Liutong Photonics SC-DAS-1550-FA Integrated Sensing and Communications Device Monitors Typhoon Hagiwara via Submarine Cable

Starting September 23, super typhoon "Hagupit" struck Guangdong head-on. Areas along the typhoon's path saw gusts of up to force 16 to 17, making it the world's strongest storm so far this year. Eleven cities in Guangdong announced "five suspensions" (classes, work, production, transport and business).

Lingdingyang, spanning the Greater Bay Area, was the first stop hit directly by "Hagupit." It is critically important to dynamically track the real-time status of offshore engineering equipment during a typhoon and to accurately collect, in real time, wave height and ocean current speed and direction, laying a scientific foundation for long-term disaster prevention and mitigation in the marine economy.

The integrated sensing-communications equipment from Liutong Photonics, an incubated company of the Hangzhou Institute of Optics and Mechanics, turns conventional communications fiber into a "stethoscope." Combined with an AI "brain," it converts undersea communications cables into a distributed acoustic sensor array. The sensing equipment captures faint vibration signals generated on the seabed by waves, ocean currents and storm surges. These vibration signals are collected in real time by the highly sensitive integrated sensing-communications equipment and transmitted back to land-based monitoring stations. For this typhoon monitoring deployment, our SC-DAS-1550-FA equipment was used, with a sensing range >=50km, spatial resolution <=2m, noise floor <=2dB 𝑝𝜀/sqrt(𝐻z) @100𝐻𝑧, and a frequency range of 1mHz~10KHz.

Schematic of Liutong Photonics' ocean monitoring during the typhoon

Liutong Photonics also developed an ocean physics model for its integrated sensing-communications equipment, tightly coupling it with deep-learning AI algorithms. This "AI brain" can extract, in real time and with high accuracy, ocean current speed and direction, shallow-water depth changes, wave height, wave period and wave direction from massive volumes of vibration data. The system provides a very wide sensing range and high spatial resolution, enabling continuous, real-time monitoring of large sea areas.

Wave information monitoring during the typhoon

During the typhoon monitoring, Lutong Photonics used the submarine communication cable of the Guishan offshore wind farm to monitor in real time the impact, vibration and deformation of turbine foundations, tower sections and submarine cables caused by ocean waves and currents. By analyzing data on turbine impacts before, during and after the typhoon, the system can be used to detect potential structural damage and support intelligent preventive maintenance.

Monitoring of offshore wind turbines during the typhoon

Typhoon monitoring based on integrated sensing-communication equipment and an analysis system offers the following advantages: 

In-situ typhoon monitoring: The submarine communication cable lies on the seabed and can monitor the entire passage of a typhoon in situ, without being damaged by the storm overhead.

Real-time data backhaul: The submarine communication fiber runs from the seabed to land, enabling real-time transmission and processing of massive in-situ data and providing real-time data support for typhoon characterization.

Safety: In a super typhoon or other natural disaster, conventional monitoring methods may fail. Submarine communication cables are not damaged by typhoons, ensuring stable and continuous data collection.

Full-Process Tracking: From a typhoon's formation and development to landfall and dissipation, the integrated communication and sensing system can collect in-situ data while continuously transmitting the massive in-situ data back to an onshore analysis center, enabling a more comprehensive understanding of the typhoon's characteristics and its impact on the marine environment.

Company Profile

Hangzhou Liutong Photonics Technology Co., Ltd.

Founded in late 2024 and incubated by the Hangzhou Institute of Optics and Mechanics, Hangzhou Liutong Photonics focuses on developing products for space-division multiplexing optical communications and optical interconnect technology. Drawing on the founding team's years of experience, the company has quickly launched a range of space-division multiplexing optical communication products, including multicore optical amplifiers for space-division multiplexing, mode multiplexers/demultiplexers, and multicore fan-in/fan-out devices. These products have been validated and applied in fields including submarine optical cables.