Hi

1. Presentation on…
LI-FI (LIGHT FIDELITY)
DATA TRANSFER
UNDER THE GUIDANCE OF
PROF. SAGNIKA BHATTACHARYA
HOD – Department of Electrical Engineering
GLOBAL INSTITUTE OF MANAGEMENT AND TECHNOLOGY

2. LIGHT FIDELITY DATA TRANSFER
Presentation By:
1. Alif Sha Alam- 25901617063
2. Abdul Amin - 25901617064
3. Arghya Sarkar - 25901617061

3. CONTENTS
• What is Li-Fi?
• Why is it required?
• Li-Fi over Wi-Fi
• Working & Laser
• Ideal range for working
• Disadvantages
• Applications
• Ideas for more applications of this technology
• Future scope of Li-Fi data transfer
• Reference

4. Li-Fi, as coined by Prof. Harald Haas during his TED
Global talk, is bidirectional, high speed and fully
networked wireless communications similar to Wi-Fi.
Li-Fi is a subset of optical wireless
communication (OWC) and can be a complement to RF
communication (Wi-Fi or Cellular network), or a
replacement in contexts of data broadcasting.
WHAT IS LI-FI?

5. Existing wireless technology - Why do we
need an alternate technology?
 CAPACITY
 EFFICIENCY
 AVAILABILITY
 SECURITY

6. SOME IMAGES OF LIGHT FIDELITY DATA TRANSFER
LASER
SOLAR PANEL
REFLECTOR MIRROR

7. VISIBLE SPECTRUM

8. LIFI OVER WIFI

9. WORKING

10. CIRCUIT DIAGRAM

11. COMPONENT LIST
1. Laser 3.3-5.5 Volts x3
2. Solar Panel 6 Volts x2
3. Switch 1Amp x2
4. Auxiliary Socket 3.5mm x2
5. Reflector Mirror x1
6. Fiber Stand x3
7. Auxiliary Cable 3.5mm x2
8. Plastic Electric Board x2
9. Battery 9Volts x1
10. PVC Wire 0.5mm x

12. LASER
Lasers are distinguished from other light sources by
their coherence. Spatial coherence is typically
expressed through the output being a narrow beam,
which is diffraction-limited. Laser beams can be
focused to very tiny spots, achieving a very
high irradiance, or they can have very low divergence
in order to concentrate their power at a great
distance.

13. IDEAL RANGE FOR WORKING
In this Li-Fi System, we use Laser which is different
performance in different Distance, Weather, Day, Night
Basis…
In day performance:
Very good performance under 30 feet Distance
Average performance between 30 feet to 50 feet
Poor performance Above 50feet
In night performance:
Very good performance under 50 feet
Average performance between 50 feet to 70 feet
Poor performance Above 70 feet

14. DISADVANTAGES
Nothing in this world is perfect and so does
LIFI.
 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.

15. APPLICATIONS
 Underwater communications: Since radio waves cannot be
used under water because these waves are strongly absorbed by
sea water within feet of their transmission and this renders it
unusable underwater but LIFI is suitable for underwater
communication
 Health sector: Since WIFI is not safe to be used in hospitals and
other various health care sectors because it penetrates human
body. LIFI can be implemented and well suit in this sector.
 Internet anywhere: street lamps, light of vehicles can be used
to access internet anywhere in footpaths, roads, malls, anywhere
where light source is available.
 Safety and management: it can be used to update traffic
information at almost every instant and it will be easy for traffic
police to deal with traffic and catch the one who breaks the rule.

16.  Finding the location of a person :
LiFi uses visible light and this property can be
exploited in finding the location of people. Suppose if a
child is misplaced and he/she is wearing an earing which
is made of Led’s. this led can constantly communicate
with the visible light available and reveal the location of
the child.
 Navigation System : since visible light is present
everywhere, we can create internal navigation systems
for the bigger areas to create automated machinery/
automatic navigation for the visitors.
IDEAS FOR MORE APPLICATIONS

17.  Underwater Applications : the LEDs can be
embedded in the water bed to reveal the various
impurities underwater. The various leds will
communicate with each other to give the overall
amount of impurity in that particular area.
 Instant data transfer between the devices : the
high speed transfer of the leds can be used to
transfer the data between the devices.
 The disadvantage of the Lifi is uplink is difficult.
 So we can have the photodiodes embedded near to the people
on the pillars for eg.
 Or we can have the same led behaving as a photodiode as well
as an led.
IDEAS FOR MORE APPLICATIONS

18. FUTURE SCOPE OF LI-FI DATA
TRANSFER
The advantage of this device is that in addition to their
lightening capabilities, it can be used for data
transmissions as well. In this paper, the authors have
made an exhaustive study on technology of Li-Fi and its
applications in transferring data from one computer to
another computer. The authors have also made study on
advantages as well as disadvantages of using Li-Fi in
transferring data from one computer to another
computer. The massive use of Li-Fi may solve some
bottleneck of data transmission in Wi-Fi technology.

19. REFERENCES
 https://www.ijstr.org/final-print/oct2014/Li-fi-A-
New-Era-Of-Wireless-Communication-Data-
Sharing.pdf
 https://www.youtube.com/watch?v=NaoSp4NpkGg
 https://en.wikipedia.org/wiki/Li-Fi

20. THE END
Thank You…