Revolution in Fiber Optics from China: 1,3 Tb/s Speed Achieved on a Single Channel

While the capacity race in next-generation communication technologies continues unabated, a China-based consortium has achieved a significant milestone in the field of fiber optic transmission. In a project jointly conducted by China Telecom, Yangtze Optical Fibre and Cable Joint Stock Limited Company, and Dekoli, a field test under real-world conditions was successfully completed using hollow-core fiber optic cables. Emerging from the laboratory environment and implemented in a commercial field, this test achieved a data transmission speed of 1,2 Tb/s per wavelength, recording a global first. The system reached a tremendous total capacity value of 51,3 Tb/s over a route approximately 206 kilometers (128 miles) long. These figures paint a highly promising picture for the future of backbone networks in today's world, where global data demand is increasing exponentially.

The fundamental difference between hollow-core fiber technology and traditional fiber cables lies in the transmission method of light. While standard fiber optic cables transmit data as light pulses through a solid glass core, this next-generation technology guides light through air (or a vacuum). The propagation of light through air significantly reduces signal latency while substantially increasing the amount of data and capacity transmitted simultaneously. This structural advantage is generating great excitement because it holds the potential to overcome the physical limitations faced by existing traditional fiber cables. It is expected that especially massive-scale data centers, cloud computing infrastructures, and international backbone networks will become much more efficient with this technology.

The achievement of the system's massive capacity of 51,3 Tb/s is directly related not only to the type of cable used in the infrastructure but also to the intelligent software and transmission algorithms developed. The research team has integrated an adaptive speed control mechanism for each wavelength to maximize transmission performance. By performing flexible power distribution across the channel, this system optimizes data based on dynamic conditions rather than static rules. The way each wavelength carries data, channel spacing, and power levels can be adjusted in real-time. Thus, rather than treating the entire channel spectrum as a single fixed value, hybrid transmission is achieved by managing the performance of each channel in a coordinated and balanced manner.

One of the biggest technical challenges encountered in high-capacity data transmission is the signal loss over long distances and the stability issues experienced during high-power transmission. By solving this historical problem created by high-power signal transmission in real-world network conditions, the project team has achieved an unprecedented success. In this context, a brand-new high-power amplification design has been developed, based on a cascaded dual-gain unit architecture and a multi-element doping approach. Thanks to these next-generation amplifiers, maximum output powers reaching up to 33,5 dBm were attained, and optical signal instability was prevented. This innovative architecture has succeeded in maintaining signal performance at a consistent level by providing a strong gain flatness across the entire operating range.

In optical networks where such high power levels are utilized, safety and equipment protection mechanisms are just as critical as speed. To minimize the risks that potential optical connection failures could create, engineers have taken various precautions by weaving a multi-layered security net into the system. In this context, a special detection system that continuously monitors signal stability and can detect power anomalies in the optical path within seconds has been integrated into the system. When any unsecured or abnormal condition is detected, locked shutdown functions that automatically stop the system are activated, and alarm signals are sent across the general network. The test findings, also published by TrendForce, have clearly proven that hollow-core fiber technology works extremely stably and reliably even under commercial conditions outside the laboratory, establishing a new benchmark in the industry.