Li-Fi technology uses visible light communication and works by varying the intensity of light from LED bulbs to transmit data. One key advantage is that it can provide data rates faster than average broadband internet connections. The technology works by encoding data through strings of 1s and 0s by flickering high brightness LED lights on and off very rapidly. If developed further, it could allow every light bulb to function as a Wi-Fi hotspot to transmit wireless data, helping create a cleaner, greener, and safer future with improved connectivity.
Li-Fi is transmission of data through illumination by taking thefiber out of fiber optics by sending data through a LED lightbulb that varies in intensity faster than the human eye canfollow.
“At the heart of this technology is a newgeneration of high brightness light-emitting diodes”, saysHarald Haas from the University of Edinburgh, UK.”Verysimply, if the LED is on, you transmit a digital 1,
if it’s offyou transmit a 0,”Haas says, “They can be switched on and offvery quickly, which gives nice opportunities for transmitteddata.”
It is possible to encode data in the light by varying therate at which the LEDs flicker on and off to give differentstrings of 1s and 0s.The LED intensity is modulated so rapidlythat human eye cannot notice, so the output appears constant.
More sophisticated techniques could dramatically increaseVLC data rate. Terms at the University of Oxford and theUniversity of Edinburgh are focusing on parallel datatransmission using array of LEDs, where each LED transmits a different data stream. Other groups are using mixtures of red,green and blue LEDs to alter the light frequency encoding adifferent data channel.
Li-Fi, as it has been dubbed, has alreadyachieved blisteringly high speed in the lab. Researchers at theHeinrich Hertz Institute in Berlin, Germany have reached datarates of over 500 megabytes per second using a standardwhite-light LED.
Li-Fi is typically implemented using white LED light bulbs at the downlink transmitter. These devices are normally used for illumination only by applying a constant current. However, by fast and subtle variations of the current, the optical output can be made to vary at extremely high speeds. This very property of optical current is used in Li-Fi setup.The operational procedure is very simple-,data from the internet and local network is used to modulate the intensity of the LED light source if any undetectable to the human eye. The photo detector picks up signal, which is converted back into a data stream and sent to the client.
The client can communicate through its own LED output or over the existing network. An overhead lamp fitted with an LED with signal-processing technology streams data embedded in its beam at ultra-high speeds to the photo-detector. A receiver dongle then converts the tiny changes in amplitude into an electrical signal, which is then converted back into a data stream and transmitted to a computer or mobile device.
Li-Fi , or "light fidelity", refers to wireless communication systems using light from light-emitting diodes as a medium instead of traditional radio frequencies, as in technology using the trademark Wi-Fi. Li-Fi is expected to be ten times cheaper than Wi-Fi. Li-Fi has the advantage of being able to be used in electromagnetic sensitive areas such as in aircraft or nuclear power plants, without causing interference.
Unlike traditional Wi-Fi routers, which use radio signals, this LiFi system relies on light to send and receive data wirelessly. If you notice an Ethernet cable plugged into the laptops that’s just to get the data from the receiver into the computer. The problem with Wi-Fi is that it uses radio signals and the amount of radio spectrum is limited. LiFi, however, could be deployed in everyday LED bulbs and cover the entire interior of a home or office. The system on show ran at 150 Mbps, but with a more powerful LED light, it could reach 3.5Ghz.
Li-Fi is transmission of data through illumination by taking thefiber out of fiber optics by sending data through a LED lightbulb that varies in intensity faster than the human eye canfollow.
“At the heart of this technology is a newgeneration of high brightness light-emitting diodes”, saysHarald Haas from the University of Edinburgh, UK.”Verysimply, if the LED is on, you transmit a digital 1,
if it’s offyou transmit a 0,”Haas says, “They can be switched on and offvery quickly, which gives nice opportunities for transmitteddata.”
It is possible to encode data in the light by varying therate at which the LEDs flicker on and off to give differentstrings of 1s and 0s.The LED intensity is modulated so rapidlythat human eye cannot notice, so the output appears constant.
More sophisticated techniques could dramatically increaseVLC data rate. Terms at the University of Oxford and theUniversity of Edinburgh are focusing on parallel datatransmission using array of LEDs, where each LED transmits a different data stream. Other groups are using mixtures of red,green and blue LEDs to alter the light frequency encoding adifferent data channel.
Li-Fi, as it has been dubbed, has alreadyachieved blisteringly high speed in the lab. Researchers at theHeinrich Hertz Institute in Berlin, Germany have reached datarates of over 500 megabytes per second using a standardwhite-light LED.
Li-Fi is typically implemented using white LED light bulbs at the downlink transmitter. These devices are normally used for illumination only by applying a constant current. However, by fast and subtle variations of the current, the optical output can be made to vary at extremely high speeds. This very property of optical current is used in Li-Fi setup.The operational procedure is very simple-,data from the internet and local network is used to modulate the intensity of the LED light source if any undetectable to the human eye. The photo detector picks up signal, which is converted back into a data stream and sent to the client.
