NIKET CHANDRAWANSHIBranch – Computer science & engineering

4th semesterRoll no. – 0177cs101041

College – IES college of Technology

RECENT ADVANCE TECHNOLOGIESIN

COMMUNICATION

V L C

IT IS NOT A VIDEO LAN

That crashes our laptop, desktop Speakers…..

V L C VISIBLE LIGHT

COMMUNICATION

The technology was originally developed by the D-Light project at the University of Edinburgh and has been exclusively licensed to PureVLC.  This

technology allows standard LED light bulbs to be turned into high speed wireless communications devices, a bit like a Wi-Fi, hence the name Li-Fi

which is often used.

ABSTRACT..

VisibleLight Communication uses light emitting diodes

(LEDs), forthe dual role of illumination and data transmission.

Using thevisible light spectrum, which is free and less crowded

thanother frequencies, wireless services can be piggy-

backed overexisting lighting installations. With this leading edge

technology,data including video and audio, internet traffic, etc,

can betransmitted at high speeds using LED light. In

addition, wheresecurity of local communication is important eg

defense andfinance applications, D-Light technology offer a

secure mediumfor communication in an office/building environment

THE CERTAIN CHANGES IN AMPLITUDE OF LIGHT IN PHOTO DETECTOR HELP TO CONVERT THE LIGHT INTO THE ELECTRICAL SIGNALS

A significant attribute of LEDs is their ability to switch on and

off thousands of times per second. No other lighting technology

has this capability. This switching occurs at ultra-high speeds,

so far beyond what the human eye can detect, that the light

appears to be constantly on. Amazingly, the technology can

transmit a signal even when the light appears off. These

embedded signals are emitted from the LEDs in the form of

binary code; 'off' equals zero and 'on' equals one. When LVX

equipment and devices are placed throughout a building of

geographical area, a comprehensive wireless communicationnetwork can be created.

What is VLC ?

LARGE AMOUNT OF DATA IS TRANSFER THROUGH A NETWORK

LED

’sCO

MPU

TER

HOW IT WORKS…

INTRODUCTION….Visible Light Communication System

Visible Light Communication system are presently beingdeveloped by scientists seeking to create ultra high-

speed,high security, biologically friendly communications

networksthat allow the creation and expansion of seamless

computingapplications using very large bandwidth high-frequency

pulsedlight instead of radio waves and microwaves.

Such systems use modulated light wavelengths emitted (and

received) by a variety of suitably adapted standard sources,

such as indoor and outdoor lighting, displays, illuminated signs,

televisions, computer screens, digital cameras and digital

cameras on mobile phones for communication purposes,primarily through the use of white Light Emitting Diodes

(LEDs).

INTERFERENCE-FREE REUSE IN VLC ENABLES HIGH DATA RATES PER

UNIT AREA

WHY SHOULD WE NEED VLC/LI-FI… Radio spectrum is congested but

the demand for wireless data doubles each year.  Everything, it

seems, wants to use wireless data but the capacity is drying up.  Wireless radio frequencies are getting higher, complexities are growing and RF interference

continues to grow.

WHY SHOULD WE NEED VLC/LI-FI The solution is Li-Fi. Direct

modulation of LED devices is a low cost, secure, and safe way to transmit data, and there is an abundance of free visible light

spectrum.  High intensity LEDs used in light bulbs, flash lights and

cameras can transmit very high data rates, faster than Wi-Fi!

BRIEF DESCRIPTION OF V L C/LI-FI…

It is two way communications that uses medium of light.

It uses photons as medium which carries signals.

It is a safe technology to transfer confidential matters.

Fluorescent light transmits a meaningful amount of data by frequently flickering.

Bandwidth is not limited. Transmitters and receivers devices are

cheap, and there is no need for expensive RF units.

DESCRIPTION (CONTINUE….) LEDs are those which consist of ultraviolet

LED surrounded by phosphorous which is then illuminated by actual LEDs and emits white light.

As a new idea three distinct LEDs are used which are red, green and blue lights at same time and appears as white in human eyes.

Photo diodes are used as receivers which can turns light into electrical signals

Every source of lights can be used as transmitter in VLC

DESCRIPTION (CONTINUE….) Signals in this form can then converted into

actual data Even the VLC technology is simple; it has

many difficulties in practical application The preferred light sources are fluorescent

lights and LEDs. More important requirement is that the light

source has to meet the ability to switch on and off again in a short period of time that is how data is later modulated (LEDs fulfills the requirement of frequent switching on and off)

LIMITATIONS… There should be a line of sight between

sender and receiver, because visible light cannot penetrate into solid objects.

VLC mostly used indoors. Even the VLC technology is simple; it

has many difficulties in practical application.

Also interference with other electromagnetic waves makes the transmitting data to distort.

USES… WiFi Spectrum Relief - Providing additional bandwidth in environments

where licensed and/or unlicensed communication bands are congested Smart Home Network – Enabling smart domestic/industrial lighting;

home wireless communication including media streaming and internet access

Commercial Aviation – Enabling wireless data communications such as in-flight entertainment and personal communications

Hazardous Environments- Enabling data communications in environments where RF is potentially dangerous, such as oil & gas, petrochemicals and mining

Hospital and Healthcare – Enabling mobility and data communications in hospitals

Defence and Military Applications – Enabling high data rate wireless communication within military vehicles and aircraft

Corporate and Organisational Security – Enabling the use of wireless networks in applications where (WiFi) presents a security risk

Underwater Communications – Enabling communications between divers and/or remote operated vehicles

Location-Based Services – Enabling navigation and tracking inside buildings.

HOW IT WORKS…

HOW IT WORKS…

HOW IT WORKS…

HOW IT WORKS…

HOW IT WORKS…

The need for faster data transmission rates has never been greater. Now a team of scientists at Germany's Karlsruhe

Institute of Technology (KIT) are claiming a world record in data transmission with the successful encoding of data at a rate of 26 terabits per second on a single laser beam and transmitting it over a distance of 50 km (31 miles). The

scientists claim this is the largest data volume ever transported on a laser beam and enables the transmission of

700 DVD's worth of content in just one second

Professor Jurg Leuthold led an experiment that achieved a data transmission rate of

26 terabits per second

SPEED VARIATION ACC. TO TECHNOLOGY..TECHNOLOGY SPEED DATA DENSITY

WIRED FIRE WIRE 800 Mbps *****USB3.0 5 Gbps *****THUNDERBOLT 2X 10 Gbps *****

WIRELESS (CURRENT)WI-FI-IEEE (802.11N) 150 Mbps *BLUETOOTH 3 Mbps *IrDA 4 Mbps ***

WIRELESS (FUTURE)Wi-Gig 2 Gbps **Giga-IR 1 Gbps ***Li-Fi >10 Gbps ****

DIFFERENCE B/W WI-FI AND LI-FI (VLC)

HEAR THE HARLD HASS “CHAIRMAN OF MOBILE COMMUNICATION”

CONCLUSIONVLC based on white LEDs appears to be an important

potentialcomponent in expanding useable bandwidth, protectingsensitive electrical equipment and data, creating more

biologically friendly communications technology, and helpingdevelop seamless computing applications.

VLC offers the advantage of a communications channel in anunregulated, unlicensed part of the electromagnetic

spectrum.In applications where a visible beam is desirable for security itcan provide high data rates. There are a number of technicaland regulatory challenges to be overcome; rapid technical

progress is being made, but the challenges of standardization will require cooperation and agreement from a number ofdifferent bodies. However, success should bring a low-cost

highdata-rate infrastructure that can increase wireless capacity

substantially.