What is Li-Fi and what is it used for

Li-Fi technology uses LED light bulbs to send data packets at very high speeds. Here's how it works and where you can use it

Wireless communication standards are a dime a dozen, each with features and functionality suited for a specific purpose. There are those for long-range communications (such as 4G LTE), those for medium-range (WI-FI) and those for short-range (such as Bluetooth).

All those we use today (and will use in the near future, such as 5G) exploit radio waves, of varying lengths and frequencies, to allow users to exchange voice and data packets. In some time, however, we may be able to leverage light pulses to create wireless networks inside even large enclosed spaces. Or, at least, this is what the creators of Li-Fi technology (acronym for Light Fidelity) hope, a system that uses normal LED bulbs instead of a band of the radio spectrum. After years of tests and trials, in fact, it seems that the technology is ready to be used on a large scale.

What is Li-Fi

As mentioned, this is a technology that uses LED bulbs that emit high-frequency light pulses and thus able to replace radio waves. The principle of operation is, broadly speaking, the same as fiber optics, but Li-Fi is designed for wireless connections and uses "normal" LED bulbs, while the first is designed for wired connections and uses laser pulses to send data packets.

How Li-Fi works

From a purely theoretical point of view, Li-Fi could work in the spectrum of ultraviolet light, both in that of infrared light, both in the spectrum of visible light. The latter, however, is so wide (10 thousand times larger than the entire radio spectrum) that companies and scientists have focused on developing the wireless communication protocol using LED bulbs.

Basically, the operation of a Li-Fi network is all in all simple. The bulbs in the network emit light pulses at a very high frequency, so that the human eye does not notice any difference and the visual system is not "disturbed" by this behavior. At the same time, however, the "invisible" pulses send data packets to devices that are compatible with the standard.

The latter, equipped with ad hoc photoreceptors, receive the light signal, "interpret" it and send data packets in turn using a light source (the LED flash of a smartphone camera, for example). To manage the exchange of packets a special chip that must be implemented on the bulbs that will form the wireless network "light".

The advantages of Li-Fi

As it is thought and could be configured, Li-Fi would provide significant advantages over Wi-Fi. First of all, it could be implemented within a normal lighting system, without the need for additional wiring and with a not too high expense. It would also be able to manage a greater number of devices, ensuring a connection speed far superior to Wi-Fi. In lab tests, Li-Fi reached speeds of 223 gigabits per second, while the current Wi-Fi standard is just over 1 gigabit. Li-Fi is also immune to electromagnetic noise and can be used in environments where Wi-Fi could cause interference with other technologies that use the same data band.

What is Li-Fi for

Li-Fi was created to be used indoors, so as to maximize its efficiency. For example, it could become a valid alternative to Wi-Fi inside offices, where it would be enough to replace the light bulbs used with LED bulbs compatible with the standard to have a high-speed, ultra-wideband wireless network. Its characteristics, however, also make it suitable for use within a smart home, where it could easily manage communications between the various devices in the house.