Li-Fi uses visible light communication (VLC) to transmit data using LED light bulbs. It was pioneered in the 1990s by German scientist Harald Haas who discovered LEDs could transmit data. Li-Fi offers several advantages over traditional Wi-Fi as the visible light spectrum is much larger than the radio frequency spectrum, providing more bandwidth. It is also more secure, efficient and available in more places as light cannot pass through walls like radio waves. This makes it suitable for use in places where RF connectivity poses issues like hospitals and aircraft.

2. WHAT IS Li-Fi…..???
 Li-Fi = Light-Fidelity
 Li-Fi is transmission of data through
illumination, sending data through a
LED light bulb that varies intensity
faster than human eye can follow
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3. .
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4. HISTORY OF Li-Fi
The technology truly began during
the 1990's in countries like
Germany, Korea, and Japan
where the
German scientist discovered
LED's could be retrofitted to send
information. Prof. Harald
Haas

5. 5

6. Radio spectrum is congested but the demand for
wireless data double each year . Everything , it
seems want to use
Wireless data but the capacity is drying up !!!!
Present Scenario
1.4 Million Base
Stations
5 Billion

7. RADIO SPECTRUM
Issues ???

8. Capacity
Radiowaves
Cost and Expensive
Less Bandwidth compared
to other spectrums
Insufficient spectrum for
increasing data

9. Efficiency
Millions of base stations consume huge
amount of energy for :
1.Transmitting the radio waves
2.To cool the base station cabins
5% Efficiency

10. Availability
Available within the range of
Base stations
Limited availabity
Unavailable in aircrafts
Security
Less secure(passes through the walls)

12. Why only VLC ?
Gama rays cant be used as they could
be dangerous.
X-rays have similar health issues.
Ultraviolet is good for place without
people.
Infrared, due to eye safety regulation,
can only be used with low power.

13. HENCE WE LEFT WITH THE
ONLY THE VISIBLE - LIGHT
BUT
Who can replace Radio Waves For
Wireless Communication
?????????

14. Light-Fidelity

15. HOW LIFI WORKS ??????

16. On one end all the data on the internet will be
streamed to a lamp driver when the led is turned on
the microchip converts the digital data in form of light
.
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17. A photo detector receives the signal and converts it back
into original data. This method of using rapid pulses of
light to transmit information wirelessly is technically
referred as Visible Light Communication

18. BUT WHY LIFI NOT WIFI
????????

20. LIFI
APPLICATIONS
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21. 1-Traffic Lights :
 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.

22. 2-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 .