Researchers have developed an improved method of streaming high-quality underwater video images using wireless technologies.
The new method, developed by the researchers at King Abdullah University of Science and Technology, is more cost-effective and flexible, and it can yield better video quality by improving the bandwidth to stream real-time underwater video images.
PhD student Abdullah Al-Halafi, together with his supervisor Basem Shihada and colleagues, achieved this by using underwater wireless optical communication (UWOC) systems. The team first constructed the real-time video transmission system, then integrated it into an UWOC setup. This configuration consumed significantly less power than existing technologies, and still offered the high bandwidths needed to stream live video.
A paper on this new development was recently published in the Journal of Optical Communications and Networking.
“Although the design and development of the system were very challenging, its ability to be programmed enabled us to reconfigure the system into several different arrangements," said Al-Halafi.
According to a news release issued by the university, the team then improved the accuracy of the detected signal by using quadrature amplitude modulation to increase the representation of information carried by the signal for a given bandwidth. They then compared it with phase-shift keying, which changes the phase of the carrier signal, while optimising the transmission for each configuration.
To test the new system, the team developed an algorithm to measure the errors that took place during the transmission (the bit error rate). They also transmitted the signal through a five-metre trough containing water of different turbidity, to gauge the quality of the video in different water types.
"Our system produced the highest-quality video streaming so far achieved in UWOC systems and provides a reconfigurable and cost-effective communications system for underwater live video streaming. It could lead to advances in underwater research and the discovery of new resources,” Al-Halafi concluded.