ZTE assists China Telecom in launching the world's first live single-wavelength 1.2Tbit/s hollow-core fiber transmission system with unidirectional capacity over 100Tbit/s

• The system extends 41 C-band 1.2Tbit/s wavelengths and 64 L-band 800Gbit/s wavelengths
• It achieves a unidirectional transport capacity of over 100Tbit/s in the field network and a transmission distance of 20km in the field network

Shenzhen, China, 29 July 2024 - ZTE Corporation (0763.HK / 000063.SZ), a global leading provider of integrated information and communication technology solutions, together with Yangtze Optical Fibre and Cable Joint Stock Limited Company (YOFC) and Huaxin Design Institute, has assisted China Telecom in releasing the world's first demonstration project of a hollow-core fiber transmission system with single-wavelength 1.2Tbit/s, unidirectional beyond-100Tbit/s, and a transmission distance of 20km in the live network at the "All-Optical Network Technology and Application in the Intelligent Computing Era" seminar of the CCSA TC618/NGOF. This marks an important step forward in exploring cutting-edge optical communication technologies and building communication infrastructure oriented to intelligent computing scenarios.  

Relying on the national key R&D project "Ultra-Broadband Optical Transmission System and Application Demonstration Based on New Fibers", this demonstration completed the hollow-core fiber deployment and large-capacity transmission between China Telecom's Hangzhou Intelligent Computing Center and Yiqiao IDC. As a key node of China Telecom's intelligent computing power layout "2+3+7+M", the Hangzhou Intelligent Computing Center has been deployed with the 1k GPUs computing power of the China Telecom Cloud.

To meet the requirements for distributed computing power with large bandwidth and low latency of optical networks, ZTE introduces its advanced high-speed optical transport equipment. Combined with improvements in spectral efficiency, baud rate optimization, and amplification optimization technologies, the system extends 41 C-band 1.2Tbit/s wavelengths and 64 L-band 800Gbit/s wavelengths. It achieves a unidirectional transmission capacity of over 100Tbit/s and a transmission distance of 20km in the field network.  

The hollow-core fiber cable, independently developed by YOFC, is deployed in the field network with multiple waterproofing solutions. For instance, water-blocking glue and double-layer plastic caps are used at the cable ends to isolate the atmosphere, a pulling unit with a swivel is employed for cable deployment to minimize wear on the end caps, and a horizontal waterproof cable closure is utilized at the fusion splice point. Additionally, breakthroughs in hollow-core fiber fusion splicing technologies, such as low-power discharge and mode field matching, have achieved 0.05dB fusion splice loss between hollow-core fibers and 0.25dB fusion splice loss with 54dB return loss between hollow-core fibers and standard solid-core single-mode fibers.

China Telecom's Zhejiang branch said: "We have always maintained the leading position in the field of basic transmission networks. By undertaking the national key R&D project, we have demonstrated and verified the hollow-core fiber and 1.2Tbit/s transport system in the field network, and can offer detailed engineering data and demonstration applications. In the future, we will further cooperate with the industry to conduct research on a larger scope, and provide practical scenarios for the interconnection of distributed intelligent computing centers."

Moving forward, China Telecom will continue to expand the hollow-core optical cable environment and build a platform for testing and verifying new technologies and applications oriented towards intelligent computing scenarios. This effort aims to continuously promote technological innovation and application expansion in the communication industry.