Li-Fi

1. Li-Fi
PRESENTED BY:
SACHIN GUPTA
A Seminar Presentation
DEPARTMENT OFCOMPUTER SCIENCE AND ENGINEERING
NATIONAL INSTITUTE OF TECHNOLOGY, PATNA

2. Contents
 Introduction
 Working
 Why only VLC?
 Benefits
 Limitations
 Comparison with RF communication
 Applications
 References

3. Li-Fi
 Wireless communication technique
 Similar to Wi-Fi
 Light based data transfer using LED
 Uses visible light communication (VLC)
 Speeds of up to 100Gbps

4. Li-Fi Working
Cloud
Router
Server
LED lamp
Photodetector
Signal
processing
Device

5. Why only VLC?
 Gamma-rays,x-rays – Harmful
 UV- dangerous for humans
 IR – bad for eyes

6. Advantages
10000 times more spectrum
No interference
High energy efficiency
High security

7. Limitations
 Cannot penetrate walls
 Less reliability

8. Li-Fi vs Wireless (RF)
Parameter Li-Fi Wireless (RF)
Speed 10Gbps 150Mbps
Medium Visible Light Radio Waves
Spectrum Range 4 – 7.9 x 10
14
Hz 0- 40 GHz
Cost Cheaper Expensive
Security High Low
Efficiency High Low
Interference Opaque obstacles Electromagnetic

9. Applications

10. Applications
 Traffic Lights
 ROV (Remotely Operated Underwater Vehicle)
 Li-Fi hotspot

11. References
 Tsonev, Dobroslav; Videv, Stefan; Haas, Harald (December 18,
2013). "Light fidelity (Li-Fi): towards all-optical networking". Proc.
SPIE (Broadband Access Communication Technologies VIII) 9007
 TED talk :
 Harald Haas. "Harald Haas: Wireless data from every light bulb"