Underwater Wi-Fi or No Longer A Dream: Aqua-Fi Completes Small Range Experiments

According tomedia reports, radio waves cannot travel in the water, making it difficult for divers or submersibles to transmit information wirelessly to the surface. But scientists are trying to change that by developing an underwater version of Wi-Fi. Back in 2018, researchers at Saudi Arabia’s King Abdullah University of Science and Technology (KAUST) conducted a study on how to use lasers to transmit high-definition video underwater.

Underwater Wi-Fi or No Longer A Dream: Aqua-Fi Completes Small Range Experiments

Aqua-Fi, the latest experimental new system, is built on this technology.

Users, such as a diver wearing a respirator, first send data from a smartphone placed in a waterproof shell. The data was initially transmitted as radio waves to a small device installed on the diver’s tank a few feet away.

The microcomputer in the device then converts the data into a series of ultra-high-speed light pulses, each displayed in binary code. These pulses are then emitted to the surface of the water, where either a 520nm integrated laser is used or a set of green LEDs can be sent to a relatively short distance with little energy, while the laser can send data to a greater distance but require more energy.

Upon reaching the surface of the water, the photodetector at the bottom of the ship receives a light pulse and then converts it back to the original photo or video from the computer connected together. There, the documents can be uploaded via satellite to the Internet.

To date, the Aqua-Fi system has been used to upload and download multimedia in two stationary waters several meters apart. But before it can be put into practical use, researchers must also adjust it to meet challenges such as the light scattering effect of fast-moving water — a spherical receiver that can be used to detect light pulses from all directions.

“We’ve created a relatively inexpensive and flexible way to connect the underwater environment to the global internet,” said Associate Professor Basem Shihada, lead scientist of the study. “