LiFi uses visible light communication between 400 and 800 terahertz. Data is transmitted by modulating the light's intensity in LED bulbs. The signal is received by a photosensitive detector, and converted into electronic form. The modulation in the LED bulb takes place so fast that it is not visible to the human eye. Because LED bulbs are semiconductor devices, the current, and hence the optical output, can be modulated at extremely high speed.
Here are some applications of LiFi:
* freeing up spectrum: if traffic from radio spectrum is diverted to LiFi, already clogged cellular networks will be relieved of burden.
* smart lighting: street lamps can be used to provide LiFi hotspots
* hospitals: LiFi does not result in any electromagnetic interference, and will not interfere with medical equipment
* transportation: LiFi can be used for vehicle-to-vehicle and vehicle-to-roadside communication for road safety and traffic management.
Here are some of the disadvantages:
* light cannot pass through walls, so mobility is an issue
* LiFi cannot be achieved without a light source
