Marshall ECE-B

1

By

Marshall

ECE

Srinivas College

mangalore

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• PRESENT SCENARIO OF WirelessComunicaion

• ISSSUES WITH RADIO FREQUENCY SPECTRUM

• COMPARING THE EM SPECTRUM

• CONSTUCTION AND WORKING OF LI-FI

• OVERCOMING THE ISSUES

• ADVANTAGES

• LIMITATIONS

• APPLICATIONS

• CONCLUTION

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We have 1.4 million cellular base stations deployed

We also have 5 billion of mobile phones

Mobile phones transmit 600TB of data every month

Presently Wifi uses radio waves for communication

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We transmit wireless data through radio waves.

Radio waves are limited.

Radio waves are scarce and expensive.

We only have certain range of it.

With advent of new technologies like 3G, 4G we

are running out of spectrum.

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COMPARING THE SPECTRUM

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There are 1.4 million cellular radio base stations.

They consume massive amount of energy.

Most of this energy is not used for transmission

but for cooling down the base stations.

Efficiency of such a base station is only 5% and

that rise a big problem.

EFFICIENCY

Availability of radio waves or RF signals causes

another concern.

We have to switch off mobile phones in airplanes.

Radio waves cannot be used under water

It is not advisable to use mobiles at places like

petrochemical plants and petrol pumps, nuclear

power plant etc.

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AVAILABILITY

Radio waves penetrates through walls.

They can be intercepted.

If someone has a knowledge and bad

intentions then he may misuse it.

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SECURITY

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What is Li-Fi / VLC ?

Use of the visible light portion ofthe electromagnetic spectrum for datatransmission.

LED light bulbs are turned into highspeed wireless communication devices,somewhat like a Wi-Fi, hence the nameLi-Fi(VLC=Visible light Communication)

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Construction and working

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1. CAPACITY

10,000 TIMES MORE SPECTRUM THAN

RW.

LIGHT DEVICES ARE ALREADY PRESENT,

SO INFRASTRUCTURE IS AVAILABLE

ALREADY AND INSTALLED.

2. EFFICIENCY

HIGHLY EFFICIENT BECAUSE LED

CONSUMES LESS ENERGY.

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3. AVAILABLITY

LIGHT IS PRESENT EVERYWHERE.

CAN BE USED UNDERWATER ALSO.

4. SECURITY

LIGHT WAVES DOESNOT PENETRATE

THROUGH WALLS.

HENCE THEY CAN’T BE INTERCEPTED.

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WE CAN USE LI-FI IN HOSPITALS AND

AIRCRFTS ALSO.

CHEAPER THEN WIFI , SINCE VISIBLE

LIGHT SPECTRUM IS A FREE SPECTRUM

BAND.

LED CONSUMES LESS ENERGY

THOUSANDS AND MILLIONS OF STREET

LAMPS CAN BE COVERTED TO LI-FI

SPOTS.

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There should be line of sight between sender

and receiver

Visible light cannot penetrate through solid

objects

Interference with other electromagnetic waves

makes the transmitting data to distort

Light cannot approach the range and

penetration of radio waves

High installation cost of the VLC system.

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• AIRLINES

• TRAFFIC LIGHTS

• MEDICAL ASPECTS

• SMART MUSEUMS

• SMARTER POWER PLANTS

• ON OCEAN BED

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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 Wi-Fi

hotspot to transmit wireless data and we will

proceed onwards for a..

Cleaner, Greener, Safer and Brighter future.

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