This document provides an overview of Li-Fi technology presented by Koteshwar Rao M. It defines Li-Fi as using LED light bulbs to transmit data by varying the intensity of light faster than the human eye can detect. Li-Fi uses visible light spectrum for communication. It has advantages over Wi-Fi such as higher speed, more bandwidth, more secure connections, and energy efficiency. Potential applications of Li-Fi include use in airlines, power plants, underwater environments, and converting every light bulb into an internet hotspot. Further enhancements may enable speeds over 10Gb/s.

1. SEMINAR ON
LI-FI
Under the guidance of
Asst. prof GIRISH KUMAR D
Presented by
KOTESHWAR RAO M
(3BR11IS017)

2. WHAT IS LI-FI?
 LI-FI is transmission of data through illumination,
i.e. sending data through a LED light bulb that
varies in intensity faster than human eye can
follow
 LI FI- LIGHT FIDEALITY

3. INTRODUCTION
Li-Fi is now part of visible light communication
(VLC).
Professor Harald Haas, from the University of
Edinburgh in the UK, is widely recognized as the
original founder of Li-Fi. He coined the term Li-Fi
and is Chair of Mobile Communications at the
University of Edinburgh and co-founder of pure LiFi.

4. Continued…
 In simple terms, Li-Fi can be thought of as a light-based
Wi-Fi.
 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.

5. PRESENT 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 5 Billion

8. Radio
Waves
Infrared
Rays
Visible
Rays
Ultraviolet
Rays
X- Rays
Gama
Rays
 Gama rays cant be used as they could be
dangerous.
X-rays have similar health issues.
Ultraviolet light is good for place without people, but
other wise dangerous for the human body.
Infrared, due to eye safety regulation, it can only
used with low power.
HENCE WE LEFT WITH THE ONLY THE VISIBLE - LIGHT SPECTRUM.

11. How LI-FI Works?

14. LI FI CONSTRUCTION
The LI FI product consists of 4 primary sub-
assemblies:
• Bulb
• RF power amplifier circuit (PA)
• Printed circuit board (PCB)
• Enclosure

16. Characteristics WI-FI LI-FI
Frequency 2.4GHz to 5GHz No frequency for light
Standard IEEE 802.11 IEEE 802.15
Range 100m Base on LED light
Primary application Wireless local area
networking
Wireless local area
networking
Data transfer rate 11Mbps >1Gbps
Power consumption Medium Low
Cost Medium High
Security Its medium secure Its high secure
Primary devices Notebook computers,
desktop
computers, servers, TV,
Latest Wi-Fi
mobiles
Mobile phones, office and
industrial
automatic devices,
notebook
computers, desktop
Comparison of Wi-Fi & Li-Fi.

18. Long service life (10-15 years while usual bulbs last 1-2
years)
Energy Saving (8W LED bulb=60W ordinary Bulb)
Light emitting Diodes are a source of light (release large
amount of energy in the form of light)
Can be switched on/off at very high speed
Energy Efficiency
High speed data transfer
It’s main advantage is it’s bandwidth, It is 10,000 times
than the radio waves
Cost Benefits
Advantages of LI-FI Technology

19. Disadvantages of LI-FI technology
 The main drawback in LI-FI is power consumption.
 Light signals not easily move just like as radio signals
they will follow certain path so it is also draw back of
LI-FI.

20. Application area of LI-FI technology
1. Health Technologies
2. Airlines
3. Power plants
4. Under sea working
5. Various other areas
6. Green Information technology
7. Increase Communication safety
8. Multi User Communication
9. Lightings points used as Hotspot

21. Conclusion
 Possibilities for future utilization are abundant.
Every light bulb can be converted into li-fi signal
receptor to transfer data and we could proceed toward
the cleaner, safer, greener and brighter future.
 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.

22. FUTURE ENHANCEMENT
 Further enhancements like using an array of LEDs for
parallel data transmission or using mixture of red,
green and blue LEDs to alter the light’s frequency with
each frequency encoding a different data channels can
be made.
 Such advancements promise a theoretical speed of 10
Gb/s- means one can download a full high definition
film in just 30 seconds.

23. Reference
 M. Afghani, H. Haas, H. Elgala, and D. Knipp, “Visible
Light Communication using OFDM” in Proc. of the
2nd International Conference on Testbeds and
Research Infrastructures for the Development of
Networks and Communities (TRIDENTCOM),
Barcelona, Spain, March 1-3 2006, pp. 129-134.
http://www.electronicsforu.com/electronicsforu/circu
itarchives/view_articl asp?sno=778&title%20=%20Li-
Fi%3A+A+New+Paradigm+in+Wireless+Communicati
on&b_type=new&I =12042
 http://en.wikipedia.org/wiki/Li-Fi

24. THANK YOU