Lifi presentation

AUROBINDO INSTITUTE OF ENGG & TECH SHERIGUDA,IBRAHIMPATNAM,R.R DIST

PRESENTATION ON

A FASTEST WIRELESS TECHNOLOGY

BY

G.REDDY VENKATESH126Z1A0403

Walk Through……

1.PRESENT SCENARIO2.INTRODUCTION TO LI-FI3.ORIGIN OF LI-FI4.WHY ONLY VLC5.HOW LIFI WORKS6.APPLICATIONS OF LI-FI7.ADVANTAGES OF LI-FI8.LIMITATIONS OF LI-FI9.CONCLUSION

1.Present Scenario1.Present ScenarioDependent on internetDependent on internetSharing of dataSharing of dataInternet speeds quite annoyingInternet speeds quite annoyingWi-Fi uses radio waves from radio Wi-Fi uses radio waves from radio spectrumspectrumFreqency range < 300GHz EM wavesFreqency range < 300GHz EM wavesCongestion of radio spectrumCongestion of radio spectrumYou tubeYou tube

Limitations of wi-fi:

• Getting blocked slowly• Increasing complexity

Are radio waves n’t fine? Four issues 1.Capacity 2.Efficiency3.Security4.Avaliability

2.Introduction to Li-Fi2.Introduction to Li-Fi Replacing Rw with VLCReplacing Rw with VLC

What is the need for LI-FI ?What is the need for LI-FI ? What is Li-Fi ?What is Li-Fi ?

It stands for light fidelityIt stands for light fidelity Optical version of wi-fiOptical version of wi-fi Uses visible light (LED Light) instead of radio wavesUses visible light (LED Light) instead of radio waves Component of IOT Component of IOT

How does it defer?• Privides illumination as well as data transmission• Based on led for transfer of data• Speed is incredibly high

Origin of Li-Fi Technology began during

1990’s Lifi came out from mind of

Dr.Haas he calls it “data through illumination

He coined the term Lifi in 2011 at TED Global talk

The research was initiated by consortium of universities

Dovelopment of LEDs is the biggest accomplishment

Is this proven technology ? Lifi is verified experimentally Prof Haas demonstrated at

global talk on 12th july 2011 by transmission of video data @ 10MBps later he achieve 123MBps

Why only VLC ?Why only VLC ? VLC uses direct modulation and demodulationVLC uses direct modulation and demodulation Radio technology is complexity Radio technology is complexity It is a data communication medium, which uses visible light It is a data communication medium, which uses visible light

frequency range between 400THz(780nm)-800THz(375um)frequency range between 400THz(780nm)-800THz(375um)

EM SpectrumEM Spectrum

Construction of VLC systemConstruction of VLC system

Lifi product consists of 4 Lifi product consists of 4 primary sub assembles primary sub assembles

1.1. White LED Bulb White LED Bulb (source of light)(source of light)

2.2. Radio freq power Radio freq power amplifier circuit amplifier circuit

3.3. Printed circuit board Printed circuit board 4.4. EnclosureEnclosure

How does Lifi work ?How does Lifi work ?Working Principle of Lifi :Working Principle of Lifi : By varying the current through the LED at high speed By varying the current through the LED at high speed

we can vary the output at very high speeds we can vary the output at very high speeds It uses visible light for data communication It uses visible light for data communication For Ex : Imagine a Torch (Due to rapidity of motion of For Ex : Imagine a Torch (Due to rapidity of motion of

switching between on & off states torch appears to be switching between on & off states torch appears to be on constantly)on constantly)

We should be able to see the light but we can’t see We should be able to see the light but we can’t see the datathe data

LEDs permitting us to send required data via lightLEDs permitting us to send required data via lightDescription of working process :Description of working process : Constant currentConstant current is applied across the LEDs to use is applied across the LEDs to use The light is detected by photo sensitive devicesThe light is detected by photo sensitive devices Light is amplified & processed then fed to deviceLight is amplified & processed then fed to device LEDs varies in intensity so fast ; human can’t detect it LEDs varies in intensity so fast ; human can’t detect it

WORKING-->WORKING-->

Continue…….Continue…….

• if LED is on=transmit 1if LED is on=transmit 1 off=transmit 0off=transmit 0• Some LEDs & a controller is needed which can code data into those Some LEDs & a controller is needed which can code data into those

LEDs in order to setup the systemLEDs in order to setup the system• By varying the rate(flickering) we encode the desired dataBy varying the rate(flickering) we encode the desired data

Modulation techniques used in Lifi:Modulation techniques used in Lifi:Lifi uses VL for sending data,for transmission modulation of the data Lifi uses VL for sending data,for transmission modulation of the data

necessarynecessary1.1. OFDM(orthoganal freq-division multiplexing)OFDM(orthoganal freq-division multiplexing)2.2. OOK(on-off keying)OOK(on-off keying)3.3. PWM(pulse width modulation)PWM(pulse width modulation)4.4. PPM(pulse position modulation)PPM(pulse position modulation)5.5. SIM-OFDM(Sub carrier index modulation OFDM)SIM-OFDM(Sub carrier index modulation OFDM)6.6. Use of OLEDs(orthogonal light emitted diodes)Use of OLEDs(orthogonal light emitted diodes)

Applications of Li-fiApplications of Li-fi

Lifi finds a varity of applications in many fields from access to internet .it Lifi finds a varity of applications in many fields from access to internet .it can easily be used in all such places where blutooth,infrared,wifi & can easily be used in all such places where blutooth,infrared,wifi & Internet are broadly in use. Some of applications represented below.Internet are broadly in use. Some of applications represented below.

1.1. Education systemEducation system2.2. Internet access in aircraftsInternet access in aircrafts3.3. Traffic lightsTraffic lights4.4. Intrinsically safe environmentIntrinsically safe environment5.5. On ocean bedsOn ocean beds6.6. In the field of medicineIn the field of medicine

Continue…..Continue…..

Advantages Advantages Cheaper than wifi,since visible Cheaper than wifi,since visible

light spectrum is free bindlight spectrum is free bind No license neededNo license needed It supports broadcasting of It supports broadcasting of

networknetwork Mobile connectivityMobile connectivity Issues of shortage of radio freq Issues of shortage of radio freq

bandwidth may be sorted outbandwidth may be sorted out

It gives solutions to problems in It gives solutions to problems in wi-fi:wi-fi:

CapacityCapacity EfficiencyEfficiency AvailabilityAvailability SecuritySecurity ConnectivityConnectivity

Limitations of lifiLimitations of lifi

Light waves can be easily Light waves can be easily blocked blocked

Light can’t pass through solid Light can’t pass through solid objects such as walls & objects such as walls & obstaclesobstacles

Li-fi requres line of sightLi-fi requres line of sight Presence of light is essentialPresence of light is essential Light can’t approach the range Light can’t approach the range

of radio wavesof radio waves Interference from external Interference from external

sources of light in path of sources of light in path of transmission will cause transmission will cause interruption in communicationinterruption in communication

ConclusionConclusion

Future scope:Future scope: We ulitimately run out of radio spectrumWe ulitimately run out of radio spectrum Li-fi can be used in each and every scenario without worry Li-fi can be used in each and every scenario without worry

of spectrum shortageof spectrum shortage Li-fi can become one of the major technologies in near futureLi-fi can become one of the major technologies in near future The future of li-fi is Gi-fi or giga bit wireless communicationThe future of li-fi is Gi-fi or giga bit wireless communication

Any quarries…Any quarries…Any

quarries….