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Lifi Technology

Aug 19, 2014



A presention on LIFI technology..
Use MS Office 13 to view the original fonts and pics used within(as they are not supported in the previous versions..)

  • WIFI & its Problems 2
  • From using wireless internet in a coffee shop or stealing it from the guy next door to competing for bandwidth at a conference, the most probable cause of frustration is the decreasing speed due to more than one device being are tapped into the network. If we have a limited internet plan, say for example 5GB for 30days, then we have to make sure that that our network isnt being used by someone else( i.e. We have to password protect our network, thereby preventing unauthorized extra usage). The radio waves used for transmitting data in WIFI networks has detrimental impact on human health. 3
  • Introductio n to LIFI 4
  • Introduction to LIFI networks Data Through Illumination: A German physicist, Dr. Harald Haas, has come up with a solution to address the problems with WIFI networks, he calls Data Through Illuminationtaking the fiber out of fiber optics by sending data through an LED light bulb that varies in intensity faster than the human eye can follow. Light Fidelity: And this technology is calledLight Fidelity, popularly know as LIFI. 5G Visible Light Communication, Technology: LI-FI is 5G Visible Light Communication, Technology. The light from light emitting diodes (LEDs) is used as medium to deliver networked, mobile, high speed communication: The light is provided by light emitting diodes (LEDs) which acts as medium to deliver networked, mobile, high speed communication just as WI-FI or Optical fibre. With LIFI is possible to encode the data into the light by varying the rate at which the LEDs flicker ON and OFF which is too quickly to be noticed by the human eye. 5
  • Li-Fi is a Visible Light Communication (VLC), technology developed by a team of scientists including Dr. Gordon Povey, Prof. Harald Haas and Dr. Mostafa Afgani at the University of Edinburgh. Prof. Harald Haas 7
  • History 8
  • Professor Harald Haas, from the University of Edinburgh in the UK, is widely recognised as the original founder of Li-Fi. He coined the term Li-Fi and is Chair man of Mobile Communications at the University of Edinburgh and co-founder of pureLiFi. The general term visible light communication (VLC), includes any use of the visible light portion of the electromagnetic spectrum to transmit information. The D-Light project at Edinburgh's Institute for Digital Communications was funded from January 2010 to January 2012. Haas promoted this technology in his 2011 TED Global talk and helped start a company to market it. PureLiFi, formerly pureVLC, is an original equipment manufacturer (OEM) firm set up to commercialize Li-Fi products for integration with existing LED- lighting systems. 9
  • History (Contd) In October 2011, companies and industry groups formed the Li-Fi Consortium, to promote high-speed optical wireless systems and to overcome the limited amount of radio-based wireless spectrum available by exploiting a completely different part of the electromagnetic spectrum. VLC technology was exhibited in 2012 using Li-Fi. By August 2013, data rates of over 1.6 Gbit/s were demonstrated over a single color LED. In September 2013, a press release said that Li-Fi, or VLC systems in general, do not require line-of-sight conditions. In October 2013, it was reported Chinese manufacturers were working on Li-Fi development kits. Philips lighting company has developed a VLC system for shoppers at stores. They have to download an app on their smartphone and then their smartphone works with the LEDs in the store. The LEDs can pinpoint where they are at in the store and give them corresponding coupons and information based on where aisle they are on and what they are looking at. 10
  • Present Scenario VLC technology is ready right now; it's being installed in museums and businesses across France, and is being embraced by EDF, one of the nation's largest utilities. The First VLC smartphone prototype was presented at the Consumer Electronics Show in Las Vegas from January 710 in 2014. The phone uses SunPartner's Wysips CONNECT. A clear thin layer of crystal glass can be added to small screens like watches and smartphones that make them solar powered. Smartphones could gain 15% more battery life during a typical day. This first smartphones using this technology should arrive in 2015. This screen can also work to receive VLC signals and so can the smartphone camera. The cost of these screens per smartphone is between $2 and $3, much cheaper than most new technology. 11
  • Why LIFI? 12
  • Present Scenario More than 338 MillionMore than 1.8 Million 13
  • Issues Regarding Radio Spectrum Capacity Efficiency Security Availability 14
  • Different Electromagnetic Spectrums and their potentiality Radio Waves Infrared Visible Ultraviolet X Rays Gamma Rays In sufficient spectrum for increasing data Low power application Which is not used so far. Dangerous for human body Used for hospitals and security checking It is not used generally 15
  • How LIFI works? 16
  • White LED light bulbs: Li-Fi is typically implemented using white LED light bulbs at the downlink transmitter which normally used for illumination only by applying a constant current. Optical output is varied at extremely high speed: The LEDs can be switched on and off very quickly which gives nice opportunity for data transfer in the form of Binary code. Hence, 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. Operational Procedure: The operational procedure is very simple-, if the LED is on, you transmit a digital 1, if its off you transmit a 0. Hence it is possible to encode the data into the LEDs by using a controller ,we just have to vary at which LEDs flicker depending on the data we want to encode to give different strings of 0s and 1s. UK researches say that using a micro-LED light bulb they have achieved a data transmission speed of 10Gbps using LI-FI. 17
  • Non technical Perspective 10,000 times as broad a spectrum as the radio frequencies which Wi-Fi uses: Visible light has 10,000 times as broad a spectrum as the radio frequencies which Wi-Fi uses, allowing for much more bandwidth, once tapped. Light bulbs are made to flicker at extremely high speed that human eye cant detect: This is accomplished by the flickering of LED light bulbs to create binary code (on = 1, off = 0), and is done at higher rates than the human eye can detect. Shed a couple of extra bucks on the lighting solution and get an incredibly fast internet connection: Which basically means The more LEDs in your lamp, the more data it can process, and by shedding a couple of extra bucks on the lighting solutions of your housing or office youre getting an incredibly fast and secure internet connection. 18
  • Properties of LIFI Light-based Wi-Fi: LIFI 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. Unutilized electromagnetic spectrum is used: This technology uses a part of the electromagnetic spectrum that is still not greatly utilized. The Visible Spectrum. No major ill effect: Light is in fact very much part of our lives for millions and millions of years and does not have any major ill effect. 19
  • Components of a LIFI Communication System 20
  • Source A high brightness white LED, acts as a communication source Its guided by the PCB and powered by PA and is enclosed in an aluminum enclosure Bulb: The high concentration of energy in the electric field vaporizes the contents of the bulb to a plasma state at the bulbs center; this controlled plasma generates an intense source of light. RF power amplifier circuit (PA): An RF (radio-frequency) signal is generated by the solid-state PA(Power Amplifier) and is guided into an electric field about the bulb. Printed circuit board (PCB): The PCB controls the electrical inputs and outputs of the lamp and houses the microcontroller used to manage different lamp functions. Enclosure: All of these subassemblies are contained in an aluminum enclosure 21
  • Receiver A silicon photodiode, which shows good response to visible wavelength regi