What is Li-Fi and How It Works....
Li-Fi, or Light Fidelity, is a
technology, that can be a complement of RF communication (Wi-Fi or Cellular
network), or a replacement in contexts of data broadcasting. Li-Fi, like Wi-Fi,
is the high speed, bidirectional and fully networked subset of visible light
communications (VLC). It is wireless and uses visible light communication
(instead of radio frequency waves), that is part of the Optical Wireless
Communications technologies, which carries much more information, and has been
proposed as a solution to the RF-bandwidth limitations.
It is a 5G visible light
communication system that uses light from light-emitting diodes (LEDs) as a
medium to deliver networked, mobile, high-speed communication in a similar
manner as Wi-Fi. Li-Fi could lead to the Internet of Things, which is
everything electronic being connected to the internet, with the LED lights on
the electronics being used as Li-Fi internet access points.[4] The Li-Fi market
is projected to have a compound annual growth rate of 82% from 2013 to 2018 and
to be worth over $6 billion per year by 2018.
Visible light communications
(VLC) works by switching bulbs on and off within nanoseconds, which is too
quickly to be noticed by the human eye. Although Li-Fi bulbs would have to be
kept on to transmit data, the bulbs could be dimmed to the point that they were
not visible to humans and yet still functional. The light waves cannot
penetrate walls which makes a much shorter range, though more secure from
hacking, relative to Wi-Fi.[8][9] Direct line of sight isn't necessary for
Li-Fi to transmit signal and light reflected off of the walls can achieve 70
Mbit/s.
Li-Fi has the advantage of being
able to be used in electromagnetic sensitive areas such as in aircraft cabins,
hospitals and nuclear power plants [citation needed] without causing
electromagnetic interference. Both Wi-Fi and Li-Fi transmit data over the
electromagnetic spectrum, but whereas Wi-Fi utilises radio waves, Li-Fi uses
visible light. While the US Federal Communications Commission has warned of a
potential spectrum crisis because Wi-Fi is close to full capacity, Li-Fi has
almost no limitations on capacity.
The visible light spectrum is
10,000 times larger than the entire radio frequency spectrum. Researchers have
reached data rates of over 10 Gbit/s, which is more than 250 times faster than
superfast broadband. Li-Fi is expected to be ten times cheaper than Wi-Fi.
Short range, low reliability and high installation costs are the potential
downsides.