The client can communicate through its own LED output or over the existing network. An overhead lamp fitted with an LED with signal-processing technology streams data embedded in its beam at ultra-high speeds to the photo-detector. A receiver dongle then converts the tiny changes in amplitude into an electrical signal, which is then converted back into a data stream and transmitted to a computer or mobile device.
Li-Fi , or "light fidelity", refers to wireless communication systems using light from light-emitting diodes as a medium instead of traditional radio frequencies, as in technology using the trademark Wi-Fi. Li-Fi is expected to be ten times cheaper than Wi-Fi. Li-Fi has the advantage of being able to be used in electromagnetic sensitive areas such as in aircraft or nuclear power plants, without causing interference.
Unlike traditional Wi-Fi routers, which use radio signals, this LiFi system relies on light to send and receive data wirelessly. If you notice an Ethernet cable plugged into the laptops that’s just to get the data from the receiver into the computer. The problem with Wi-Fi is that it uses radio signals and the amount of radio spectrum is limited. LiFi, however, could be deployed in everyday LED bulbs and cover the entire interior of a home or office. The system on show ran at 150 Mbps, but with a more powerful LED light, it could reach 3.5Ghz.
LiFi is cellular wireless networking (re)using lights. Specifically, light emitting diodes (LEDs) are used in LiFi as visible light transmitters.
LiFi is a wireless optical networking technology that uses light-emitting diodes (LEDs) for data transmission. LiFi is designed to use LED light bulbs similar to those currently in use in many energy-conscious homes and offices.
Li-Fi uses common household LED (light emitting diodes) light bulbs to enable data transfer, boasting speeds of up to 224 gigabits per second.
LiFi is cellular wireless networking (re)using lights. Specifically, light emitting diodes (LEDs) are used in LiFi as visible light transmitters.
LiFi is a wireless optical networking technology that uses light-emitting diodes (LEDs) for data transmission. LiFi is designed to use LED light bulbs similar to those currently in use in many energy-conscious homes and offices.
Li-Fi uses common household LED (light emitting diodes) light bulbs to enable data transfer, boasting speeds of up to 224 gigabits per second.
LI-FI stands for “Light Fidelity”.
It is the transmission of data through illumination ,sending data through a Light Emitting Diode which varies in intensity faster than human eye can follow to deliver high speed data transmission.
Advantages of LI-FI
Higher Bandwidth (almost 10000 times more)
Availability
Efficiency
High Security
Easy to use
Fast data transfer
Harmless
Low cost
High capacity
Li-Fi can be thought of as a light-based Wi-Fi. That is, it uses light instead of radio waves to transmit information. And instead of Wi-Fi modems, Li-Fi would use transceiver-fitted LED lamps that can light a room as well as transmit and receive information. Since simple light bulbs are used, there can technically be any number of access points.
Li-Fi technology in Wireless Communicationdoddarangaiah
Li-Fi technology in woreless communication
The possibilities are numerous and can be explored further. If this technology can be put into practical use, every bulb can be used something like a Wi-Fi hotspot to transmit wireless data and will proceed toward the cleaner, greener, safer and brighter future.
The concept of Li-Fi is currently attracting a great deal of interest not least because it may offer a genuine and very efficient alternative to radio-based wireless. As a growing number of people and their many devices access wireless internet, the airwaves are becoming increasingly clogged, making it more and more difficult to get a reliable, high- speed signal.
This may solve issues such as the shortage of radio-frequency bandwidth and also allow internet where traditional radio based wireless is not allowed such as aircraft or hospitals. One of the shortcomings however is that it only work in direct line of sight.
2. Contents
Abstract
Introduction
Drawbacks Of Before Technologies
Different Between The Technologies
Working process
Applications
Advantages
Concussion
3. Abstract
One germen phycist. Harald Haas has come up
with a solution he calls “data through illumination” –
taking the fibber out of fibber optic by sending data
through an LED light bulb that varies in intensity faster
than the human eye can follow. It’s the same idea band
behind infrared remote controls but far more powerful.
Haas says his invention, which he calls D- LIGHT, can
produce data rates faster than 10 megabits per second,
which is speedier than your average broadband connection.
4. Introduction
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.
11. Working process
LIFI offers an integrated light source that is straightforward
to integrate into a projector. In this example LIFI consists
of 5 primary sub-assemblies:
Printed circuit board (PCB)
RF power amplifier (PA)
Bulb
Optics
Enclosure
15. Advantages
High Security
Easy To Use
Fast Data Transfer
Reliable
Harmless ness
Low Cost
16. Concussion
The possibilities are numerous and can be
explored further. If his technology can be put into
practical use, every bulb can be used something
like a Wi-Fi hotspot to transmit wireless data and
we will proceed toward the cleaner, greener, safer
and brighter future.