and 1.2Tbit/s transport system in the field network, providing detailed engineering data and demonstration applications."

The system used top-notch ZTE optical transport gear along with better spectral efficiency, optimised baud rates, and improved amplification tech. It stretched out 41 C-band 1.2Tbit/s wavelengths and 64 L-band 800Gbit/s wavelengths reaching one-way transmission capacity over 100Tbit/s.

Technical Challenges and Engineering Solutions

YOFC faced many hurdles beyond basic fibre manufacturing when trying to implement hollow-core fibre in real-world networks:

Splicing and Connection Breakthroughs

A key advancement involved creating dependable fusion splicing methods between hollow-core fibres and from hollow-core to standard solid-core fibres. YOFC's engineers utilised techniques inclduing low-power discharge splicing to stop the fragile hollow structures from collapsing and mode field matching methods to boost light coupling between different fibre types. Cutting-edge alignment procedures that achieved splice losses as low as 0.05dB between hollow-core segments and 0.25dB with 54dB return loss between hollow-core and regular solid-core single-mode fibres.

The FITEL S185PMROF 3-electrode fusion splicer solves a number of these splicing challenges.

Environmental Protection Systems

Getting the field deployment right needed strong measures to protect against the environment:

  • Special cable designs to stop water from getting in or condensing inside the hollow core
  • Pull units with swivels to cut down on wear to protective end caps during setup
  • Sideways waterproof cable closures to keep the environment out at splice points
  • Special field methods to keep things clean during setup and upkeep

Nonlinear Performance Boosts

One of the biggest pluses of hollow-core fibre is that it's almost immune to nonlinear optical effects that hold back normal fibre performance. YOFC's tests proved this feature in real-world settings:

  • A single-wavelength 1.2Tb/s signal reached 3W (34.8dBm) launch power without causing a significant non-linear penalty in the 20km hollow-core fibre system
  • Dummy light injection across the ultra-wide S+C+L 19THz band showed that the extended bandwidth didn't cause noticeable power transfer effects due to stimulated Raman scattering
  • These features allow networks to have a much simpler design while supporting higher power levels than standard fibre

How This Affects Next-Generation Networks

Hollow-core fibre technology breakthroughs come at a crucial time in global telecommunications progress, with several key areas set to gain right away:

Data Center Connections

The very low delay of hollow-core fibre (31% less than standard fibres) makes it perfect for:

  • High-speed trading where tiny time gains lead to big money advantages
  • AI/ML model training that needs lots of parallel processing with little wait time between computers
  • Data center timing that requires exact syncing and quick signal travel

Far-Off Sending

The small signal loss (0.05dB/km) and less signal distortion have a big impact on:

  • Undersea communication networks that are hitting their limits
  • Long-distance land-based main network structures
  • Networks that need fewer signal boosters and simpler signal handling

AI and Computer Systems

As China Telecom said after the field test hollow-core fibre offers "real-world uses for connecting spread-out smart computing hubs." This tech tackles the huge rise in data needs from AI apps giving:

  • Better links for cloud computing and edge apps
  • A base for future data-heavy tech
  • Less power use through simpler signal handling and fewer boost stages

Teamwork in the Industry and Plans for Sales

YOFC's tests show a big shift from lab work to being ready for market use. The company has teamed up with China's three main phone companies (China Mobile, China Unicom, and China Telecom) demonstrating broad industry interest in the technology.

What's Next in Research

YOFC's hollow-core fibre technology has made a big breakthrough, but research goes on in several key areas:

  • Extended Wavelength Bands: Right now, tests look at C and L bands, but studies show hollow-core fibre might support much wider ranges of light.
  • Further Attenuation Reduction: In theory, we could see signal loss drop below 0.01dB/km if we improve how we make these fibres.
  • Simplified Terminal Equipment: The way hollow-core fibres work could lead to much simpler signal processing in fast optical networks.
  • Alternative Core Structures: Many rival hollow-core designs prove valuable for certain uses. Research continues to fine-tune setups for different needs.
     

Wrapping Up

YOFC's hollow-core fibre demonstrations have an impact on optical communications technology. These breakthroughs in real-world network environments set new records ushering in a new age of telecommunications infrastructure.

The combination of much lower latency (31% less than regular fibres) better transmission speed (47% quicker signal movement) much less signal weakening (as low as 0.05dB/km), and few nonlinear effects makes hollow-core fibre technology key to enable next-gen applications from data centers to long-distance networks.

As YOFC keeps improving its manufacturing methods and boosting production hollow-core fibre tech looks set to become a key part of global telecom infrastructure. This addresses the constant need for quicker higher-capacity, and more responsive communications in our linked world.