Light Fidelity or Li-Fi is a wireless communication technology that enables networked, bi-directional data transfer at very high speeds. It is a form of Visible Light Communication (VLC) that makes use of light waves to transmit data. This ground-breaking technology has the potential to deliver huge speed advantages and more secure communications while reducing device interference.
Laboratory experiments have shown that Li-Fi can deliver data at a speed that is 100 times faster than that of Wi-Fi. It can attain a speed of 224 gigabits per second. Both Li-Fi and Wi-Fi are similar wireless technologies that transmit data electromagnetically. But while Li-Fi uses visible light to transfer data, Wi-Fi utilizes radio waves for the same purpose.
How does Li-Fi work?
Li-Fi uses normal LED (light emitting diodes) light bulbs to transmit data at extremely high speeds. The technology behind this is as follows:
If a constant current is supplied to an LED bulb, it releases a constant stream of photons. The emitting stream of photons is seen as visible light. Now if a variation is introduced in the steady flow of current, it will impact the output intensity of the light and cause it to dim up and down. Since an LED bulb is a semiconductor device, it is possible to modulate the flow of current and the output at tremendously high speeds. A photodetector device can interpret the changes in light intensity from the LED bulb and convert the output to electrical current. The human eye cannot perceive this intensity variation. After the demodulation of the electrical signal, it is transformed into a constant stream of binary data. This binary data comprises of web, audio, video and application information that can be processed and run by Internet-enabled devices.
Interestingly, this technology enables every LED bulb to be converted into a superfast wireless router. If a small microchip is attached to the illumination devices, they would be able to perform dual functions: provide illumination as well as transmit wireless data.
History of Li-Fi technology
Li-Fi was invented by Professor Harald Haas from the University of Edinburgh in the UK. The term Li-Fi was also coined by him. He is Chair of Mobile Communications at the University of Edinburgh.
Professor Harald Haas started researching about alternative possibilities of radio frequency to transfer data in 2003. By then he had realized that the world was heading towards a radio frequency spectrum crunch. Around that time, the LED light technology was introduced in the market. He began experimenting with the electronic lighting components for data transmission at high speed.
At a TED Talk in 2011, Professor Haas drew attention to the Li-Fi technology. He presented a live on-stage demonstration of this advanced technology to the world. During the TED Talk, he envisioned that light bulbs can be used as super-speed wireless routers to transmit data. In 2012, Professor Haas co-founded PureLi-Fi, a company formed with the objective to commercialize the technology.
The idea of Li-Fi technology began to make waves after the Ted Talk in 2011. The Li-Fi Consortium was formed in October 2011. Its objective was to promote the development and distribution of superfast optical wireless systems. Since then, several countries across the world are working on the Li-Fi technology for commercial use.
Future of Li-Fi technology
Li-Fi ushers in a future of ultra-high speed wireless communication and more reliable internet connection. It will allow light to be adopted for the purpose.
The Li-Fi technology utilizes the visible light spectrum, which is free, abundant and unlicensed. It can be the solution for radio frequency bandwidth limitations. Li-Fi promises to be the pillar of communication even when the demand for data usage exceeds the available supply from current technologies such as Wi-Fi, 4G, and LTE.
With Li-Fi, wireless internet connectivity will be possible in environments that currently are not suitable for Wi-Fi connectivity. Environments such as hospitals, airplanes, and hazardous environments can benefit immensely from this technology.
Dual use of LED lighting for illumination and communication will ensure wide use of Li-Fi technology around the world.
Use of Li-Fi technology is not limited to ultra-fast networks and LED lights alone. The technology’s future will consist of light transmitters, light receivers, networking capabilities and computational algorithms that can be used in diverse communication scenarios and across different device platforms.
An interesting proposition is the use of inexpensive solar cells as a receiver for Li-Fi. Such a development can be an inexpensive way to connect a large volume of the world population that lacks access to the internet. Integration of Li-Fi and internet of things will open up a host of business opportunities as well.
Has Li-Fi mobile arrived?
Several mobile phone companies are experimenting to commercialize the Li-Fi technology and make future smartphones compatible with it. So, the future might be of mobile phones powered by Li-Fi instead of Wi-Fi.
But Li-Fi technology is in its nascent stage. Li-Fi enabled mobile phones may not be a reality before the end of the decade. Moreover, Li-Fi does have some limitations. One severe drawback is that the technology is unable to work through walls as visible light cannot penetrate walls. It makes Li-Fi a short range technology. But, this limitation makes Li-Fi more secure that Wi-Fi. It remains immune to external sniffing and suffers less interference from other devices.
Li-Fi technology does promise a very exciting future of communication and fast connections. Let’s just wait and watch!
