Light-Fidelity (Li-Fi) is transmission of data using visible light by transmitting data through an led light bulb that operates so rapidly than the human eye can follow. If the led is on, The photo detector transmits a binary one; Otherwise It’s a binary zero. The idea of Li-Fi was introduced by a germen physicist, harald hass

1. KAKATIYA INSTITUTE OF TECHNOLOGY & SCIENCE &
WARANGAL
DEPARTMENT OF ELECTRICAL & ELECTRONICS EERENGINING
A
Mini project Presentation
On
LI-FI BASED WIRELESS AUDIO LIGHT TRANSMISSION
MINI PROJECT GUIDE: SUBMITTED BY:
Sri.V.Srinivas A.Madhu
Assistant Professor B17EE115
Dept of EEE 3 EEE-2

2. TABLE OF CONTENTS
 WHAT IS LI-FI?
 LI-FI OVER WI-FI
 WORKING
 ADVANTAGES & DISADVANTAGES
 APPLICATIONS
 FUTURE SCOPE
 CONCLUSION
 REFERENCES

3. ABSTRACT
Light-Fidelity (Li-Fi) is transmission of data using visible light by transmitting data
through an led light bulb that operates so rapidly than the human eye can follow. If the
led is on, The photo detector transmits a binary one; Otherwise It’s a binary zero. The idea
of Li-Fi was introduced by a germen physicist, harald hass. The term Li-Fi was first
introduced by haas in his ted global talk on visible light Communication (VLC).
According To Hass, The Light Can Produce A Higher Data Rates up to 1 giga bits per
second which is much more faster than our broadband services used today. This
prototype discusses the implementation of the basic Li-Fi based system to transmit sound
signal from one device to another. The purpose is to demonstrate Visible Light
Communication (VLC) through an led and receive the signal at the receiver through a
detector. The sound transferred by led in the form of visible light is detected at the
receiver without fading.

4. WHAT IS LI-FI?
 Light based Wi-Fi
 Light is used instead of radio waves to transmit information.
 LED lamps can light a room as well as transmit-receive
information.
 Sending data through a LED light bulb that varies in intensity faster
than human eye can follow.

5. LI-FI OVER WI-FI

6. WORKING
 Visible light is a new technique of data transmission method. Li-Fi, data is
transmitted by modulating the intensity of the light, which is then received by a
photo-sensitive detector, and the light signal is demodulated into electronic
form. This modulation is performed in such a way that it is not perceptible to the
human eye. VLC consists of a light source as a transmitter and detector as a
receiver. This electrical signal is amplified by the amplifier circuits and fed into
the power LED.
 The light signal from the LED varies according to the intensity of the voice
signal. Louder the voice, the glow of the LED will be more. At the receiver side,
Avalanche photo detector will receive the light signal and correspondingly
generate an electrical signal proportional to it. This electrical signal is processed
by a demodulator circuit, which is then fed to a speaker and it produces the
audio signal which was at the input of the transmitter side.

7. Mic
EEPROM
ADC
Audio
Amplifier
Li-Fi
drive
High Beam
Light
Local
oscillator
Channel
section
TRANSMITTER:

8. RECEIVER:
P1CI6F877A
Controller
LCD Display
UART
Converter
LIFI
Module
Rx
LDR
Power Unit
Audio
Amplifier
Speaker Relay

9. ADVANTAGES:
 Low cost
 High speed
 Low Bit Error Rate
 Portability
DISADVANTAGES:
-Nothing in this world is perfect and so does LI-FI.
These signals cannot penetrate walls. So the person needs wired bulb in that
room also.
Only works if there is direct line of sight between source and receiver.
Used for broadcast and it is difficult to uplink

10. APPLICATIONS
 Li-Fi can be used in various areas like Hospitals.
 Automation because operating rooms do not allow Wi-Fi, since Wi-Fi radiates
harmful signals.
 Li-Fi audio transmission can be used in petrochemical industries automations
where use of radio spectrum is very dangerous.
 Li-Fi can also be used in Power plants as Wi-Fi and many other radiation types
are very bad for such sensitive areas.
 Li-Fi can also be used in underwater systems for audio communications and
device control .
 Li-Fi can also be used in traffic management system for reducing the number
of accidents by vehicle to vehicle communication.

11. FUTURE SCOPE
As light is everywhere and free to use possibilities increases to a
great extent of the use of Li-Fi technology. If this technology comes to
practice each Li-Fi bulb will be used as Wi-Fi hotspot to transmit wireless
data. The concept of Li-Fi is attracting many people as it is free to use
without any licence and faster means of data transfer. If it develops faster
people will use this technology instead of Wi-Fi.

12. CONCLUSION
Using Li-Fi technology will grant a cleaner, greener and brighter future and
environment. The use of Li-Fi technology given a golden opportunity to replace or
to give alternative to the radio based wireless technologies. Thus the use of Li-Fi
will increase the speed of data transfer and also it is accessible in many
Places thus it will be available for all.

13. REFERENCES
1. http://en.wikipedia.org/wiki/Li-Fi
2. International Journal of advances in computing & communications, vol 1,
2013,page no-12 www.ijacc.org
3. Quick, Darren (2014). 10 Gbps Li-Fi System Shows Wireless Data Transfer
in New Light http://www.gizmag.com/li-fi-wireless-technology/32968/ .