SWT PhotonLink Optical Communication Modem is a wide angle, easy alignment subsea optical communication system designed for high speed wireless data transfer, low latency two way communication, and reliable operation in high ambient light underwater environments.


Underwater communication has always been one of the key challenges in subsea operations. Acoustic communication can provide long-range connectivity, but it is often limited by low bandwidth and higher latency. Tethered communication offers stable high-speed data transfer, but cables can restrict vehicle movement, increase deployment complexity, and create additional operational risks.
As AUVs, ROVs, seabed observatories, and subsea sensor networks become more widely used, there is a growing need for a faster, lower-latency, and easier-to-deploy wireless communication solution underwater.
AquaLink UWOC Modem is designed to meet this demand. Based on underwater wireless optical communication technology, AquaLink provides a high-speed, real-time, bidirectional data link for subsea equipment. It is suitable for applications such as underwater data recovery, wireless telemetry, ROV/AUV communication, and subsea sensor connectivity.
Compared with acoustic communication, underwater optical communication offers significantly higher bandwidth and lower latency. However, traditional optical communication systems often require accurate alignment between transmitter and receiver.
AquaLink is designed with a wide-angle optical transmission structure, with a beam angle of ≥ 60°. This helps reduce alignment difficulty during underwater operations and makes it easier to establish and maintain a stable optical link between subsea devices.
For mobile platforms such as ROVs and AUVs, as well as semi-fixed subsea instruments, this wide-angle design can improve operational flexibility and reduce the need for precise positioning.
AquaLink supports a net data rate of ≥ 40 Mbps, enabling fast transfer of sensor data, image data, mission logs, and other large data sets. In short- to medium-range subsea communication scenarios, optical communication can greatly improve data recovery efficiency compared with conventional low-bandwidth acoustic systems.
For example, after an AUV completes a survey mission, AquaLink can be used to establish a wireless optical link with a subsea station or ROV, allowing high-speed data transfer without fully recovering the vehicle.
AquaLink supports real-time duplex transmission, with one-way transmission available as an optional configuration. This allows the system to support both high-speed data download and two-way communication for control commands, status feedback, and system monitoring.
This capability is useful for ROV/AUV operations, subsea equipment testing, seabed sensor networks, and underwater telemetry applications where low-latency two-way data exchange is required.
AquaLink is equipped with a Gigabit Ethernet interface, while remaining compatible with 100 Mbps and 10 Mbps Ethernet connections. This makes it easier to integrate with existing subsea platforms, control systems, data acquisition units, and onboard electronics.
The use of a standard Ethernet interface helps reduce integration complexity and allows AquaLink to connect with ROVs, AUVs, sensor modules, data loggers, and topside control systems.
AquaLink features a compact cylindrical design, with a main body dimension of approximately Ø130 mm × 300 mm. It is suitable for installation on a wide range of underwater platforms.
The system operates with DC 24 V power supply, with other voltage options available. Its single-end power consumption is < 30 W, helping reduce the overall power demand of subsea systems, especially for battery-powered platforms such as AUVs and long-term underwater observatories.
The standard configuration supports operation at depths of up to 1,000 m, with deeper water configurations available as optional versions. The system also uses a 13-pin underwater connector for subsea integration.
• Wide-angle optical transmission ≥ 60°
• Net data rate ≥ 40 Mbps
• Communication range ≥ 15 m
• Real-time duplex transmission
• Gigabit Ethernet interface
• Up to 1,000 m depth operation
• Compact low-power design
• 13-pin underwater connector
AUV Data Recovery
AquaLink can be used for high-speed wireless data download after AUV missions, reducing the need for frequent vehicle recovery.
ROV Communication and Control
The modem can support short-range high-speed data exchange, auxiliary communication, and local wireless control during ROV operations.
Seafloor Sensor Networks
For seabed sensors, underwater observatories, and data logging systems, AquaLink provides a practical method for fast wireless data retrieval.
Subsea Equipment Telemetry
During underwater testing, commissioning, and engineering operations, AquaLink can be used for real-time status monitoring, parameter transmission, and data feedback.
The future of subsea operations is moving toward greater autonomy, higher data volume, and more flexible underwater networking. High-speed, low-latency wireless communication will become an important enabling technology for next-generation underwater systems.
With its wide-angle optical design, high-speed data rate, real-time duplex communication, and standard Ethernet interface, AquaLink UWOC Modem provides a practical and flexible solution for cable-free subsea connectivity.
AquaLink UWOC Modem — high-speed wireless optical communication for subsea applications.
