1. LiFi
LiFi stands for Light fidelity
Group members :-
• Chetan kadam (co-4G)
• Suyog malkar (co-4G)
• Riddhesh bhoir (co-4G)
2. Contents:-
• What is LiFi…?
• History of LiFi
• Working of LiFi
• Difference between LiFi & Wi-Fi
• Construction of LiFi
• Application of LiFi
• Conclusion
3. What is LiFi….?
• Light Fidelity or Li-Fi is a Visible Light Communications (VLC) system
running wireless communications travelling at very high speeds.
• Li-Fi uses common household LED (light emitting diodes) lightbulbs to
enable data transfer, boasting speeds of up to 224 gigabits per second.
• The term Li-Fi was coined by University of Edinburgh Professor Harald
Haas during a TED Talk in 2011. Haas envisioned light bulbs that could
act as wireless routers.
4. History of LiFi
• Harald 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 LiFi.
• 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.
• 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 colour LED. In September 2013, a press
release said that Li-Fi, or VLC systems in general, do not require line-of-sight
conditions. In October 2013, it was reported Chinese manufacturers were working on
Li-Fi development kits.
5. Working of LiFi
• Li-Fi and Wi-Fi are quite similar as both transmit data electromagnetically. However, Wi-Fi
uses radio waves while Li-Fi runs on visible light.
• As we now know, Li-Fi is a Visible Light Communications (VLC) system. This means that it
accommodates a photo-detector to receive light signals and a signal processing element to
convert the data into 'stream-able' content.
• An LED lightbulb is a semi-conductor light source meaning that the constant current of
electricity supplied to an LED lightbulb can be dipped and dimmed, up and down at extremely
high speeds, without being visible to the human eye.
6.
7. Feature LiFi Wi-Fi
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 not have any interference issues
similar to radio frequency waves.
Will have intereference issues from
nearby access points(routers)
Technology Present IrDA compliant devices
WLAN 802.11a/b/g/n/ac/ad standard
compliant devices
Applications
Used in airlines, undersea explorations,
operation theatre in the hospitals, office
and home premises for data transfer
and internet browsing
Used for internet browsing with the
help of Wi-Fi kiosks or Wi-Fi hotspots
Merits(advantages)
Interference is less, can pass through
salty sea water, works in densy region
Interference is more, can not pass
through sea water, works in less densy
region
Difference between LiFi & Wi-Fi
9. Application of LiFi
1. Security:-
In contrast to radio frequency waves used by Wi-Fi, lights cannot penetrate through walls and
doors. In a meeting or living room condition, with some prevention on transparent materials, like
curtains on window, the access of a Li-Fi channel is constrained in that room.
Underwater Application:-
Most remotely underwater operated vehicles (ROVs) use cables to transmit command, but the
length of cables then limits the area ROVs can detect. However, as light wave could travel through
water, Li-Fi could be implemented on vehicles to receive and send back signals.
1. Hospital :-
Many treatments now involve multiple individuals, Li-Fi system could be a better system to
transmit communication about the information of patients. Besides providing a higher speed,
light waves also have little effect on medical instruments and human bodies.
Vehicles :-
Vehicles could communicate with one another via front and back lights to increase road safety.
Also street lamps and traffic signals could also provide information about current road situations.
10.
11. Conclusion of LiFi
• Li-Fi is a new form of technology, and has not even been deployed to
the masses
• Reports say that the growth will be elevated to 83% by the year 2018.
• Soon, Li-Fi will be replaced by Wi-Fi.
