Li-Fi Technology ppt/Mr.S.Satheesbabu.pdf · Introduction LiFi is a wireless optical networking technology that uses light-emitting diodes (LEDs) for data transmission. LiFi is designed

Li-Fi TechnologyPresenter:

Mr. S. Sathees BabuAssociate Professor

CSE departmentPSNACET,Dindigul

Internet of Things

Fitn

ess

Personal Connected Devices

Smart phones

Computers

Televisions

Vehicles

Appliances

Gaming Consoles

Health Monitors

Internet of Things

Content Collection Distribution

Storage Cloud Storage Public / Private Networks

Hacking Privacy Security

BIG DATA

Issues Regarding Radio Spectrum

Capacity Availability

Efficiency Security

Server Internet

Streaming Content

Solid State Lamp

Computer

Internet through a light bulb● Data transmission through illumination● Sending data through a LED light bulb ● Visible electromagnetic spectrum with higher bandwidth than Wi-Fi ● Line of sight limitation● Cheaper and more energy-efficient than wireless radio systems

History• Professor Harald Haas, from the University of Edinburgh

in the UK, is widely recognized as the original founder ofLi-Fi.

• He coined the term Li-Fi and is Chair of MobileCommunications at the University of Edinburgh and co-founder of pureLiFi.

• Haas promoted this technology in his 2011 TED Globaltalk and helped start a company to market it.

• In October 2011, companies and industry groups formedthe Li-Fi Consortium, to promote high-speed opticalwireless systems.

• The first Li-Fi smartphone prototype was presented atthe Consumer Electronics Show in Las Vegas fromJanuary 7–10 in 2014.

Prof. Harald Haas

Disadvantages Of Other Spectrums

Insufficient spectrum for increasing data

Low power application

Which is not used so far.

Dangerous for human body

Used for hospitals

It is not used generally

Radio -Waves

Infra -Red Visible Ultra -

Violet X - rays Gamma -rays

Electromagnetic Spectrum

LiFi is a wireless optical networking technology that uses Visible light for data transmission in Electromagnetic Spectrum

Introduction LiFi is a wireless optical networking technology thatuses light-emitting diodes (LEDs) for data transmission.

LiFi is designed to use LED light bulbs similar to those currently inuse in many energy-conscious homes and offices.

However, LiFi bulbs are outfitted with a chip that modulates thelight imperceptibly for optical data transmission.

LiFi data is transmitted by the LED bulbs and received byphotoreceptors.

LED

Fluorescent Lamp

Transmitting Element

Transmitting elements

A high brightness white LED, Which act as a communication source.

Main Components of Communication System

Avalanche Photo Diode

Image Sensors

Receiving Element(Detector)

A silicon photodiode which shows good response to visible wavelength region serving as the receiving element.

Main Components of Communication System

Working of LI-FI The LEDs can be switched on and off very quickly which gives nice

opportunity for data transfer in the form of Binary code.

Switching ON an LED is logical ‘1’,switching off an LED is logical ‘0’.

Hence it is possible to encode the data into the LED’s by using a controller ,we just have to vary at which LED’s flicker depending on the data we want to encode to give different strings of 0’s and 1’s.

UK researchers say that using a micro-LED light bulb they have achieved a data transmission speed of 10Gbps using LI-FI.

Working of LI-FI

PA

PCB

The LIFI product consists of 4 primary sub-assemblies:

Bulb

RF power amplifier circuit (PA)

Printed circuit board (PCB)

Enclosure

LI-FI CONSTRUCTIONWorking of LI-FI

The PCB controls the electrical inputs and outputs of the lamp and houses the microcontroller used to manage different lamp functions. An RF (radio-frequency) signal is generated by the solid-state PA and is guided into an electric field about the bulb. The high concentration of energy in the electric field vaporizes the contents of the bulb to a plasma state at the bulb’s center; this controlled plasma generates an intense source of light. All of these subassemblies are contained in an aluminum enclosure

Working of LI-FI

FUNCTION OF THE BULB SUB-ASSEMBLY

At the heart of LIFI is the bulb sub-assemblywhere a sealed bulb is embedded in a dielectric material. more reliable than conventional light sources that insert degradable electrodes into the bulb.

The dielectric material serves two purposes; a waveguide for the RF energy transmitted by the PA an electric field concentrator that focuses energy in the bulb

The energy from the electric field rapidly heats the material in the bulb to a plasma state that emits light of high intensity and full spectrum

Working of LI-FI

Working of LI-FI

Working of LI-FIBlock Diagram

Advantageous Due To Parallel Data Transmission.

Working of LI-FI

Differences Between Technologies

Differences Between

Technologies

Li-1st, the first Li-Fi product

Applications

Applications

RF Spectrum Relief

Smart Lighting

Mobile Connectivity

Hazardous Environments

Hospital & Healthcare

Aviation

Underwater Communications

Vehicles & Transportation

RF Avoidance

Location Based Services (LBS)

Toys

Advantages

Higher speeds than Wi-Fi. 10000 times the frequency spectrum of radio.More secure because data cannot be intercepted without a clear

line of sight. Eliminates neighboring network interference. Unimpeded by radio interference. Does not create interference in sensitive electronics, making it

better for use in environments like hospitals and aircraft.

Disadvantages

Light can't pass through objects. A major challenge facing Li-Fi is how the receiving device will

transmit back to transmitter. High installation cost of the VLC systems Interferences from external light sources like sun, light, normal

bulbs, opaque materials .

Li-Fi Products

http://www.oledcomm.com/LIFISTORE/index.html

Chinese professor builds Li-Fi system with retail partsresearch costs at almost US$500,000

Strathclyde University develops LED Li-Fi internet connectionThe Engineering and Physical Sciences Research Council (EPSRC) is funding a consortium of UK universities, led by Strathclyde, to develop the technology

Li-Fi Usage

Conclusion

By using Li-Fi in all the lights in and around a building, thetechnology could enable greater area of coverage than asingle Wi-Fi router.

Drawbacks to the technology include the need for a clear line ofsight, difficulties with mobility and the requirement that lightsstay on for operation.

References

http://whatis.techtarget.com/definition/LiFi

http://www.dvice.com/archives/2012/08/lifi_ten_ways_i.php

http://electronicsforu.com/electronicsforu

http://purelifi.co.uk/what_is_li-fi/applicationsof_lifi/

http://en.wikipedia.org/wiki/Li-Fi