TARF doesn't require a perfectly still sea, either. New signal processing algorithms use the frequency of waves to tell the difference between large waves and the tiny ones scientists are looking for. The initial approach only works in waves nearly 6.3 inches high, but MIT hoped to refine it for use in rough ocean waters.

The system isn't about to transmit photos or highly detailed reports when the current prototype can only transmit data at a few hundred bits per second. Decades-old dial-up modems are faster. And of course, it's focused on one-way transmissions. Even that little bit of data might be enough for all kinds of applications, though. Submarines could send their findings directly to aircraft (including drones) circling above while remaining safely underwater, and without using boats as intermediaries. That could keep sailors out of harm's way, and make transmissions possible in situations where conventional ships just aren't available.