What is Li-Fi?

Li-Fi (Light Fidelity) is a wireless data transmission technology that uses the visible spectrum of light instead of radio waves like Wi-Fi. Unlike Wi-Fi, which uses radio frequencies to transmit data, Li-Fi uses light-emitting diodes (LEDs) to create instant and powerful light signals. These light signals are then converted into digital data that can be picked up and interpreted by receivers.

The way the technology works is by using light pulses to transmit information. When LEDs turn on and off at very high speeds, this creates a sequence of light pulses that are not visible to the human eye, but can be detected by photo detectors on the receiver. The receiver then interprets these light pulses and converts them back into digital data.

The advantages of Li-Fi include high data transmission speed, potentially safer transmission of information (since light signals do not pass through walls and are not susceptible to radio interception), use of available indoor light spectra, ease and low cost of implementation, and no need for licensing.

However, the limitations of Li-Fi are its limited transmission range, dependence on line of sight between transmitter and receiver, and the effect of bright sunlight on data transmission.

Li-Fi technology is in an active research and development phase and its practical applications remain limited. However, it is of potential interest in wireless communications, especially in situations where Wi-Fi may be unsuitable or undesirable, such as hospitals, airplanes, or areas with high concentrations of electromagnetic interference.

Li-Fi proliferation

Several companies and research groups are developing and testing light wireless technology. One of the main initiators and pioneers in this field is Prof. Harald Haas from the University of Edinburgh. In 2011, he gave the first demonstration of light-based data transmission at the TED Global conference.

Since then, several companies have released prototypes and products based on Li-Fi technology. One such company is Velmenni, an Estonian startup company that in 2015 conducted the first commercial tests of Li-Fi in an office environment. Their Li-Fi system was able to achieve data rates of up to 1 Gbps.

Another company, Signify (formerly known as Philips Lighting), is also actively working on developing the technology. They have introduced a product called Philips LiFi, which combines LED lighting with the ability to transmit data via light pulses. Philips LiFi offers higher data rates and is considered one of the main commercial products in the Li-Fi market.

In addition, there are other research groups and startups that are working on the development and commercialization of Li-Fi technology. Overall, although Li-Fi is still in the development stage and is not widespread, it represents potential promise in wireless communications and has the opportunity to become an alternative or complement to existing data transmission technologies.

Recently, the Institute of Electrical and Electronics Engineers added 802.11bb as a standard for light-based wireless communications. Formalization of the 802.11bb standard will accelerate the diffusion and adoption of the light-based data communications technology standard.