LIFI Technology

A Faster and Brighter Light Fidelity

What Is LiFi?Li-Fi or Light Fidelity is basically light based

and fully networked wireless communication travelling at very high speed, technology similar to Wi-Fi.

The term was coined by University of Edinburgh Professor Harald Haas during a TED Talk in 2011. Haas envisioned light bulbs that could act as wireless routers.

Li-Fi uses common household LED (light emitting diodes) lightbulbs to enable data transfer, boasting speeds of up to 224 Gigabytes per second. Transceiver fitted in LED bulbs act like Wi-Fi modems.

Established in 2012 with Professor Harald Haas as Chief Scientific Officer, pureLiFi is a spin-out from the University of Edinburgh, where its pioneering research into visible light communication has been in development since 2008 as part of the renowned D-Light project.

Mission Statement-

“pureLiFi seeks to resolve the global struggle for diminishing wireless capacity by developing and delivering technology for secure, reliable, high speed communication networks that seamlessly integrate data and lighting utility infrastructures and significantly reduce energy consumption.”

HOW DOES IT WORK?• Li-Fi and Wi-Fi are quite similar as both transmit data electromagnetically. However, Wi-Fi

uses radio waves while Li-Fi runs on visible light.• As we now know, Li-Fi is a Visible Light Communications (VLC) system. This means that it

accommodates a photo-detector to receive light signals and a signal processing element to convert the data into 'stream-able' content.

• An LED lightbulb is a semi-conductor light source meaning that the constant current of electricity supplied to an LED lightbulb can be dipped and dimmed, up and down at extremely high speeds, without being visible to the human eye.

• For example, data is fed into an LED light bulb (with signal processing technology), it then sends data (embedded in its beam) at rapid speeds to the photo-detector (photodiode).

• The tiny changes in the rapid dimming of LED bulbs is then converted by the 'receiver' into electrical signal.

• The signal is then converted back into a binary data stream that we would recognise as web, video and audio applications that run on internet enables devices.

Advantages Of Li-FiTheoretical speed up to 1GB per second,

allowing HD movies to be downloaded in mere 3-5 seconds. Therefore, less time & energy consumption.

Mostly LED lightbulbs are used, which consumes less energy, hence cost efficient.

As light waves cannot penetrate through walls, the data cannot be intercepted. Thus provides secured communication.

Efficient and reliable alternative to radio waves based wireless as light waves will not interfere with radio waves.

Limitations Of Li-FiVisible light cannot penetrate through solid objects.

Thus, signal's range is limited by physical barriers.Internet cannot be used without a light source. This

could limit the locations and situations in which Li-Fi could be used.

Other sources of light may interfere with the signal. One of the biggest potential drawbacks is the interception of signals outdoors. Sunlight will interfere the signals, resulting in interrupted Internet.

A whole new infrastructure for Li-Fi would need to be constructed.

Applications of Li-FiIn Aircrafts, for data transmission

without causing interference with the radio equipments.

In Traffic scenario, to prevent accidents.

In Lecture Halls and Seminar rooms, for an interactive approach.

In Radio frequency restricted environment like chemical industries, nuclear power plants, petrochemical plants, etc.

In Underwater communication, where radio waves cannot propagate.

In Operation theatres, where it is difficult to lay optical fibers.

Li-Fi Vs Wi-Fi