A TECHNICAL SEMINAR ON

PRESENTED BY

P.SRAVYA

(12R91A0280)

TEEGELA KRISHNA REDDY ENGINEERING COLLEGE

EEE HODP.KRISHNA

TECHNICAL SEMINAR COORDINATORS Mr.A.NAGA SRIDHAR (Assoc.Prof) Mr.B.RAMESH (Asst.Prof)

AbstractIntroduction history working technology present scenario Li-Fi vs Wi-Fi Applications Challenges for Li-Fi Conclusion

CONTENTS:-

At the time of using wireless internet at any place whether it is own or stealing from others, one has probably gotten frustrated because of the slow speed of internet when more devices are connected to a single router. Due to increasing of internet users exponentially, Radio Spectrum is congested but the demand for wireless data double each year. Dr. Harald Haas has come up with a solution for those he calls “Data through illumination”.

ABSTRACT

What is Li-Fi ?

Light-FidelityLI-FI is transmission of data through illumination, sending data through a LED light bulb that varies intensity faster than human eye can follow.

INTRODUCTION:-

The technology truly began during the 1990's in countries like Germany, Korea, and Japan where they discovered LED's could be retrofitted to send information.  Harald Haas continues to wow the world with the potential to use light for communication .

HISTORY

Prof. Harald HaasUniversity of Edinburgh

WORKING TECHNOLOGY

LI-FI is implemented using white LED light bulbs which used for illumination by applying a constant current. However, by fast variations of the current, the light output can be made to vary at extremely high speeds. If the LED is on, it transmits a digital 1otherwise it transmits a digital 0. The LEDs can be switched on and off quickly to transmit the data that can’t be detected by a human eye .

LI-FI

Radio Spectrum is congested but the demand for wireless data double each year .Every thing, it seems want to use wireless data but the capacity is drying up.

PRESENT SCENARIO:-

1.4 Million Base Stations 5 Billion

APPLICATIONS:- Li Fi technology is still in its infancy .However some areas where it seems perfectly applicable are:-

POTENTIAL APPLICATION OF LI-FI

1 . Traffic Lights :-

Traffic lights can communicate to the car and with each other. Cars have LED-based headlights, LED-based cack lights, and cars can communicate with each other and prevent accidents in by exchanging information.

2. Hospitals(In Few Medical Equipment’s):-

3. Airlines :-

Whenever we travel through airways we face the problem in communication media ,because the whole airways communication are performed on the basis of radio waves. To overcome this drawback on radio ways , li-fi is introduced.

4. On Ocean Beds :-

Li-Fi can even wok underwater were Wi-Fi fails completely, thereby throwing open endless opportunities for military/navigation operations

CHALLANGES:-

1. Light can't pass through objects .

2. Interferences from external light sources like sun light, normal bulbs, and opaque materials in the path of transmission will cause interruption in the communication.

3 .Li-Fi requires line of sight.

4. High installation cost of the VLC systems

5. A major challenge facing Li-Fi is how the receiving device will transmit back to transmitter.

CONCLUSION:-

The possibilities are numerous and can be explored further. If this technology can be put into practical use , every bulb can be used something like a Wi-Fi hotspots to transmit wireless data.

ANY QUERIES!