Li fi – light-fidelity.
The li fi technology is a very new and was proposed by the germane physicist Harald has in 2011. The li-fi provides transmission of data through illumination by sending data through an LED light bulb that varies in the intensity faster than human eyes can fallow . In these paper the author will discuss the technology in details .
Li Fi refers to visible light communication in the manner similar to the wi fi . Li Fi provides better bandwidth , efficiency , availability and security than wi fi and has already achieved high speed in the lab.
How it work
It has implemented by the used a light bulb at the downlink transmitter. Normally the light bulb glow at the contents current supply however fast and subtle in the current can be made to produce the optical output since it just uses the light hence it can be easily applied in the aircraft and hospitals or any such area where radio frequency communication is often problematic.
The operational products is very simple , if the led is on you transmit a digital 1 , if it’s off you transmit a 0 . The LED’s can be switched on and off very quickly , which gives the nice opportunities for the transmitting data . Hence tha all that us required is some LED’s and a controller that code data into those LED’s . We have to the just very the rate at which is the LED’s ficker , depending upon the data we want to encode .
Thus the every light source will work has a hub for the data transmission.
Advantages of Li-Fi
- It is a higher speed then Wi-Fi
- The more secure as data can not be intercepted without a clear line of sight .
- It has 10,000 times wider bandwidth.
- It availability is not an issue as light is present everywhere.
- Ths comsumers less energy and highly efficient .
- It can be used in the environments like hospitals and aircrafts .
Disadvantage of Li-Fi
- The light can’t pass through objects
- The major challenge facing Li-Fi is how the receiving device will transmit back to the transmitter
- The high installation cost of the VLC system
- The interference from external light source like sun , light, normal bulb , opaque material.
- It’s uses visible light i.e LED.
- The LiFi provides 10,000 times more bandwidth or frequency spectrum of radio.
- It is high speed bidirectional network.
- cost of Lifi is about $840.
The technology is environment friendly and has immunity against electromagnetic interference.