Li-fi technology how it can meet the data demand and various views on it.

1. Light
Fidelity
The Future of Internet…..
- Yogesh Singh

2. Li-Fi

3. Li-Fi
 Light based Wi-Fi.
 Uses Transciever fitted Led’s instead of
modems used in Wi-Fi.
 Transmission of data through illumination.

4. Discovery
 Research work started in 1990’s in countries like
Japan , Russia and Korea.
 In 2011, Harald Hass demonstrated a data
transmission rate of 10 mbps(comparable to a
fairly good UK broadband connection) at
TEDGlobal and later achieved speed of 123
mbps.
 German scientist achieved speed of 800 mbps
using nothing but blue ,red , yellow and green
led’s.

5. Need For Li-Fi
1.4 billion 5 billion
• Radio Spectrum
Congestion
• Issues
• Speed

6. Overcoming Wi-Fi Issues
 Capacity-Spectrum is 10,000 times stronger
than radio-waves.
 Efficiency-Highly efficient as LED consumes
lesser power
 Availability-Light waves available
everywhere.
 Security-Cannot penetrate through walls ,
hence data cannot be penetrated.

7.  Operational procedure is simple!
 If LED is ‘ON’ digital data ‘1’ is transmitted
& if LED is ‘OFF’ digital data ‘0’ is
transmitted.
 Controller connected at backside of led is
used to code the data.
 It is also known as 5G optical
communication.

8. Implementation
• All data from internet is
streamed into lamp driver.
• Data decides how much the
intensity of LED is to be
varied.
• By fast & subtle variation of
current optical o/p will vary
at high speeds.
• Photodetector picks up the
signal.
• Receiver dongle converts
light into data streams.

9. VS
Characteristics Wi-Fi Li-Fi
Standard IEEE 802.11 IEEE 802.15
Range 100 m Based on LED
light
Cost Medium High
Data transfer
rate
800 kbps-11
mbps
> 1Gbps
Power
consumption
Medium Low
Security Medium High

10. Applications
 Traffic
 Lectures
 Industries
 Aircrafts

11. Traffic
• Li-Fi can be used to communicate
with the LED lights of cars.
• Cars have LED based headlights,
backlights and can communicate
with each other.
• This might prevent accidents by
exchange of information when the
vehicles are too close.
• Using Li-Fi, Street lights can be
used to send information about
the road condition to the car.

12. Lectures/Seminar Halls
• Download notes from blogs of
teacher.
• Interactive classrooms with
interconnected devices.
• Sharing of views & queries with entire
class.

13. Industries
Used in RF restricted
environments such as
chemical industries, nuclear
power plants, petrol pumps.

14. Aircrafts
• Whole airways communication is
done using radio-waves.
• Hence passengers face the
problem in communication.
• This problem can be overcome
using Li-Fi, since light waves will
not interfere with radio waves.

15. Advantages
 Data rate greater than 10 Gbps; theoretically
allowing HD movie download in 30 seconds.
 Can be used in RF restricted areas.
 Cost efficient as LED’s consume less power.
 Secured communication.
 Quick and reliable.

16. Limitations
 Visible light cannot penetrate through solid
objects.
 Interference by external light rays can cause
interruptions.
 Data transmission can be easily blocked by
any object placed in front if the LED.
 A major challenge of Li-Fi is how the receiving
device will transmit back to the transmitter.

17. Conclusion
Thus, if Li-Fi is put into practical use, every
bulb can be used as an alternative to Wi-Fi
hotspots. It provides simple, faster and
efficient wireless data communication. Li-Fi
will make us proceed towards the cleaner,
safer, greener and brighter future.