Li-Fi is a wireless communication technology that uses light from LED bulbs to transmit data. It provides bidirectional communication at very high speeds of up to 224 Gbps. Li-Fi was coined by Harald Haas and builds upon prior visible light communication research. It works by switching LED bulbs on and off very fast to transmit digital signals and can provide localized connectivity in areas where radio frequencies are regulated. While Li-Fi has advantages like extremely high speeds and no interference, it also has limitations such as an inability to pass through objects and the need for line of sight communication. Potential applications include enhanced cellular connectivity, use in hazardous environments, and smart lighting systems.

1. 12 May 2020 1
K. K. WAGH EDUCATION SOCIETY
PROFESSIONAL PRACTICES TWO
[PPT]
Group Members :- Jagruti Patel(26)
Nikul Patel(28)
Jay Pasi(27)
Atharva Shahane(36)
CLASS : - SYCM-SS (4th semester)
Light Fidelity(Li-Fi)

2. Presentation Overview
• Introduction
• History
• How Does Li-fi Works
• Real Time Usage Of Li-fi
• Other Technology
• Li-Fi Vs. Wi-Fi
• Advantages
• Disadvantages
• Application
• Conclusion
• References

3. INTRODUCTION
• Li-Fi is a bidirectional, high speed and fully
networked wireless communication technology similar
to Wi-Fi.
• The term was coined by Harald Haas.
• Li-Fi is a form of visible light communication and a subset
of optical wireless communications (OWC) and could be a
complement to RF communication (Wi-Fi or Cellular
network), or even a replacement in contexts of data
broadcasting.
• It is so far measured to be about 100 times faster than
some Wi-Fi implementations, reaching speeds of
224 gigabits per second.

4. HISTORY
• Harald Haas, who teaches at the University of Edinburgh in the UK, 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 pureLiFi. The general term visible light communication(VLC),
whose history dates back to the 1880s, includes any use of the visible light
portion of the electromagnetic spectrum to transmit information.
• The D-Light project at Edinburgh's Institute for Digital Communications was
funded from January 2010 to January 2012. Haas promoted this technology in
his 2011 TED Global talk and helped start a company to market it.
• Pure LiFi, formerly pure VLC, is an original equipment manufacturer(OEM)
firm set up to commercialize Li-Fi products for integration with existing LED-
lighting systems. In October 2011, companies and industry groups formed
the Li-Fi Consortium, to promote high-speed optical wireless systems and to
overcome the limited amount of radio-based wireless spectrum available by
exploiting a completely different part of the electromagnetic spectrum.

5. HISTORY cont..
• A number of companies offer uni-directional VLC products, which is not
the same as Li-Fi - a term defined by the IEEE 802.15.7r1 standardization
committee.
• VLC technology was exhibited in 2012 using Li-Fi. By August 2013, data
rates of over 1.6 Gbit/s were demonstrated over a single color LED.
• In October 2013, it was reported Chinese manufacturers were working on
Li-Fi development kits.
• In April 2014, the Russian company Stins Coman announced the
development of a Li-Fi wireless local network called BeamCaster.
• Their current module transfers data at 1.25 gigabytes per second but they
foresee boosting speeds up to 5 GB/second in the near future.
• In 2014 a new record was established by Sisoft (a Mexican company) that
was able to transfer data at speeds of up to 10 GB/s across a light
spectrum emitted by LED lamps.

6. HOW LI-FI WORKS
• The Functioning Of LI-FI is Very Simple.
• Uses LED And Photo-Detector For Data
Communication.
• Photo Detector Receives Binary 1 When LED is
ON And Receives Binary 0 When LED IS OFF.
• Now Just Imagine Of A Number Of LED’s Together
Flashing Light On Photo Detector Creating A
Proper Message.
• Combination Of GREEEN AND RED Laser Is Able
To Transfer Data with 1 GBPS Speed.

7. How Is It Different.

8. REAL TIME USAGE OF LI-FI
• Data communication
• Internet connectivity
• Partial replacement of Wi-Fi
• Underwater lines
• Mapping

9. OTHER TECHNOLOGIES
• BLUETOOTH : A wireless data communication
between devices on small power
consumption.
• WI-FI : A wireless communication medium
based radio frequency.
• NFC : Near Field Connection.

11. WI-FI VS LI-FI
Feature LiFi WiFi
Full form Light Fidelity Wireless Fidelity
Operation
LiFi transmits data using
light with the help of LED
bulbs.
WiFi transmits data using
radio waves with the
help of WiFi router.
Interference Do have interferences.
Will have interference
issues from nearby
access points(routers)
IEEE Standard IEEE 802.15.7r1 IEEE 802.11

12. WI-FI VS LI-FI conti…
Data transfer speed About 1 Gbps
WLAN-11n offers
150Mbps, About 1-2
Gbps can be achieved
using WiGiga/Giga-IR
Frequency of operation
10 thousand times
frequency spectrum of
the radio
2.4GHz, 4.9GHz and
5GHz
Data density
Works in high dense
environment
Works in less dense
environment due to
interference related
issues
Coverage distance About 10 meters
About 32 meters (WLAN
802.11b/11g), vary based
on transmit power and
antenna type

13. ADVANTAGES
• Overcome the inefficiency of radio frequency
bandwidth.
• High DTR i.e., up to 10 Gbps can be achieved.
• Provide security to the piconet.
• Low Implementation and maintenance cost.

14. DIS-ADVANTAGES
• Light cannot penetrate through the objects.
• High cost of installation of VLC systems
• Interference from external lights like sun light,
bulbs etc.,.

15. APPLICATIONS
• RF Spectrum Relief.
• Mobile Connectivity.
• Hazardous Environment.
• Aviation.
• Under Water Communication.
• Location Based Services(LBS).
• Smart Lighting.

16. CONCLUSION
• LI-FI Has Made A Very High Speed Data
Sharing Possible i.e., upto 10gbps.
• Tough there are limitations to this technology
there are a number of advantages.
• LI-FI Technology Would Not Completely
Replace WI-FI Technology In Decades.

17. References
• www.lifi-center.com
• www.wikipedia.com
• www.techworld.com
• www.ibtimes.com
• www.youtube.com