LIGHT FIDELITY:

Are Wi-Fi networks a thing of the past?

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	Technology does not stand still, and wireless data transmission standards that were invented not so long ago are losing ground or fading into the background. For example, wireless data transmission using Li-Fi (Light Fidelity) technology is already being developed . What this technology is and how it works is what we will try to understand today.
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A dozen years ago, we used to send pictures and music via the infrared port of mobile phones. This is a type of wireless data transfer that predates Bluebooth and Wi-Fi, but it worked on the principle of infrared radiation invisible to the eye. The main disadvantages of this technology were the low data rate and the direct connection between the transmitter and the receiver. However, it can be said that this technology gave rise to the development of wireless data transmission technology.
Another wireless light transmission technology that is still being developed and refined is Li-Fi . Using this technology, we can redefine the role of light itself. Imagine a time when every light bulb in your house is an internet source. Imagine a scenario where you download about 5 HD movies after standing under a light bulb for a minute . You will probably say that it is unrealistic… But let us try to figure out and understand how to use a light bulb to transfer data.
Li-Fi (Light Fidelity) is a fairly young technology. Its creator is German physicist Harald Haas, who used an LED lamp as a router in 2011. In laboratory conditions, he managed to achieve a transmission speed of 224 Gbps . This speed makes it possible, for example, to download 18 1.5 GB films or even 50,000 photos in one second. The idea was materialized with VLC (Visible Light Communication) technology, which allows a light source not only to act as a light source, but also to transmit information. Data transfer is carried out using LEDs whose nanosecond flickering is invisible to the human eye. A direct current is applied to the LEDs to illuminate them. The output optical signal can be modified at very high speed by rapidly changing the input current. The operation is as follows: when the LED is on, a "1" is transmitted, and when it is off, a "0".
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	The term Li-Fi refers to rapid changes in the brightness of the light emitted by an LED that are invisible to the human eye. Li-Fi is of great interest today because it uses a wide range of frequencies and wavelengths, from infrared to visible light and even ultraviolet, including gigabit communication speeds for short, medium and long distances to transfer data. The Li-Fi consortium believes that speeds in excess of 10 Gbit/s can be achieved with this optical wireless technology. For all these reasons, in a very short time the word has quickly entered the vernacular as an instantly recognizable alternative to Wi-Fi. Li-Fi could be the technology of the future, where data from laptops, smartphones and tablets is transmitted using light in a room. As such, Li-Fi is a subset of visible light communication and optical wireless communication. However, it should be noted that light spreads over a small area, which means that Li-Fi stops working once the light source disappears. The researchers and creators of this technology claim that it works up to a distance of 10 m from the source (remember that this happens under good conditions).

..:: Development of Li-Fi data transmission technology ::..

Any invention, to be accepted by the general public in the market, must be easy to use, have good performance and be reasonably priced.

Li-Fi meets this need because it uses light as a transmission medium, so it is cheap and efficient, although its initial installation requires some investment, but its subsequent maintenance is cheaper than radio wave transmission. With Li-Fi technology , power consumption is very low because light is the only receiver of electricity. Li-Fi also eliminates the effects of radio waves on health and, in addition, Li-Fi transmission uses visible light, which is not harmful in terms of health problems. So it can be said that the benefits of Li-Fi are enormous.

..:: Applications in the modern world ::..

Despite the short data transmission distance compared to Wi-Fi, Li-Fi has quite a few applications, and its use will have a much higher priority than other technologies. Let's look at some of these applications to see if this is the case:

1. Aviation. Wi-Fi is typically disabled on airplanes because it can affect aircraft instruments via radio frequencies, while Li-Fi uses light to transmit information, allowing safe use of the World Wide Web.
2. Transport and vehicles. We all know that the automotive industry is evolving every day towards intelligent vehicles that help us get around and could soon replace the driver altogether. Manufacturers hope that with this technology, cars will be able to provide warning information about sudden speed drops on motorways, road accidents, bad weather conditions and traffic jams. With the imminent arrival of self-driving cars, Li-Fi could become the standard for in-vehicle communication. With city traffic lights and motorway information boards being connected to the data transmission system, this application of the technology seems quite promising.
3. Medicine and healthcare. A special feature of Li-Fi light is that it does not cause electromagnetic interference with medical equipment. In addition, MRI scanners are not affected by the technology.
4. Public institutions, banks. Where security and transmission speed are important, the Li-Fi standard is very useful. Simply switching on Li-Fi for a short period of time is enough to transmit important information from mobile devices that cannot be intercepted.
5. Unsafe production. The use of Li-Fi technology provides a safe alternative to the electromagnetic emissions of radio communications in petrochemical plants and mines.
6. Smart lighting : Any public or private lighting installation, including street lighting, can be used as a standard Li-Fi access point using the same sensor and communications infrastructure.
7. Smart homes and offices. As for its application in the home or office, Li-Fi fits perfectly into the concept of a smart home, where we can use our smartphone to automate the operation of household appliances, workstations, blinds, heaters, locks and even furniture. Offices with a large number of employees will finally no longer have wireless communication problems.