Light
Fidelity, known Li-fi, is a bidirectional, high speed and fully networked wireless
communication technology similar to Wi-Fi. Coined by Prof. Harald Haas, Li-Fi
is a subset of optical wireless communications and can be a complement to RF
communication, Wi-Fi or Cellular network, or a replacement in contexts of data
broadcasting. Visible
light communications works by switching bulbs on and off within nanoseconds,
which is too quick 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. Direct line of sight isn't necessary for Li-Fi
to transmit a signal; light reflected off the walls can achieve 70 Mbit. It is
wireless and uses visible light communication or infra-red and near
ultraviolet, instead of radio frequency waves, spectrum, part of optical
wireless communications technology, which carries much more information, and
has been proposed as a solution to the RF bandwidth limitations. A complete
solution includes an industry led standardization process. With scientists
achieving speeds of 224 gigabits per second in the lab using Li-Fi earlier this
year, the potential for this technology to change everything about the way we
use the Internet is huge. And now, scientists have taken Li-Fi out of the lab
for the first time, trialling it in offices and industrial environments in
Tallinn, Estonia, reporting that they can achieve data transmission at 1 GB per
second that's 100 times faster than current average Wi-Fi speeds. Li-Fi has the
advantage of being useful in electromagnetic sensitive areas such as in
aircraft cabins, hospitals and nuclear power plants without causing electromagnetic
interference. Both Wi-Fi and Li-Fi transmit data over the electromagnetic
spectrum, but whereas Wi-Fi utilizes radio waves, Li-Fi uses visible light. 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 much faster than typical fast broadband in 2013.
.jpg)
