Presented by: Sirajuddin Qureshi2k13-MSIT-32
Subject Teacher:- Respected Sir Dr. Mansoor Hyder A Presentation on Light-Fidelity: A Reconnaissance of Future Technology
Haas, Harald (July 2011). "Wireless data from every light bulb. At TEDGlobal, Harald Haas demonstrates,Research Paper of Dhakane Vikas Nivrutti, Ravi Ramchandra Asst. Professor Solapur University, College of Engineering, India Light-Fidelity: A Reconnaissance of Future Technology
Li-fi basically known as light fidelity .
Use of the visible light portion of the electromagnetic spectrum to transmit information.This technology uses a part of the electromagnetic spectrum that is still not greatly utilized- The Visible Spectrum.
LED light bulbs are turned into high speed wireless communication devices, a bit like a Wi-Fi, hence the name Li-Fi
Why only VLC can replace radio communication..
The general term visible light communication (VLC), includes any use of the visible light portion of the electromagnetic spectrum to transmit information. The term Li-Fi was coined by Harald Haas from the University of Edinburgh in the UK. 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.Prof. Harald HaasUniversity of Edinburgh.
The LEDs can be switched on and off very quickly which gives nice opportunities for transmitting data.
The working procedure is very simple, if the light is on then transmit a digital 1, if its off transmit a 0.
On one end all the data on the internet will be streamed to a lamp driver when the LED is switched on the microchip converts the digital data in form of light. The light sensitive device photo detector receives the signal and converts it back into original data.
This method of using rapid pulses of light to transmit information wirelessly is technically referred as Visible Light Communication.
DataModulationPhoto DictatorDemodulationDataLight Source
Transmitting ElementsLEDImage SensorsAvalanche Photo DiodeReceiving ElementFluorescent Lamp
Li-Fi can be thought of as a light-based Wi-Fi. That is, it uses light instead of radio waves to transmit information.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.
Li-Fi can used in sensitive areas such as aircraft from data transmission without causing interference.
Thousands and millions of streets lamps can be transferred to Li-Fi lamps to transfer data.
It can used in Petroleum and Chemical Plants where others Transmission or Frequencies could be Dangerous.
It can be used underwater where Wi-Fi totally failed .
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 speedEnergy EfficiencyHigh speed data transferIts main advantage is its bandwidth, It is 10,000 times than the radio wavesCost Benefits
Presence of Light is essential
There will be interference from sunlight
You need special LEDs.
A Major Challenge facing Li-Fi is how the receiver devices will transmit back to Transmitter.
In figure a internet connection is connected to the lamp driver . A switch connected with lamp driver and LED lamp also connected this lamp driver through fiber optics cable. Now a receiving device named photo detector is using for receive signal and processing , this device is connected with PC or Laptops LAN port. *