Imagine this. You woke up in the morning and touched your smart phone to switch on your coffee machine, when going for office, your car indicates you about the traffic on particular road and at night while sleeping, your blanket itself adjust the temperature under it according to the weather outside. This phenomenon is known as “Internet of Things”, which is an optical communication technology that’s taking the world by storm.
Now while using wireless internet at own place, or just peeping to some other’s network, one has probably got frustrated because of slow speed of internet when more devices are connected to a single router. Though Wi-Fi gives us speed upto 150mbps as per IEEE 802.11n, it is still insufficient to accommodate number of desired users. To remedy this limitation of Wi-Fi, a German physicist Harold Hass introduced the concept of Li-Fi technology, to which he called D-Light-“data through illumination “, talking the fiber out of the fiber optics by sending through an LED light bulb that varies in intensity faster than the human eye can follow. It’s the same idea band behind infrared remote controls but far more powerful.
Li-Fi stands for-Light Fidelity, the term some have used to label fast and cheap wireless communication system. It is an optical version of Wi-Fi.
With Li-Fi, data hitches a ride along a spectrum of visible light- Light Emitting Diodes-LED bubs, transmit data when they are switched on and off so rapidly in nanoseconds, that the human eye cannot see it. It can be better explained as- there is light emitter (LED) at one end, sender side and a photo detector on other, receiver side. The photo detector registers binary 1 if the LED is ON, and a binary 0, if the LED is OFF. To build up a message, flash the LED numerous time or use an array of LEDs or perhaps a few different colors; red, blue, green each having a different data channel. This quick flickering of light gives a very good opportunity for transmitting data through light. This particular phenomenon of transmission of data through fast pulse of light is known as Visual Light Communication(VLC). Such advancement promises a theoretical speed of 10gbps- meaning we can download a full high definition film in just 30 seconds.
The vast availability of LED bubs will drive the future ubiquity of connectivity even in places where Wi-Fi fails- on an airplane and in submarines. Another advantage of Li-Fi is zero electromagnetic interference, allowing connectivity even in areas where Wi-Fi is not accepted like hospitals and nuclear power plants. In addition, Li-Fi offers better data defense as light wave can’t pass through the walls, making it impossible to hack any internal systems in high security buildings. As Li-Fi is a visible light communication medium, so it does not require any kind of spectrum license i.e we don’t need to pay any amount for communication and license.
Moreover Li-Fi never gives any side-effects on any living thing like radio waves and other communication waves which effects on the birds, human bodies etc. as radio waves used by Wi-Fi gets more congested and the demand for faster and more efficient wireless communication escalates, the future is bright for Li-Fi as a reliable, affordable and more secure solution.
(The author is an engineer ME(IT)