What is LiFi?
Li-Fi is a wireless data communication technology that uses Light Emitting Diodes (LEDs) to transmit data via light.
Li-Fi - Wikipedia gives the following description: Li-Fi(Light Fidelity) is a wireless internet connection that works based on LEDs. The system, developed by German professor Harald Haas in 2011, is equivalent to WiFi, but could work 100 times faster.
There are 1.4 million cellular radio masts (base stations) operating worldwide. There are also more than 5 billion cellular mobile phones in use worldwide. These mobile phones transmit more than 600 terabytes of data every month. Wireless communication has now become a utility like electricity and water. We use it every day both in our private lives and in business. This raises issues because communication is so fundamental to our modern lives. One of the problems is capacity. We transmit wireless data using electromagnetic waves to be precise, radio waves. Radio waves have their limitations, they are scarce and expensive. It is these limitations that make it impossible to meet the increasing demand for wireless data transmission. The suitable part of the electromagnetic spectrum is too small for this purpose.
There is another problem and that is efficiency. The 1.4 million cellular radio masts consume a lot of energy. Most of that energy is used not to transmit radio waves but to cool the base stations. The efficiency of such a base station is only about five per cent. Another problem that everyone seems to be increasingly aware of is availability. For instance, you have to switch off your mobile phone on the plane. Safety (both security and privacy) is another issue. In hospitals, radio waves are a security risk. Radio waves penetrate walls and can be intercepted, someone with bad intentions can use your network.
Electromagnetic spectrum
There are 14 billion light bulbs in use worldwide. Light is a part of the electromagnetic spectrum. Let's look at this in the context of the entire electromagnetic spectrum. With gamma radiation, you don't want to get too close because it is dangerous. X-rays (x-rays) are useful in hospitals. Then there is ultraviolet light, fine for a nice tan but dangerous for the human body. Infrared light can only be used at low power due to safety regulations for the eye. The problems of radio waves have been discussed above.
At the centre of the spectrum is visible light. It is that light to which we have been accustomed for many millions of years. In fact, it created us, life, and everything that lives. So it is inherently safe to use. Wouldn't it be great to use just that light for wireless communication? The size of the visible-light spectrum compared to the radio wave spectrum is 10,000 times larger. There are 1.4 million expensive inefficient cellular base stations using radio waves. Multiply that by 10,000, and you arrive at 14 billion. 14 billion is the number of lights already installed, so we have the infrastructure. All we need to do is replace inefficient incandescent bulbs with LED bulbs. A light emitting diode (LED) is a semiconductor and has a very interesting property. The intensity of LED lamps can be switched on and off at extremely high speeds. This is a fundamental basic property for using LiFi technology.
A great example using the visible-light spectrum is remote controls. A remote control uses an infrared LED. Basically, you switch the LED on and off. The LED provides a simple low-speed data stream at around 10,000 to 20,000 bits per second. However, this is not fast enough for streaming a video, for example. With Li-Fi, not only a single data stream is sent, but thousands of parallel data streams are sent at high speeds. The lamp has to stay on to send data but you can dim it to a level that it appears to be switched off. This signal processing technology allows LED light sources to transmit data (data). A small microchip can be attached to each LED light source. This then combines two basic functions; lighting and wireless data communication. Li-Fi will solve the four essential problems of today's wireless communication. In the future, there will be not only 14 billion lamps but also 14 billion Li-Fi's for a cleaner, greener and even better future.
Telecom Agency: LiFI and Infrared are useful complements to WiFi (Tweakersnet article)
LiFi applications
The applications of Li-Fi go far beyond what we can currently imagine. Within a few years, Li-Fi will be integrated into smartphones. Li-Fi can be used in hospitals for new medical instruments. Traffic lights can communicate with self-driving cars. Cars have LED headlights and LED tail lights this allows cars to communicate with each other and prevent accidents by the way they exchange information.
- Capacity: LED lights are used all over the world, and all these lights can be equipped with Li-Fi.
- Efficiency: LED lamps are very energy-efficient, add to this the free transfer of data and you have the ideal combination.
- Availability: There is light everywhere, in hospitals, in planes on your smartphone (LED lamp). These are all potential sources for high-speed data communication.
- Security: There is data only where there is light, it cannot pass through walls. When sending secure data, the direction determines where the data goes.
