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Ms. AREEFA BANUINFORMATION SCIENCE AND ENGINNEERINGSRI VENKATESHWARA COLLEGE OF ENGINEERING LI-FI TECHNOLOGYFASTER WAY FOR WIRELESS DATA TRANSMISSIONPRESENTED BY Mr. SHANTOSH RAJINFORMATION SCIENCE AND ENGINEERING SRI VENKATESHWARA COLLEGE OF ENGINEERINGAndUNDER GUIDANCE OFMrs.Pankaja R Assistant professor, Department of CSESri Venkateshwara College Of Engineering

Powerpoint TemplatesPage #IntroductionWhat is Wi-Fi ???Issues regarding Wi-Fi (Radio Spectrum)What is Li-Fi???Principle of Li-Fi TechnologyVisible Light CommunicationConstruction and Working of Li-FiComparison between Wi-Fi and Li-FiFuture Applications of Li-FiAdvantages and DisadvantagesConclusionReferences

CONTENTSPowerpoint TemplatesPage #WHAT IS Wi-Fi??

WHAT IS Wi-Fi ???Powerpoint TemplatesPage #Powerpoint TemplatesPage #WHO CAN REPLACE RADIO WAVES FOR WIRELESS COMMUNICATION?

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LI-FI

Powerpoint TemplatesPage #Li-Fi (Light Fidelity)Li-Fi (Light Fidelity )can be thought of as a light-based Wi-Fi.Technology uses The Visible SpectrumThe term was first used by Harald Haas in hisTED Globaltalk onVisible Light Communication in 2011 In October 2011 a number of companies and industry groups formed the Li-Fi consortium, to promote high-speed optical wireless systems.Researchers at the Heinrich Hertz Institute in Berlin, Germany, have reached data rates of over 500 megabytes per second using a standard white-light LED.

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LI-FI ENVIRONMENTPowerpoint TemplatesPage #PRINCIPLE OF LI-FI TECHNOLOGY

The heart of this technology is a new generation high brightness leds.Visible Light Communication. These leds 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 leds.

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If led is on , then we transmit a digital signal 1,and if the led is off , then we transmit a digital signal 0.

Powerpoint TemplatesPage #VISIBLE LIGHT COMMUNICATION

Li-Fi is a faster and cheaper version of Wi-Fi, which is based on visible light communication (VLC). The visible light communication is a data communication technique using visible light between 400 THz and 800 THz as an optical carrier for data transmission.

Powerpoint TemplatesPage #WHY VLC???

Powerpoint TemplatesPage #Gama rays,X-rays,Ultraviolet rays are harmful for the human body.Infrared rays are also dangerous, due to eye safety regulation, and can only be used with low power.Radio waves are expensive and they are less secure.Hence we are left with only the VISIBLE - LIGHT SPECTRUM which is not harmful for humans .

Powerpoint TemplatesPage #CONSTRUCTION AND WORKING OF Li-Fi

Powerpoint TemplatesPage #CONSTRUCTION and WORKING OF Li-Fi (conti..)

Li-Fi is implemented using white LED light bulbs at downlink transmitter. By fast variations of the current, optical output can be made to vary at extremely high speeds. An overhead lamp fitted with an LED with signal processing technology streams data embedded in its beam at ultra high speeds to the photodiodes. A receiver dongle then converts the tiny changes in amplitude into an electrical signal, which is then converted back into a data stream & transmitted to a computer or mobile device.

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Sl.NoParametersLight Fidelity Wireless Fidelity1Speed for data transferFaster transfer speed (>1 Gbps)Data Transfer speed (150 Mbps)2Medium through whichdata transfers occursUsed Light as a carrierUsed Radio spectrum3Spectrum RangeVisible light spectrum has 10,000 timebroad spectrum in comparison to radio frequencyRadio frequency spectrum range isless than visible light spectrum.4CostCheaper than Wi-Fi because free banddoesnt need license and it use light.Expensive in comparison to Li-Fibecause its uses radio spectrum.5Network topologyPoint to pointPoint to point6Operating frequencyHundreds of Tera Hz (THz)2.4 GHzCOMPARISON BETWEEN LI-FI AND WI-FI

FUTURE APPLICATIONS

In vehicles and traffic lights, reducing accidents and traffic congestion

In Airplanes' And Underwater

Hospitals

Street lamps(as free access points)

Petroleum and chemical industriesADVANTAGESDISADVANTAGES

Light can't pass through objects.

A major challenge facing Li-Fi is how the receiving device will transmit back to transmitter.High installation cost of the VLC systems

Interferences from external light sources like sun , light , normal bulbs , opaque materials .

CONCLUSIONThe possibilities are numerous and can be explored further.

In spite of disadvantages if this technology can be put into practical use, every bulb can be used something like a Wi-Fi hotspot to transmit wireless data and we will proceed toward the cleaner, greener, safer and brighter future.

REFERENCESJyoti Rani1, Prerna Chauhan2, Ritika ripathi3,1Student, ,2Student,ad ,3Assistant Professor, ECE, Dep't. " Li-Fi (Light Fidelity)-The future technology In Wireless communication" ISSN 0973-4562 Vol.7 No.11 (2012)Shailander kaushik, System Analytic,Nuclear Software export Ltd, "An overview of technical aspects for wifi networks technology " ,ISSN-2277-1956.Visible Light Communications Consortium,www.vlcc.net, 2008Sathya.T,Prof.E.Divya,Prof.S.Raja,student,assistant professor, head of department, ECE, CTKEC,"Visible Light Communication for Wireless Data Transmission ". Coimbatore, India Feb. 2014. Harald Haas "Wireless Data From Every Light bulb" TED Global Edinburgh, July 2011.M.Muthamma , Assistant Professor, ECE, GCET, Hyderabad , A.P., India ." A survey on Transmission of data through illumination - Li-Fi " Dec 2013.

Mrs.Pankaja RAssistant Professor , Department of Computer Science and Engineering

For guiding us throughout the preparation of this paper presentationSpecial Thanks to