Li-Fi(Light Fidelity)

Presentation on Li-Fi (Light Fidelity)

Present bySubhrangsu Sekhar Dey

Contents Introduction History Working process Applications Advantages Disadvantages Conclusion

Present Wireless Communication demands..

IN Radio spectrum/wireless communication 1.4 Million base stations, 5 billion

Mobile stations 600Tb data every day

Issues regarding Radiospectrum

Capacity

Radiowaves Cost and Expensive Less Bandwidth compared to other spectrums

Insufficient spectrum for increasing data

Efficiency1.Millions of base stations consume huge amount of energy. 2.limited efficiency.3. Maintainance of base stations.(dec.efficiency)

Availability Available within the range of Base stations

Limited availabity Unavailable in aircraftsSecurity: Less secure(passes through the walls)

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WHO CAN REPLACERADIO WAVES

COMMUNICATION TO TO ACHIEVE THE

SAME AT LOW COST?

WHAT IS LI – FI ?

LI-FI is transmission of data through a LED light bulb that varies intensity faster than human eye can follow

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

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on 12th July 2011. He used a table lamp with an LED bulb to transmit a video of blooming flowers that was then projected onto a screen behind him. During the event he periodically blocked the light from lamp to prove that the lamp was indeed the source of incoming data.

then, Haas demonstrated a data rate of transmission of around 10Mbps -- comparable to a fairly good UK broadband connection. Two months later he achieved 123Mbps.

Back in 2011 German scientists succeeded in creating an800Mbps (Megabits per second) capable wireless network by using nothing more than normal red, blue, green and yellow light spectrum..

How LI-FI Works ?Operational procedure is very simple,if the LED is on, you transmit a digit ‘1’,or data is transmittedif it is off you transmit a ‘0’ and data is not transmitted

The LEDs can be switched on and off very quickly, which gives nice opportunities for transmitting data.

Hence all that required is some LEDS and acontroller that code data into those LEDs.

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Radio Waves

Infrared

RaysVisible Rays

Ultraviolet Rays

X- Rays

Gama Rays

WHY ONLY VLC

Gama rays.X-rays.Ultraviolet lightInfraredRadio waves

HENCE WE LEFT WITH THE ONLY THE VISIBLE - LIGHT SPECTRUM.

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data showerFor higer-speed technologies, the Li-Fi Consortium defined data Shower with diagram

APPLICATIONs OF LI-FILi Fi technology is still in its infancy .However some areas where it seems perfectly applicable are:-

TRAFFIC LIGHTS Traffic lights can communicate to the car and with each other.

Cars having LED-based headlights, LED-based back lights, cars can communicate with each other and prevent accidents by exchanging information.

INTRINSICALLY SAFE ENVIRONMENTS

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

PUBLIC INTERNET HOTSPOTS There are millions of street lamps deployed around the world.

Each of these street lamps could be a free access point.

APPLICATIONs OF LI-FI

ON OCEAN BEDS

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

APPLICATIONs OF LI-FI

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3- AirlinesWhenever 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 radioways , li-fi is introduced.

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Advantages It is possible to achieve more than 10Gbps, theoretically allowing a high definition film to be downloaded in 30 sec.

Mostly powered by LEDs, so it is cost efficient.

Transmission of data is fast and easy. Led also more safe than CFL(Toxic “Mercury” present) It’s main advantage is it’s bandwidth. It is 10,000 times than the radio waves

Disadvantages

1.Presence of light is essential.2.Works better with fluorescent light and LEDs but very low efficiency with bulbs3.Light can not panetrate walls4.Interference may be done by other light source like normBulbs4.Hight cost on VLC system installations

CONCLUSIONThe 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.

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ANY QUERIES……..

THANK YOU