Presentation on LIFI Technology.

1. Li-Fi Technology
PRESENTED BY:
 MUHAMMAD SOHAIB
 ALI HAMZA
 HASSAN MUJTABA
 MUJTABA HASSAN
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2. CONTENT
 Introduction
 Design and modeling
 Working process
 Comparison between Li-Fi and Wi-Fi
 Applications
 Advantages
 Limitations
 Conclusion
 References
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3. WHAT IS Li-Fi ?
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 Li-Fi is acronym for Light Fidelity
 bidirectional, high-speed and fully networked wireless
communication using visible light.
 Term coined by Sir Harald Haas.
 Advance form of MORSE code
 Can be called as 5G due to its speed.

4. History
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 Sir Harold Haas, coined the term "Li-Fi" at
his TED Global Talk where he introduced
the idea of "Wireless data from every light".
 He is Chairman of Mobile Communications
at the University of Edinburgh and co-
founder of pure Li-Fi.
Sir Harold Haas

5. 5

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 Limitation of IR leads us to use Visible light for communication.
 Harald Haas introduce the idea of VLC(visible light communication at TED
talk.
 Complement or may be replacement of RF.
 In 2014, recorded data transfer speed was 1.25gigabits per second.

7. Design and Modeling
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A simple Li-Fi circuit includes
 Lamp driver
 Led bulb
Photo detector
 Amplifier

8. Working Process
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 It accommodates a photo-detector to receive light signals and a signal processing element to
convert the data into 'stream-able' content.
 LED’s can be switched on and off very quickly
 Switching ON an LED is logical ‘1’ and switching OFF an LED is logical ‘0’
 Hence it is possible to encode data into the LED’s by using a controller and the rate at which LED’s
flicker depends on the data we want to encode.

9. Working Process
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10. Why Li-Fi over Wi-Fi
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SPEED
COST
SECURITY

11. Comparison between Wi-Fi and Li-Fi
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Sr-No Parameter Li-Fi Wi-Fi
Speed Now usually 10Gbps Around 150Mbps
Medium of data
transfer
Use light as medium Use radio spectrum
Spectrum range Visible light spectrum is 1000
times broad than radio
spectrum.
Smaller spectrum than
Visible light spectrum
Cost Low High
Operating frequency Hundred's of Tera byte 2.4GHz

12. Applications
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 TRAFFIC LIGHTS:
 Vehicles could communicate with one another via front and back lights to increase road safety.
 Street lamps and traffic signals could also provide information about current road situations

13. Applications
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 PUBLIC INTERNET HOTSPOTS:
 There are millions of streets lamps deployed around the world. Each of these street lamps
could be a free access point.

14. Applications
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 ON OCEANS BEDS:
 Li-Fi can even work underwater where Wi-Fi ,fails completely and open endless opportunities for
military navigation operations.

15. Applications
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 Environment:
 Visible light is more safe than RF , hence it can be use in places where RF can’t be used like
petrochemical plants.

16. Applications
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 HOSPITALS:
 to avoid interference li-Fi can be used for data communication in hospitals.

17. Applications
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AIRLINES:
 Can be used for communication in air planes.

18. Advantages
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 Higher speed than Wi-Fi(up to 10Gbps).
 More secure because data cannot be intercepted without a clear line of sight.
 Prevent piggybacking.

19. Advantages
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 Eliminate neighboring network interference.
 Not obstructed by radio interference.
 Does not create interference in sensitive electronic , making it better for use in
environments like hospitals and aircrafts.

20. Limitations
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 Presence of light is essential.
 Light cannot penetrate walls, the signal's range is limited by physical barriers.
 Works better with fluorescent light and LED’s but very low efficiency.

21. Conclusion
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 Li-Fi is fast, efficient and Economical source of communication.
 Great achievement in wireless communication.
 The possibilities are numerous and can be explored further.

22. References
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• https://www.youtube.com/watch?v=25_dIc_4JG0
• http://purelifi.com/
• https://en.wikipedia.org/wiki/Li-Fi
• http://www.techworld.com/big-data/what-is-li-fi-everything-you-need-know-3632764/

23. THANK YOU
ANY QUERIES......
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