(MIT: Cambridge, MA) -- MIT researchers have demonstrated the first system for ultralow-power underwater networking and communication that can transmit signals across kilometer-scale distances.

This technique, which the researchers began developing several years ago, uses about one-millionth the power that existing underwater communication methods use. By expanding their battery-free system’s communication range, the researchers have made the technology more feasible for applications such as aquaculture, coastal hurricane prediction, and climate change modeling.

“What started as a very exciting intellectual idea a few years ago—underwater communication with a million times lower power—is now practical and realistic,” says Fadel Adib, associate professor in the Department of Electrical Engineering and Computer Science and director of the Signal Kinetics group in the MIT Media Lab. “There are still a few interesting technical challenges to address, but there is a clear path from where we are now to deployment.” 

Underwater backscatter enables low-power communication by encoding data in sound waves that it reflects, or scatters, back toward a receiver. These innovations enable reflected signals to be more precisely directed at their source.

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