Researchers showed that high data rates can be achieved by using an array of solar cells as the detector in an underwater wireless optical communication system.
CREDIT: Jing Xu, Zhejiang University
Optimized approach simplifies underwater optical data links; could enable devices that transmit data and produce power
Although solar cells are typically designed to turn light into power, researchers have shown that they can also be used to achieve underwater wireless optical communication with high data rates. The new approach—which used an array of series-connected solar cells as detectors—could offer a cost-effective, low-energy way to transmit data underwater.
“There is a critical need for efficient underwater communication to meet the increasing demands of underwater data exchange in worldwide ocean protection activities,” said research team leader Jing Xu from Zhejiang University in China. For example, in coral reef conservation efforts, data links are necessary to transmit data from divers, manned submarines, underwater sensors and unmanned autonomous underwater vehicles to surface ships supporting their work.
In the Optica Publishing Group journal Optics Letters, Xu and colleagues report on laboratory experiments in which they used an array of commercially available solar cells to create an optimized lens-free system for high-speed optical detection underwater. Solar cells offer a much larger detection area than the photodiodes traditionally used as detectors in wireless optical communication.
“To the best of our knowledge, we demonstrated the highest bandwidth ever achieved for a commercial silicon solar panel-based optical communication system with a large detection area,” said Xu. “This type of system could even allow data exchange and power generation with one device.”
Optimizing solar cells for communication
Compared to using radio or acoustic waves, light-based underwater wireless communication exhibits higher speed, lower latency and requires less power. However, most long-distance high-speed optical systems are not practical for underwater implementation because they require strict alignment between the transmitter emitting the light and the receiver that detects the incoming light signal.
Because solar cells detect light from a large area and convert it to an electrical signal, using them as detectors can ease the transmitter-receiver alignment requirement in an underwater wireless communication system. However, it has been difficult to achieve high bandwidth because solar cells are optimized for energy harvesting rather than communication.
“Until now, achieving high-speed links using off-the-shelf silicon solar cells has required complex modulation schemes and algorithms, which need intense computing resources that use extra power and create a high processing latency,” said Xu. “Using modeling and simulation of connected solar cells, we optimized the peripheral circuit, which significantly improved the performance of our solar cell-based detector.”
The researchers tested the new design, which used a 3×3 solar array to create a detection area of 3.4 × 3.4 centimeters, in a 7-meter-long water tank that emulated an underwater channel. Mirrors were used to extend the pathlength of the optical signal, creating a transmission distance of 35 meters. The system showed reliable stability, low power consumption and high performance. As the size of the solar array increases from 1×1 to 3×3, the ?20-dB bandwidth increases from 4.4 MHz to 24.2 MHz.
Even though a simple modulation scheme was used, the new system exhibited a much higher detection bandwidth — which leads to a higher data rate — than has been reported in other studies using commercial silicon solar cells with a large detection area as detectors. Applying a reverse bias voltage of 90 V boosted the bandwidth further, allowing them to achieve a ?20-dB bandwidth of 63.4 MHz. This bandwidth enabled a 35-m/150-Mbps underwater wireless optical link using the simplest form of amplitude-shift keying modulation.
“Because solar cells are mass produced, the proposed scheme is quite cost effective,” said Xu. “Beyond the underwater world, this type of detector could also be used in visible light communication, a type of wireless communication that uses visible light from LEDs and other sources to transmit data across distances.”
To optimize the system for real-world applications in underwater communication, the researchers plan to next study its performance with weak optical signals. This will show how well it works in muddy water and with movement. They are also working to make the system more practical by fine tuning key parameters like the number of solar cells in the array and the required reverse bias voltage.
More from: Zhejiang University
The Latest Updates from Bing News & Google News
Go deeper with Bing News on:
Underwater optical data links
- No sea serpents, mobsters but Tahoe trash divers strike gold
In addition to removing 25,000 pounds (11,339 kilograms) of underwater litter since last May, divers and volunteers have been meticulously sorting and logging the types and GPS locations of the waste.
- US Navy to Deploy Submarine-Launched Drones
“Blackwing employs an advanced, miniature electro-optical and infrared (EO/IR) payload, Selective Availability Anti-spoofing Module (SASSM) GPS and AeroVironment’s secure Digital Data Link ...
- Underwater volcano in Antarctica triggers 85,000 earthquakes
A long-dormant underwater volcano near Antarctica has woken ... So the researchers used data from those seismic stations, as well as data from two ground stations for the global satellite ...
- Olympus Tough TG-1 iHS packs 12-megapixel sensor, f/2.0 lens, ruggedized housing for $399
A shutter range from bulb to 1/2000 second boosts versatility, while tools like GPS, an e-compass and pressure-measuring manometer combine to provide data-rich pictures while also aiding in-camera ...
- Twitching Fish Plays Pokemon Underwater
Check out the link above to stream the video. There is even a chat bar on the side, which allows anyone to jump into the fishy conversation. If the fish looks dead though, it’s probably just ...
Go deeper with Google Headlines on:
Underwater optical data links
Go deeper with Bing News on:
Underwater wireless optical communication
- Optical Communication and Networking Equipment is anticipated to reach US$ 44.5 Billion in 2032 – Persistence Market Research
New York, May 12, 2022 (GLOBE NEWSWIRE) -- As per a study by Persistence Market Research, from US$ 22 Billion in 2022 to US$ 44.5 Billion in 2032, the global optical communication and networking ...
- Professors by Expertise
Aghdam Wireless mobile sensor networks; Underwater sensor networks ... Object detection and target tracking, Communication, VLSI signal processing. Dr. Otmane Ait-Mohamed Hardware Verification, Formal ...
- The Best Midrange Point-and-Shoot Digital Cameras for Artists
This 12-megapixel compact camera has a 4x optical zoom (25-100mm equivalent) lens with a fast f/2.0 aperture that will help you shoot low-light shots underwater without having to use the flash. For ...
- Underwater Wireless Communication (UWC) Market See Huge Growth for New Normal | SAAB AB, Fugro, Konsberg Gruppen
A2Z Market Research published new research on Global Underwater Wireless Communication (UWC) covering micro level of analysis by competitors and key business segments (2022-2029). The Global ...
- Latest on R&D on Wired Transmission Technologies
On the contribution side, broadcasters are now starting to use optical fiber and the ... 4.2 Using Wired IP Technology for Wireless IP Transmission Underwater The STRL has made progress in R ...