Have you ever got frustrated at the slow speed of the Wi-Fi when more than
one device is tapped into the network? Have you already tried to use wireless
internet in a coffee shop or to steal it from your neighbour? Nowadays, more
and more people and their many devices have access to wireless internet;
clogged airwaves are going to make it increasingly difficult to latch onto a
reliable signal. But many people don’t know that radio waves are just one part
of the spectrum that can carry our data. What if we could use other waves to
surf the internet and transmit or receive data?
Li-Fi is a technology promised since 2011; Light Fidelity offers the perspective of a replacement, at
least partially, of Wi-Fi; with more flow and without the waves feared by many
people because of their harmfulness.
What is Li-Fi?
Like Wi-Fi,
it’s a method of transmitting data from one point to another wirelessly.
Whereas Wi-Fi uses radio waves, Li-Fi uses light to communicate
data.
The
operation of Li-Fi is quite easy to understand. It works with the transmission of a binary
message due to the lighting and the extinction of a light. Therefore, it’s not
difficult at all and that’s exactly what we need to end and receive data: light
off is equivalent to 0 and light on is equivalent to 1.
In fact, we can say that Li-Fi is a sort of
light-based Wi-Fi. The difference between them is that Li-Fi uses light instead of radio waves to transmit information. And instead of
Wi-Fi modems, Li-Fi would use transceiver-fitted LED lamps that can light a
room as well as transmit and receive information. Moreover, Li-Fi use simple bulbs. That’s the reason why there can be any number of access
points.
This new technology uses a part of the electromagnetic spectrum (The
Visible Spectrum). Nevertheless, it’s still not greatly utilized. As you know,
light is a very important part of our lives and it does not have any major
negative effects. It is possible to encode data in the light by varying the
rate at which the LEDs flicker on and off to give different strings of 1s and
0s. The LED intensity is modulated very quickly so that human eyes cannot
notice. Therefore the output appears constant. It is the fast and cheap
Wireless communication system which is an optical version of Wi-Fi.
LEDs:
Light-emitting diodes
are the next big thing in the lighting world. Efficient and long-lasting,
they’re already replacing filament and halogen lighting.
Working process:
Frequency changes which are very fast are not visible to the human eye. Li-Fi is a system of wireless
transmission of data using light as a medium of communication. A Li-Fi router feeds the lighting system.
The LED bulb turns on and off at very High speed. An integrated sensor receives
data. Photodetector registers a binary ‘1’ for on else its’0’ for off. The
operational procedure is very simple, if the LED is on, you transmit a digital
1, if it’s off you transmit a 0. The LEDs can be switched on and off very
quickly, which gives nice opportunities for transmitting data. Binary
information is made up of strings of 1’s and 0’s. Any light source can transmit
this ON and OFF information but LEDs are capable of the highest flickering
speed. Light receivers interpret the flickering LED as 1’s and 0’s, and thus we
have our Li-Fi.
Light off = 0 Light on = 1
Why is Li-Fi so much faster?
Visible light is far denser than radio waves; 10,000 times denser in
fact, meaning much more data can be transferred.
Some figures:
3,4 billion internet
users
19 billion global
networks connections (mobile and fixed)
The global mobile
data traffic will weigh 10,8 Exabytes per month.
A powerful
technology:
With Li-Fi, a LED light can transmit
multimedia content (video, sound, information, games, etc.) to a tablet or a
smartphone.
No interference:
Increased security of
communication
Wireless
communication at very high speed
Multi-user
communication
What’s so special
about Li-Fi?
The speed! The
highest speed yet recorded with a Li-Fi connection is 10
Gbit/s which is 250 times faster than the average Broadband speed. But
commercial Li-Fi being produced in China is at about 150Mbps which is still 10 times
higher than the average French connection speed.
Advantages:
New ultra-fast and
secure communication network without cable, without radio waves, simply by the
light! Also: smart lighting network, wireless, internet access, media access.
Transport:
During your travels,
you have access to the Internet. Li-Fi can be used safely on planes because it does not interfere with radio equipment.
Hospitals:
Connections are
possible in a place hostile to radio waves.
Traffic:
Allows vehicles (car
headlights) to transmit information to secure the traffic and make it more
fluid. Measuring distances between vehicles.
Security:
Sending and receiving
data via the LED light. Very high speed communication within military vehicles:
cars, planes, boats, submarines.
Hazardous environments:
Access your
communications in a difficult or dangerous environment: tunnel, factory,
petrochemical, refinery, etc.
However, this new
technology has some drawbacks :
Presence of light is
one of the keys for the good working of Li-Fi.
Fluorescent light and
LEDs are optimal to use Li-Fi but these lights possess a low lightning.
Li-Fi &
Wi-Fi…
We can say that
Wi-Fi is perfect for wireless coverage within buildings; Li-Fi is great for
high density wireless data coverage in restricted areas and for abating radio
interference problems. To conclude Li-Fi and Wi-Fi can be
considered complimentary.
Conclusion
Li-Fi is an amazing
technology. It’s also in its early days. It’s hard to predict how a technology
will develop over time, but it’s safe to say that a combination of Li-Fi
and Wi-Fi
will bring the best of both worlds to the internet.
