Li-Fi (Light Fidelity) Technology

3. Present Scenario

We have 1.4 million cellular base stations deployed

We

Mobile phones transmit 600TB of data every month

Wireless communication has become an utility like
also
have
5
billion
of
mobile
phones
electricity and water

We use it in our everyday life, private life, business life
as currently 2G, 3G, 4G uses radio waves

4. History

5. Dr. Herald Haas

6. Issues with radio waves
Capacity
Efficiency
Availabilit
y
Security

7. Radiowaves Issue : Capacity

We transmit wireless data through radio waves.

Radio waves are limited.

Radio waves are scarce and expensive.

We only have certain range of it.

With advent of new technologies like 3G, 4G we are
running out of spectrum.

8. Radiowaves Issue :Efficiency

There are 1.4 million cellular radio base stations.

They consume massive amount of energy.

Most of this energy is not used for transmission but for cooling
down the base stations.

Efficiency of such a base station is only 5% and that rise a big
problem.

9. Radiowaves
Issue :Availability

Availability of radio waves or RF signals causes another concern.

We have to switch off mobile phones in airplanes.

Radio waves cannot be used under water

It is not advisable to use mobiles at places like petrochemical
plants and petrol pumps, nuclear power plant etc.

10. Radiowaves Issue :Security

Radio waves penetrates through walls.

They can be intercepted.

If someone has a knowledge and bad intentions then he may
misuse it.

12. Li Fi

13. Alternative to Radiowaves in EM
Alternative to Radio Waves in Electromagnetic spectrum

Looking at EM spectrum.
RadioWaves






InfraWaves
Visible
Rays
UltraViolet
X-rays
Gamma
Rays
Gamma rays are simply dangerous and thus can’t be used for our
purpose of communication.
X-rays are good in hospitals and can’t be used either.
Ultra violet rays are sometimes good for our skin but for long
duration it is dangerous.
Infrared rays are bad for our eyes and are therefore used at low
power levels.
We have already seen the short comings of radio waves.
So we are now left with Visible Rays.

14. Light for Wireless communication

Light has been around us for millions of years

It has created us, has created life and has created all stuffs of life.

Light is part of electromagnetic spectrum

There are 40 billion light box already installed

Li-Fi uses rapid pulses of light to transmit information wirelessly.

It is inherently safe to use and would be great if we can use it for
our wireless communication.

15. The LiFi product consists of 4 primary sub-assemblies:
1.Bulb
2.RF Power Amplifier Circuit (PA)
3.Printed Circuit Board (PCB)
4.Enclosure
1. The high concentration of energy in the electric field vaporizes the
contents of the bulb to a plasma state at the bulb’s center; this
controlled plasma generates an intense source of light.
2. The PCB controls the electrical inputs and outputs of the lamp and
houses the microcontroller used to manage different lamp functions.
3. An RF (radio-frequency) signal is generated by the solid-state PA
and is guided into an electric field about the bulb.
4. All of these subassemblies are contained in an aluminum enclosure.

16. How It Works..???




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 this digital data in the
form of light.
On the other end this light is detected by photo sensitive devices.
Next this light is amplified and processed and then fed to the device.

17. How It Works..???

18. Procedure Map Of LiFi

19. Model Prototype Of LiFi

20. Model Prototype Of LiFi

21. How it Works?
21

22. Traffic Control By LiFi

23. Home with LiFi

24. Advantages of LiFi







You Can Use Li-Fi In Hospitals And
Aircrafts Also.
Cheaper Then WiFi , Since Visible Light
Spectrum Is A Free Spectrum Band.
No License Needed.
Thousands And Millions Of Street
Lamps Can Be Converted To Li-fi Spots.
Light Is Readily Available In Every Part
Of The World.
This Makes It Easy For People In
Airplanes To Work On The Internet.
There Are An Estimated 14 Billion Light
Sources On Earth And Each Can Be
Easily Converted Into A Li-Fi Hotspot.

25. Advantages of Li-Fi
Other Advantages of Li-Fi Technology
Capacity
10000times more spectrum than Radio waves.
Light box are already present.
We have the infrastructure available and already installed.
Efficiency
Data through illumination and thus data transmission comes
for free.
Led light consumes less energy.
High efficient.

26. Advantages of Li-Fi
Availability
Light is present everywhere.
Can be used in airplanes.
It can be underwater where radio waves cannot.
Security
Light waves doesn’t penetrate through walls.
Can’t be intercepted and misused.
Data is present where there is light.

27. Limitations of LiFi

There should be line of sight between sender and receiver

Visible light cannot penetrate through solid objects

Interference with other electromagnetic waves makes the
transmitting data to distort
Light cannot approach the range and penetration of radio waves
High installation cost of the VLC systems
A major challenge facing Li-Fi is how the receiving device will
transmit back to transmitter.
Interferences from external light sources like sun light, normal
bulbs, and opaque materials in the path of transmission will cause
interruption in the communication.





28. LiFi is Proven or Not ?
Is it a proven technology?

Yes, this is already proven.

Dr. Harald Hass demonstrated his invention using an ordinary table
lamp that successfully transmitted data at speeds exceeding
10Mbps .

To prove that the light bulb was the source of data stream, he
periodically blocked the beam of light, causing the connection to
drop.

29. Video Demonstration of LiFi
Li-Fi Demonstration by Harald Hass at TED talk, 2013

30. Applications of LiFi

Can be used in the places where it is difficult to lay the optical
fiber like hospitals. In operation theatre Li-Fi can be used for
modern medical instruments.

In traffic signals Li-Fi can be used which will communicate with
the LED lights of the cars and accident numbers can be decreased.

Thousands and millions of street lamps can be transferred to Li-Fi
lamps to transfer data.

In aircraft Li-Fi can be used to transmit data.

It can used in petroleum or chemical plants where other
transmission or frequencies could be hazardous.

31. 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 Wi-Fi
hotspot to transmit wireless data and we will proceed
onwards the
Cleaner, Greener, Safer and Brighter future.

32. Questions