Visible Light communication

BYG.LAXMANA RAO

IV B.TECH

ECE 11BR1A0436

Vijaya Engineering College DEPARTMENT OF ELECTRONICS &COMMUNICATION

ENGINEERING TECHNICAL SEMINOR ON

UNDER THE GUIDENCE OFPRAVEEN KUMARR

ASSISTANT PROFESSOR

OutlineIntroductionMotivation

Technology and modulation

VLC vs. RF CharacteristicsAdvantages & DisadvantagesApplications

Conclusion

IntroductionLighting is a major source of electric

energy consumption. Visible light communication is a data

communications medium using visible light between 400 THz-800THz.

General characteristics: visibilitySecurityHarmless for human bodyUnregulatedUsing in restricted areaEye safety

MotivationI. Now, researchers came to realize that

WLED devices could also be used for wireless purposes.

II. LEDs rends to be considerable cheaper than RF.

III.Optical wireless allows easy bandwidth reuse and improve security.

IV. It doesn’t generate RF contaminations.

V. Replacing RF device will reduce interference in RF band.

VI.RF radiation in hospital and airplane will be vanished .

VII.Large amount of energy can be saved.

Technology & Modulation

Data Light source

Modulation

(PPM/FSK)

DataDemodulatio

n(PPM/FSK)

PD

Why WLED ?

Brightness / Power ratio

Cost

/ Br

ight

ness

rat

io

Incandescent Lamp

Halogen Lamp Fluorescent Lamp

LED

LED

LED

LED

2003

2005

2010

2015

50 100 1500

1

10

100

VLC CharacteristicDa

ta ra

te (b

ps)

115K

4M

100M

480M

16M

50MUFIR

IRVI

VLC

1 11

3Distance (m)

2 6 20

50

BluetoothZigBee

Transmitter/receiver of VLCVisible light LED

Fluorescent lamp

PIN photo diode

Avalanche photo diode

VLC vs. RF CharacteristicsProperty VLC RFVisibility Yes No

Bandwidth Unlimited, 400nm~700nm

Regulatory, BW Limited

Hazard No YesPower

ConsumptionRelative low Medium

Coverage Distance

Short Medium

Advantages1.Transmit data by sockets of existing

light fixtures.

2.Alleviate a number of problems associated with the radio frequency (RF) communication systems.

3.consume far less energy .

4. Security.

5.Harmless for human body.

6.Eye safety.

Disadvantages1.Atmospheric absorption

2.Shadowing.

3.Beam dispersion

4.Interference from background light sources

Applications1.Under water communication system

Applications (contd)2.Inside airplane communication

3.Vehicle to vehicle messaging

5.Indoor broadcasting system.Applications

(contd)

Conclusion and outlookThere are many application that can

be realized using Visible Light Communication. Careful consideration will be needed to introduce it into a market.

THANK YOU