Hengtong wins top CSIST award for deep-sea optical cable work

Hengtong won the 2025 Chinese Society of Imaging Science and Technology Grand Prize for Scientific and Technological Progress for a marine optical fiber and cable project built with university partners. The award recognizes advances in submarine transmission capacity, pressure resistance and industrialization across a 22,000-kilometer cable portfolio.

Why it matters: - Submarine optical cables carry more than 95% of global international data traffic, making deep-sea cable performance critical to the digital economy and strategic communications. - The CSIST Grand Prize signals national-level recognition for Hengtong’s marine optical communications work and its move from lab research to large-scale deployment. - The award also underscores China’s push for more self-sufficient supply chains in core materials, fibers and submarine cable systems.

What happened: - The 2025 Chinese Society of Imaging Science and Technology Science and Technology Awards named Hengtong’s marine optical fiber and cable project as a Grand Prize winner for Scientific and Technological Progress. - The project was completed by Hengtong Huahai, Hengtong Fiber and Hengxin Quartz, together with Soochow University and Xi'an Jiaotong-Liverpool University. - The recognized project is called "Key Technologies and Applications of Space-Division Multiplexing-Based Marine Optical Fibers and Cables." - The award was announced in 2026, according to the release.

The details: - Hengtong said the project addressed core deep-sea transmission challenges, including ultra-large-capacity communication, transmission stability, 10,000-meter-class hydrostatic pressure, and water and gas tightness. - The project team said it achieved self-sufficiency across the industrial chain, from core materials and key products to complete equipment. - Hengtong developed an algorithm to reduce inter-core crosstalk in space-division multiplexing systems and to support long-haul submarine transmission. - The company said the algorithm lowers computational complexity while preserving independent transmission across optical field lines in different cores. - Hengtong independently developed ultra-low-loss single-core and multi-core weakly coupled marine fiber profile structures. - The team used precise material formulations and highly uniform deposition control to reduce fiber attenuation to near the theoretical limit of silica substrate. - The team also built a fiber life prediction model to control attenuation deviations in 32 fiber pair cables. - Hengtong designed a deep-sea cable structure, developed specialized welding equipment and optimized manufacturing processes to withstand 10,000-meter-class pressure and improve water and gas tightness. - The submarine cables passed pressure and water penetration tests and showed improved water-blocking performance. - Hengtong said the technologies have already been applied in the world’s first 16 fiber pair submarine cable system based on space division multiplexing. - The technologies were also used in the fully self-owned 22,000-kilometer PEACE intercontinental submarine cable linking Asia, Africa and Europe. - Those deployments helped Hengtong Huahai reach No. 1 market share in China and rank among the global top four in submarine cable systems.

Between the lines: - The award suggests Hengtong is trying to move deeper into high-end subsea infrastructure, where technical barriers and reliability requirements are high. - The project’s focus on both performance and manufacturing suggests the competitive edge is not only in design, but also in scalable production. - The emphasis on full-chain control points to a broader industrial strategy around domestic capability in critical communications infrastructure.

What's next: - Hengtong said it will keep building on its integrated "quartz materials + specialty optical fibers + submarine cables" business chain. - The company plans to deepen industry-university-research collaboration and continue developing marine communication technology. - Hengtong said it aims to support China’s marine information infrastructure and the digital economy.

The bottom line: - Hengtong’s award highlights a push to pair deep-sea cable engineering with domestic manufacturing depth, as demand rises for faster and more resilient international data links.