Researchers have created a novel form of visible light communication (VLC) technology that enables data transmission through the usage of standard lighting fixtures found in homes and businesses. One day, the technology may replace Wi-Fi as the preferred method of wireless communication.
Light-fidelity (Li-Fi) technology employs light sources and has the potential to transport data at speeds over 100 times faster than wireless-fidelity (Wi-Fi) technology, which uses electromagnetic radio waves. Li-Fi is a completely networked system that can use ultraviolet or infrared light; on the other hand, VLC is unidirectional and only uses visible light. Additionally, according to the Institute of Physics, some scientists claim that Li-Fi is the combination of Wi-Fi and VLC.
VLC is not commonly utilized since it cannot be used outside, requires a straight line of sight with a receiver, and the light source would need to be on all the time. Because of the interference, deploying a VLC system with generic white light significantly decreases data transmission accuracy and stability.
However, by developing a tri-color VLC system using red, blue, and green light projected from an organic light-emitting diode (OLED) array, researchers have now replicated white light and minimized interference in the process. As a receiver, they also set up an organic photodiode (OPD) array. In a report that was published in the journal Advanced Materials on October 19, 2023, they detailed their work.
“Our light source, which blends three wavelengths, circumvents interference thereby enhancing stability and accuracy in data transmission,” said Dae Sung Chung, a chemical engineering professor at Pohang University of Science and Technology in South Korea, in a statement. “We foresee this technology as a potentially beneficial tool for diverse industries, serving as a next-generation wireless communication solution that utilizes conventional lighting systems.”
OLEDs, which are frequently found in the display panels of many contemporary TVs, cellphones, and laptops, produce light by means of an organic layer. OLEDs feature a lighter design, are more affordable, and are more environmentally friendly than LEDs. Additionally, because OLEDs offer higher sensitivity at particular wavelengths, they are better suitable for installation in receivers.
Using the organic semiconductor element to absorb light and convert it to electric current, OPDs function in reverse to OLEDs and are comparable to photovoltaic cells in solar panels.
The OPDs used in the new study were set up to use a Fabry-Pérot interferometer, which is made up of two curved mirrors facing each other. The OPDs were able to identify particular light wavelengths coming from the OLED array when they were positioned in this manner.
The researchers showed that even interior lighting fixtures may be equipped with the light source to transport data in a Li-Fi system by transmitting data from the transmitter to the receiver. Because their composite light source decreased interference, it also had a lower bit error rate when compared to traditional lighting.
The technique was evaluated by scientists in certain lab settings intended to reduce interference and guarantee data quality. To gain a greater understanding of the system’s functionality in real-world settings, however, they plan to test it there. The researchers pointed out in the report that there will be interference from the surrounding environment in this case, including other light and dust sources. In addition, they wish to see if the Li-Fi system functions better while the receiver is moving as opposed to fixed.
In the future, a near-infrared (NIR) channel might also help to lessen interference problems, enabling VLC transmitters to operate at longer distances. Additionally, they want to see if they can use power-line communications to overcome physical barriers like walls in a house.
