3. INTRODUCTION
Li-Fi, or light fidelity, is 5G visible light communication systems using
light from light-emitting diodes (LEDs) as a medium to deliver
networked, mobile, high-speed communication in a similar manner
as Wi-Fi and Optical fiber.
Li-Fi could lead to the Internet of Things.
WHAT IS IT?
4. INTRODUCTION
The technology truly began during the 1990’s in
countries like Germany, Korea and Japan where
they discovered LED’s could be retrofitted to
send information.
Professor Harald Haas
Original founder of Li-Fi.
Chair of Mobile Communications at
the University of Edinburgh.
Co-founder of pureLiFi.
HISTORY
Prof. Harald Haas
University of Edinburgh,U.K
5. CURRENT SCENARIO
Radio Spectrum is congested but the demand for wireless data
double each year .Every thing, it seems want to use wireless data
but the capacity is drying up.
1.4 Million Base Stations 5 Billion
6. Current Radio Spectrum-Issues
Availability
Security
Capacity
Efficiency
Radio waves
Cost and Expensive
Less Bandwidth
compared to other
spectrums
Insufficient spectrum
for increasing data
Millions of base
stations consume
huge amount of
energy for
• Transmitting the
radio waves
• To cool the base
station cabins
• 5% Efficiency
Available within
the range of Base
stations
Limited
availability
Unavailable in
aircrafts
Less
secure(passes
through the
walls)
12. Comparision between Li-Fi and Wi-Fi
Li-Fi can be thought of as a light-based Wi-Fi. That is, it uses
light instead of radio waves to transmit information.
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.
WI-FI is great for general wireless coverage within buildings,
and li-fi is ideal for high density wireless data coverage in
confined area and for relieving radio interference issues .
So the two technologies can be considered complimentary.
13.
14. APPLICATION AREAS
LiFi Technology is still in its infancy .However some areas where
it seems perfectly applicable are:-
Traffic Lights & Flow Management:-
Traffic lights can communicate to the car and
with each other. Cars have LED-based
headlights, LED-based cack lights, and cars can
communicate with each other and prevent
accidents in by exchanging information.
DAYTIME RUNNING LIGHTS
(DRL)
15. Intrinsically Safe Environment :
Visible Light is more safe than RF, hence it can be used in places where RF can't be used
such as petrochemical plants .
APPLICATION AREAS
17. Airlines :
Whenever we travel through airways we face the problem in communication media
,because the whole airways communication are performed on the basis of radio waves.
To overcome this drawback on radio waves , li-fi is introduced.
APPLICATION AREAS
18. APPLICATION AREAS
On Ocean Beds :
Li-Fi can even wok underwater were Wi-Fi fails completely, thereby throwing open
endless opportunities for military/navigation operations.
19. APPLICATION AREAS
Street Lamps (As free Access Points) :
• There are millions of street lamps deployed around the world.
• Each of these street lamps could be a free access point.
20. LIMITATIONS & CHALLENGES
Light can't pass through objects.
Interferences from external light sources like sun light, normal
bulbs, and opaque materials in the path of transmission will cause
interruption in the communication.
Li-Fi requires line of sight.
High installation cost of the VLC systems.
A major challenge facing Li-Fi is how the receiving device will
transmit back to transmitter.
21. CONCLUSION
The possibilities are numerous and can be explored further. If this technology can be put
into practical use, every bulb can be used something like a Wi-Fi hotspots to transmit
wireless data
