Li - Fi

A SEMINAR ON:LI-FI

LIGHT FIDELITY

Submitted by:

Sanjana Gupta

4GW11EC057

GSSS INSTITUTE OF ENGINEERING & TECHNOLOGY FOR WOMEN

Mysuru– 570016

DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING

2014 – 2015

VISVESVARAYA TECHNOLOGICAL UNIVERSITYBELAGAVI, KARNATAKA-570018

Under the Guidance of:

Mrs. Manjula GAssociate professor,

Dept. of ECE,GSSSIETW

INTRODUCTION TO LI-FI

•LI-FI IS A TECHNOLOGY THAT USES THE LIGHT EMITTING DIODES TO TRANSMIT THE DATA WIRELESSLY.

•LI-FI IS FAST AND CHEAP OPTICAL VERSION OF WI-FI ,BASED ON VISIBLE LIGHT COMMUNICATION(VLC).

•VLC IS A DATA COMMUNICATION MEDIUM,WHICH USES THE VISIBLE LIGHT BETWEEN 400 THz (780 nm) and 800 THz (375 nm) AS OPTICAL CARRIER FOR DATA TRANSMISSION

Li-Fi can be thought of as a light-based Wi-Fi. That is, it uses light instead of radio waves to transmit information. And instead of Wi-Fi modems, Li-Fi would use transceiver-fitted LED lamps that can light a room as well as transmit and receive information.

Genesis of LI-FIWHO INVENTED IT ?

This technology was invented by German PHYSICIST HARALD HAAS , from the UNIVERSITY OF EDINBURGH ,U.K , who began his research in the field in 2004, gave a debut demonstration of what he called a Li-Fi prototype at the TED Global conference in Edinburgh on 12th July 2011.

PRESENT SCENARIO

1.4 Million 5 Billion

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.

CAN IT BE INFRARED WAVES ? NOIR WAVES ARE HARMFUL FOR OUR EYES HENCE USED AT VERY LOW POWER CAN IT BE UV RAYS? NOUV RAYS ARE HARMFUL FOR OUR SKIN AND CANNOT BE USED FOR LONG DURATION.

CAN IT BE GAMMA RAYS ? NOGAMMA RAYS ARE RADIOACTIVE AND ARE DANGEROUS.

CAN IT BE X-RAY S ? NO

SO WE ARE LEFT ONLY WITH VISIBLE LIGHT SPECTRUM.

HOW DOES LI-FI WORKS?

•THE HEART OF THIS TECHNOLOGY IS A NEW GENERATION HIGH BRIGHTNESS LED’S.

•THESE LED’S VARIES IN INTENSITY (THAT IS GETS ON AND OFF) SO FAST THAT A HUMAN EYE CANNOT DETECT IT.

•IF LED IS ON , THEN WE TRANSMIT A DIGITAL SIGNAL 1,AND IF THE LED IS OFF , THEN WE TRANSMIT A DIGITAL SIGNAL 0.

•A CONTROLLER IS CONNECTED AT THE BACK SIDE OF THESE LED BULBS TO CODE DATA TO THESE LED’S.

LI FI CONSTRUCTION

The LI FI product consists of 4 primary sub-assemblies:• Bulb• RF power amplifier circuit (PA)• Printed circuit board (PCB)• Enclosure3-The PCB controls the electrical inputs and outputs of the lamp and houses the microcontroller used to manage different lamp functions.2- An RF (radio-frequency) signal is generated by the solid-state PA and is guided into an electric field about the bulb. The high concentration of energy in the electric field vaporizes the contents of the bulb to a plasma state at the bulb’s center; this controlled plasma generates an intense source of light. All of these subassemblies are contained in an aluminum enclosure.

In bulb assembly a sealed bulb is embedded in a dielectric material, it is used as an electric field concentrator that focuses energy in the bulb. The energy from E.F rapidly heats the

material in the bulb to a plasma state that emits light of high intensity and full

Spectrum

LIFI VS WIFI

Limitations 0r challenges-

# light can't pass through objects

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

#High installation cost of the VLC systems.

POTENTIAL APPLICATION OF LI-FI

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

1. It will reduce your electricity bill and maintenance bill

2-INTRINSICALLY SAFE ENVIRONMENT

Visible Light is more safe than RF, hence it can be used in places where RF can't be used such as petrochemical plants .

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 overcomes this drawback on radio ways , li-fi is introduced.

4- 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.

5- PUBLIC INTERNET HOTSPOTS

There are millions of street lamps deployed around the world.Each of these street lamps could be a free access point.

6 – IN HOSPITALS

7- ON OCEAN BEDS

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

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.

REFERENCES

1. http://en.wikipedia.org/wiki/Li - Fi 2. www.lificonsortium.org/ 3. Jyoti Rani, Prerna Chauhan, Ritika Tripathi, “Li - Fi (Light Fidelity)-The

future technology In Wireless communication”, International Journal of Applied Engineering Research, vol. 7 No.11, 2012,ISSN 0973-4562.

4. Birender Singh Rawat, Brijesh Aggarwal, Dishant Passi, " LI - FI: A New Era Of Wireless Communication Data Sharing", International Journal of Scientific & Technology Research, issue 10, October 2014, ISSN 2277-8616

5. Dhakane Vikas Nivrutti, Ravi Ramchandra Nimbalkar," Light-Fidelity: A Reconnaissance of Future Technology ",International Journal of Advanced Research in Computer Science and Software Engineering ,ijarcsse, Issue 11, November 2013, Volume 3, ISSN: 2277 128X

6. Akshata M Sonnad, Anjana Gopan, Sailakshmi N R, Divya S, Ambika R, " Recent advancements in Li - Fi technology", International Journal of Electrical, Electronics and Data Communication, Issue-10, Dec-2013, ISSN: 2320-2084 Volume-1

7. Rahul R. Sharma1, Raunak2, Akshay Sanganal ,"Li - Fi Technology-Transmission of data through light",IJCTA, Vol 5 (1),150-154, ISSN:2229-6093

THANK YOU ..