Li-Fi, VISIBLE LIGHT COMMUNICATION

Contents

Introduction to Li-Fi

Li-Fi Construction / Working

Features of Li-Fi Technology

Advantages of Li-Fi Technology

Applications of Li-Fi Technology

Li-Fi Vs Wi-Fi

Drawbacks & Ongoing Research

Introduction to Li-Fi / Visible Light Communication

What is Li-Fi / VLC ?

Use of the visible light portion of the electromagnetic spectrum to transmit information.

LED light bulbs are turned into high speed wireless communication devices, a bit like a Wi-Fi, hence the name Li-Fi

Introduction to Li-Fi / Visible Light Communication

Professor Harald Haas, an expert in optical wireless communications

The D-Light project  

Haas promoted this technology in his 2011 TED Global talk

Pure Li-fi, formerly pure VLC, is an original equipment manufacturer (OEM) firm set up to commercialize Li-Fi products

Vs

Li-Fi Vs Wi-Fi

PRESENT SCENARIO:

We have 1.4 million cellular radio waves base stations

deployed.

We also have over 5 billion of mobile phones.

Wireless communication has become a utility like electricity

& water.

Currently Wi-Fi uses Radio waves for communication.

Four Issues with Radio Waves:

Capacity

Efficiency

Availability

Security

Li-Fi Vs Wi-Fi

Li-Fi, or light fidelity, refers to 5G visible light communication system

optical orthogonal frequency-division multiplexing (O-OFDM)

The LIFI product consists of 4 primary sub-assemblies

• Bulb

• RF power amplifier circuit (PA)

• Printed circuit board (PCB)

• Enclosure

Li-Fi Construction / Working

Li-Fi Construction / Working

The heart of LIFI is dielectric material.

The dielectric material serves two purposes

1)As a wave guide for the RF energy transmitted by the PA

2) As an electric field concentrator that focuses energy in the bulb.

Li-Fi Construction / Working

If the LED is on, you transmit a digital 1, if it’s off you transmit a 0.

Convert Light to Data

We have to just vary the rate at which the LED’s flicker

Red, Green and Blue LEDs for different data channel.

Such advancements promise a theoretical speed of 10 GBps –i.e. you can download a full high-definition film in just 30 seconds.

Li-Fi Construction / Working

Li-Fi Construction / Working

Li-Fi Construction / Working

Li-Fi Construction / Working

1. Distance

2. Cost

3. Traffic Updates

4. Game Consoles

5. Television Interaction

Five Reasons to Promote Li-Fi Technologies

Features of Li-Fi Technologies

It is two way communications that uses medium of light.

It is a safe technology to transfer confidential matters. 

Fluorescent light transmits a meaningful amount of data by

frequently flickering

The preferred light sources are fluorescent lights and LEDs.

Photo diodes are used as receivers which can turn light into

electrical signals

Every source of lights can be used as transmitter in VLC

Advantages of Li-Fi Technologies

Long service life (10-15 years while usual bulbs last 1-2

years)

Energy Saving (8W LED bulb=60W ordinary Bulb)

Light emitting Diodes are a source of light (release large

amount of energy in the form of light)

Can be switched on/off at very high speed

Energy Efficiency

High speed data transfer

It’s main advantage is it’s bandwidth, It is 10,000 times

than the radio waves

Cost Benefits

Applications of Li-Fi Technologies

Applications of Li-Fi Technologies

Applications of Li-Fi Technologies

Applications of Li-Fi Technologies

Applications of Li-Fi Technologies

Applications of Li-Fi Technologies

What will be the effect of interferences from external light

sources like sun light & normal bulbs?

What about the limited bandwidth of the existing copper

cables used for electrical connections?

Where do the connections uplink, how serious are the

modifications needed to the power grid?

How will other devices react if you inject a high frequency

into mains?

Initial setup cost.

Presence of light is essential.

There should be line of sight.

Drawbacks and ongoing Research of Li-Fi Technologies

Li-Fi Concept Animated By K.SASHI KUMAR

Li-Fi Gadgets

Conclusion

Any Queries….?