Presented By:- Krupa Shingala
Sep 21, 2014
Presented By:- Krupa Shingala
Introduction
History Of Network
Drawbacks Of Before Technologies
Why Only VLC?
What is VLC?
What is Li-fi?
Working process
Applications
Advantages & Disadvantages
Conclusion
Internet services are very highly demanding and essential accessories in current situation.
Presently we are utilizing the wired networks and mostly wireless networks like Wi-Fi in our houses, offices, shops, hotels, college campus and around 10-100 meter distances to connect our P.C., Laptops, Mobile Phones.
As present paper tells about the newly introduced Li-Fi technology network which is based the visible light communication that provide a fast data speed about greater than 10 Gbps.
In the olden days, People formed a network in order to transmit a piece of data from one place to another.
With the advances in technology a new networking was developed using wires as a medium ( wired networking ).
As time passed the technology increased and we launched satellites into space and thus were in a position to transmit enormous amount of data across various geographical location.
Wireless networking gained a wide recognition and become the most popular of all networks ( example ): Wi-Fi.
As technology keep on developing , the latest wireless network LI-FI is introduced to overcome disadvantages of radio frequency communication.
Radio spectrum 1.4 Million base stations, 5 billion Mobile stations 600tb data every per month
Radio Spectrum is congested but the demand for wireless data double each year. Everything, it seems want to use wireless data but the capacity is drying up.
Available within the range of Base stations
Limited availability
Unavailable in aircrafts
Less secure (passes through the walls)
Cost and Expensive
Less bandwidth compared to other spectrums
Harmful to humans health
Single data stream 10,000 or 20,000 bits per second Not usable for video streaming
CAN IT BE GAMMA RAYS ? NO
CAN IT BE X-RAYS ? NO X-RAYS HAVE SIMILAR HEALTH ISSUES
CAN IT BE UV RAYS? NO
CAN IT BE INFRARED WAVES ? NO
INFRARED, DUE TO EYE SAFETY REGULATION, CAN ONLY BE USED WITH LOW POWER.
HENCE WE ARE LEFT WITH ONLY THE VISIBLE - LIGHT SPECTRUM.
GAMMA RAYS ARE RADIOACTIVE AND DANGEROUS FOR HEALTH.
UV RAYS ARE HARMFUL FOR OUR SKIN AND CANNOT BE USED FOR LONG DURATION
Visible light communication ( VLC ) is a potential solution to the global wireless spectrum shortage.
Li-Fi technology is based on Visible Light communication.
VLC is a data communication medium, which uses visible light between 400 THz and 800THz as optical carrier for data transmission and illumination.
It uses fast pulses of light to transmit information wirelessly.
Li-Fi means “Light Fidelity”. At the heart of this technology is a new generation of
high brightness light-emitting diodes. It is possible to encode data in the light by varying the
rate at which the LEDs flicker on and off to give different strings of 1s and 0s.
LI-FI ( Light-Fidelity ) is transmission of data through illumination ,sending data through a LED light bulb that varies in intensity faster than human eye can follow.
German Physicist, Dr.Harald Haas a professor in university of Eddinburgh who began his research in the field in year 2004.
Harald Haas
Light power(LED) Multiple data streamHigh speed
The operation procedure is very simple, if the LED is on, you transmit a digital 1, if it's off you transmit a digital 0.
They can be switched on and off very quickly, which gives nice opportunities for transmitting data.
The main components of this communication systems are
A high brightness white LED, Which act as a communication source.
A silicon photodiode which shows good response to visible wavelength region serving as the receiving element.
Transmitting elementReceiving element
The functioning of new Li-Fi technology is just simple. You will have a light source at one end like a LED and a photo detector (Light Sensor) on the other end.
Used in airlines: Generally in airlines mobile phones can’t be used as they can effect the radars which are main way of communication.
Used in traffic lights which can communicate with cars to avoid accidents.
Street lamps(as free access points)
Larger bandwidth ( 10,000 times the radio bandwidth )
High speed data rate
High efficiency
Highly secure
Safe for health
More availability
Low cost solution
“ Presence of Light is Essential ’’
The possibilities are numerous and can be explored further. If this technology can be put into practical use, every bulb can be used as Li-Fi access point to transmit wireless data
and we will proceed toward the cleaner, greener, safer
&brighter future ! This may solve issues such as the shortage of radio
frequency bandwidth and also internet where radio based wireless isn’t allowed such as aircraft, Hospitals, etc…
Wikipedia
Lifeconsortium.org
Newtecarticles.com
Seminarprojects.com
Irjcjournals.org
extremetech.com