The name “solar panel” may lead most people to believe that they have the totality of its functions down pat, but scientists who recently published in the journal Optics Letters will definitely beg to differ, as they just found a way to use these panels for wireless communications underwater.
This novel use of solar panels functions as a sort of play on the ordinary use of these devices, which is primarily to turn light into electrical energy for the grid. Instead, this fresh take on solar panels has these panels arranged in series to function as signal detectors; this, in turn, may provide underwater communications with a “cost-effective, low-energy” alternative, according to a press release via EurekAlert!.
“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 lead Jing Xu from Zhejiang University.
Xu and the research arranged a series of solar panels in an array to form an “optimized lens-free system” for optical detection—a system that appears to also function underwater. This, they say, is due to the fact that these solar panels possess a much larger detection area compared to what’s normally employed in wireless communications, such as photodiodes.
The team arranged a series of solar cells in a 3 × 3 array, giving the device a total detection area of around 12 cm2 (1.8 in2). The device was then tested under a water tank measuring 7 m (23 ft) long; from there, the team placed mirrors underwater to recreate an effective transmission distance of 35 m (114.8 ft).
Testing using this setup revealed that the device was reliable and stable, and consumed little power despite its good performance. Its effective 20-dB bandwidth also increased with array size, reaching up to 24.2 MHz at a 3 × 3 array. This increased bandwidth, the researchers claim, lead to a higher data rate, which was subsequently boosted by applying a reverse bias voltage of 90 V. By using what’s known as amplitude-shift keying modulation, the novel underwater setup enabled and managed an underwater optical link at 35 m with data rates of up to 150 Mbps.
Xu continued: “Because solar cells are [mass-produced], the proposed scheme is quite [cost effective]. 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.”
Xu added: “This type of system could even allow data exchange and power generation with one device,” noting that their unique alternative could help future technologies skip the need for direct cabling to underwater devices that are in need of both power and communication, like remote-controlled submersibles and diving equipment.
References
- Coxworth, B. (2022, February 16). Solar cells used to boost wireless underwater communications. New Atlas. https://newatlas.com/science/solar-cells-wireless-underwater-communications/
- OPTICA. (2022, February 16). Researchers use solar cells to achieve fast underwater wireless communication. EurekAlert! https://www.eurekalert.org/news-releases/943699
- Tong, Z., Tong, Z., Yang, X., Yang, X., Zhang, H., Zhang, H., Dai, Y., Dai, Y., Chen, X., Chen, X., Xu, J., Xu, J., & Xu, J. (2022). Series-connected solar array for high-speed underwater wireless optical links. Optics Letters, 47(5), 1013–1016. https://doi.org/10.1364/OL.449466
