Revolutionary Underwater Communication: MIT Showcases Milestone in Low-Power, Long-Distance Subaqueous Communication

MIT has recently disclosed a game-changing underwater communication system that requires remarkably low power to transmit signals across distances of several kilometers. Utilizing the principles of underwater backscatter and avant-garde design, the technology offers promising applications in sectors such as aquaculture, climate data analysis, and forecasting of hurricanes.

The technology promises battery-free communication underwater over spans of several kilometers, making it beneficial for monitoring climate variations and shifts in coastal conditions.

Researchers at MIT have successfully developed the inaugural system for ultra-low-energy underwater networking, capable of transmitting signals across distances on the order of kilometers.

Several years in the making, the method employs power levels that are a mere millionth of what current underwater communication systems require. Through expanding their system’s communication capabilities, the research team has rendered the technology more applicable for areas including aquaculture, climate modeling, and prediction of coastal hurricanes.

Associate Professor Fadel Adib, of the Department of Electrical Engineering and Computer Science and head of the Signal Kinetics group in the MIT Media Lab, remarks that what was once an intriguing theoretical concept of achieving underwater communication with substantially lower energy consumption is now practical and attainable. While some technical challenges remain, the path toward operational deployment is clear.

The communication device comprises an array of piezoelectric transducers that facilitate battery-free underwater communication.

The Role of Underwater Backscatter

Underwater backscatter allows for low-energy data transmission by modulating data in sound waves, which are then reflected back towards a receiving unit. These advances facilitate the precise directing of reflected signals back to their origin.

This feature, termed “retrodirectivity,” results in fewer signals scattering off course, thereby enhancing the efficiency and range of communication.

Tests conducted in both riverine and oceanic environments revealed that the retrodirective device achieved a range over 15 times greater than existing devices. Nonetheless, the studies were constrained by the physical limitations of the docks accessible for testing.

The team also formulated an analytical model to ascertain the maximum achievable range of this backscatter technology, substantiating it through experimental data.

Scholarly Contributions and Authorship

Findings from this research will be presented in two forthcoming papers at the ACM SIGCOMM and MobiCom conferences. The research team includes co-lead authors Aline Eid, formerly a postdoc and now an assistant professor at the University of Michigan, and Jack Rademacher, a research assistant, as well as other research assistants and postdocs.

Mechanism of Sound Wave-Based Communication

The devices utilize an array of nodes composed of piezoelectric materials that capture and reflect sound waves. Upon impact, these materials convert mechanical energy to electrical charges, which are then used to reflect some of the acoustic energy back to its source.

However, the inherent challenge lies in the dispersion of the backscattered signals, as only a minor fraction ultimately reaches the source. The researchers overcame this limitation by employing a Van Atta array—a radio device with symmetrically paired antennas designed to reflect energy back to its source.

Further Trials and Future Development

The team conducted over 1,500 tests in the Charles River and the Atlantic Ocean. Their device achieved a range of 300 meters, more than a 15-fold increase over previous demonstrations. They were, however, restricted by the size of the available docks for testing.

Subsequently, the team crafted an analytical model to outline the communication limits of this novel technology. By inputting variables such as input power and node dimensions, users can ascertain the device’s expected range. The model’s accuracy was verified through experimental data, revealing it could reliably predict the range of acoustic signals.

Going forward, the team aims to continue their research and explore the commercial viability of this technology, while also making tools and data available for further academic study.

External Evaluations

Omid Abari, an assistant professor of computer science at the University of California, Los Angeles, who was not part of this study, lauded the significant advancements in the realm of underwater communication. The paper, he noted, was groundbreaking in incorporating the Van Atta Reflector array technique into underwater settings, substantially amplifying the communication range and bringing battery-free underwater communication closer to real-world applications.

Funding and Support

This research has been partly funded by various organizations, including the Office of Naval Research, the Sloan Research Fellowship, the National Science Foundation, the MIT Media Lab, and the Doherty Chair in Ocean Utilization.

Frequently Asked Questions (FAQs) about Underwater Communication Technology

More about Underwater Communication Technology

• MIT’s Official Announcement on Underwater Communication Technology
• ACM SIGCOMM Conference Papers
• MobiCom Conference Papers
• Woods Hole Oceanographic Institution Collaboration
• Office of Naval Research Funding Information
• Sloan Research Fellowship
• National Science Foundation Grants
• MIT Media Lab Research Groups
• Doherty Chair in Ocean Utilization