visible light communication
DESCRIPTION
This technology helps in data transferring through visible lights.TRANSCRIPT
Visible Light communication
By SAGINESH M K
APPLIED ELECTRONICSMPTC VADAKARA
Seminar on
Sustainable Energy-Efficient Wireless Application Using Light
OutlineIntroduction
Motivation
History
Technology and modulation
VLC Characteristics
VLC vs. RF Characteristics
Advantages & Disadvantages
Applications
Conclusion
Introduction
Lighting 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.
VLC History1900s Current405 B.C. 1800s280 B.C. 1880~
FireFire
SunlightSunlight
LampLamp
LEDLED
Heliograph
Beacon
Fire
Pharos
Lighthouse
Ship-to-ship
Comm.
Photophone
By Bell
Traffic Light
/Signboard Light
800 B.C.
Burning KiteIn Battle
VLCVLC
Technology & Modulation
Data Light source
Modulation
(PPM/FSK)
DataDemodulatio
n(PPM/FSK)
PD or CCD
Why WLED ?
Brightness / Power ratio
Cost
/ B
rig
htn
ess r
ati
o
Incandescent Lamp
Halogen Lamp Fluorescent Lamp
LED
LED
LED
LED
2003
2005
2010
2015
50 100 1500
1
10
100
VLC CharacteristicD
ata
rate
(bps)
115K
4M
100M
480M
16M
50MUFIR
FIR
IR
VI
VLC
1 11
3
Distance (m)
2 6 20
50
UWB
802.11a
802.11b
Bluetooth
ZigBee
Transmitter/receiver of VLCVisible light LED
Fluorescent lamp
PIN photo diode
Avalanche photo diode
Image sensors
VLC vs. RF Characteristics
Property VLC RF
Visibility Yes No
Bandwidth Unlimited, 400nm~700nm
Regulatory, BW Limited
EMI No High
Hazard No Yes
Power Consumption
Relative 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
2.Flow planning survey system for a store
Applications (contd)3.Inside airplane communication
4.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.
ReferenceI. http://press-releases.techwhack.com/25210-irdaII. Hirohashi, Ikawa, Lin, “High-Speed Full-Duplex Multi-
access System for LED Based Wireless Communications Using Visible Light ”, International Symposium on Optical Engineering and Photonic Technology: OEPT 2009, July 2009, Orlando,
III. T. Komine and M. Nakagawa, “Fundamental analysis for visible-lightcommunication system using LED lights,” IEEE Trans. Consumer Electron vol. 50
IV. The Case for Vehicular Visible Light Communication (VLC): Architecture, Services and Experiments By Cen Bi Liu
V. Visible Light Communication Chung Ghiu Lee Chosun University South Korea
Questions ?
THANK YOU
Photophone
Heliograph
Image sensors
Image sensors