Aquatic internet, which sends data through light beams, could allow divers to transmit footage from under the sea to the surface immediately.
The internet is an indispensable communication tool that connects tens of billions of devices worldwide and yet we struggle from underwater to connect to the web. “People from both academia and industry want to monitor and explore underwater environments in detail,” states the first speaker, Basem Shihada. Under the sea, wireless internet would allow divers to talk without hand signals, and send live data to the surface.
Communication with electronic, auditory, and visible light transmissions is possible underwater. However, radio can only carry data over short distances, while long distances are supported by acoustic signals but with very limited data rate. Visible light will fly far and hold loads of data, but a direct line of sight between transmitters and receivers is needed for the narrow light beams.
Now, Shihada’s team has built an Aqua-Fi, an underwater wireless system that supports internet services like sending multimedia messages using either LEDs or lasers. LEDs provide a low-energy communication option for short-distance communication, while lasers can still carry data but need more power.
The Aqua-Fi system used green LEDs or a 520-nanometer laser to transmit the data to a light detector attached to another device from a tiny, basic machine. The first machine translates photos and videos into a series of 1s and 0s, converted into light beams which switch on and off at very high speeds. The light detector detects this variability and transforms it back into 1s and 0s which are transformed back into the initial footage by the receiving machine. The researchers tested the device by concurrently importing and storing multimedia in stagnant water from two machines placed apart a few metres.
For a round trip, they recorded a maximum data transfer speed of 2.11 megabytes per second and a mean delay of 1.00 milliseconds. “This is the first time anyone has used the internet underwater completely wirelessly,” says Shihada.
In the real world, Aqua-Fi would send data from a diver ‘s smartphone to a “gateway” device attached to its gear using radio waves. Instead, like a booster that stretches a household internet router’s WiFi coverage, this gateway transfers the data to a surface-connected device with a light beam with satellite.
Aqua-Fi will not be available until several obstacles are surmounted by researchers. “We hope to improve the link quality and the transmission range with faster electronic components,” explains Shihada.
The light beam in moving waters must also remain perfectly aligned with the receiver, and the team is considering a spherical receiver which can capture light from all angles.
“We have created a relatively cheap and flexible way to connect underwater environments to the global internet,” says Shihada. “We hope that one day, Aqua-Fi will be as widely used underwater as WiFi is above water.”
