Lifi technology documentation
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1. The document discusses a new technology called Li-Fi that transmits data through LED light bulbs by varying the intensity of light faster than the human eye can detect. This allows for wireless internet access through light. 2. One inventor, Dr. Harald Haas, developed this technology called "Data Through Illumination" which he claims can transmit data faster than average broadband speeds. He envisions wireless internet access for devices through light in a room. 3. The technology works by varying the intensity of LED lights to transmit binary code for "0" and "1" much like how infrared remote controls work but at higher speeds and amounts of data. This could provide wireless internet access through normal light in homes
Lifi technology documentation
- 1. ABSTRACT Whether you’re using wireless internet in a coffee shop, stealing it from the guy next door, or competing for bandwidth at a conference, you’ve probably gotten frustrated at the slow speeds you face when more than one device is tapped into the network. As more and more people and their many devices access wireless internet, clogged airwaves are going to make it. One German physicist ,DR. Harald Haas, has come up with a solution he calls ―Data Through Illumination‖—taking 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. It’s the same idea 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. He envisions a future where data for laptops, Smartphone’s, and tablets is transmitted through the light in a room. And security would be a snap—if you can’t see the light, you can’t access the data. LIFI TECHNOLOGY Page 1
- 2. 1. INTRODUCTION: Li-fi basically known as ―LIGHT FEDILITY‖ is an outcome of twenty first century. The basic ideology behind this technology is that the data can be transmitt ed through LED li ght whose int ensit y varies even faster than the human eye. As the transmission of the data takes place through the light emitting diodes (LED’s) the amount is comparatively small .In modern times, it is called as the optimized version of WI-FI .The advantageous thing is the wireless communication which decreases the cost enormously. HARALD HASS, who is considered to be the father of Li-fi from university of Edinburgh, UK says that the heart of this technology lies in the intensity and the potential of the light emitting diodes. The major reason which lead the modern man through this invention is that the confinement of Wi-Fi to comparatively small distance. As there are more and more devices coming up day-by-day the signals are being clogged up due to heavy traffic, there arised a need for an error free transmission technology. And the solution to this problem was the Li-fi technology.. It has been designed in such a way that it overcomes the disadvantages that occurs during the usage of wi-fi. In general terms, Li- fi works even under water thereby causing a great benefit to the military operations. LIFI TECHNOLOGY Page 2
- 3. The phycists envisions that this technology would make a great difference between the assumption and the proof in this case .The demonstration took place using two Casio smart phones. The data was made to exchange between the phones using light. Even though the distance was nominal, it is sure that there would be a rapid increase in the distance of transmission.AS there is a limited amount of Radio based wireless spectrum available, a number of companies formed a consortium called Li-fi consortium in order to promote high speed optical wireless systems .The members of this consortium believes that a speed of 10 Gbps can be achieved in no time. If this would be possible then a high clarity image would take about 30 seconds to download!! LIFI TECHNOLOGY Page 3
- 4. 2. HISTORY: Haraald Haas continues to hit the world that there is a possibility for communication through light.LI-FI technology has the possibility to change how we access the internet, stream videos, receive emails and much more. The technology truly began during the 1990's in countries like Germany, Korea, and Japan where they discovered LED's could be Haraald Haas continues to hit the world that there is a possibility for communication through light.LI-FI technology has the possibility to change how we access the internet, stream videos, receive emails and much more. The technology truly began during the 1990's in countries like Germany, Korea, and Japan where they discovered LED's could be retrofitted to send information. This type of light would come in familiar forms such as infrared, ultraviolet and visible light. Research into VLC has been conducted in earnest since have shown that LEDs can be electronically adapted to transmit data wirelessly as well as to provide light. VLC is faster, safer and cheaper than other forms of wireless internet, advocates say -- and so could eliminate the need for costly mobile-phone radio masts. Fig 1. Haralad Hass LIFI TECHNOLOGY Page 4
- 5. Haas has a small lab stuffed with equipment, including the now-famous table lamp and its box of electronics. It was here in 2007 that his research assistant, Mostafa Afgani, first sent data using light signals. Haas's invention centres on how these signals are modulated: the information, embedded within visible light emitted from the LEDs, is trans- mitted by means of many subtle changes made to the intensity of the light at the ultra-high rate of 100 million cycles per second (100MHz). The photodetector in Haas's box monitors these tiny variations and converts them back into a digital signal, from which the transmitted information is extracted. In October 2011 a number of companies and industries formed the Li-Fi Consortium, to promote high-speed optical wireless system sand to enhance the limited bandwidth provided by radio-based wireless spectrum available. The consortium believes it is possible to achieve more than 10Gbpsspeed using this optical wireless technology also known as Li-Fi. The communication is done by deploying transmit- ter and receiver in direct line of sight manner. It gets affected if line of sight is not used, the speed of data transmission will reduce or data transmission will stop. It is also more secure than other wireless net- works as only photo receptors are used, which can receive data within transmitted cone of light signals. LIFI TECHNOLOGY Page 5
- 6. 3 .WORKING OF LI-FI In order to know the working of Li-fi we need to know the necessity for Li-fi .With the vast development in living the use of gadgets and invention of new gadgets is increasing which lead to the technological developments. FIG: 2 Construction of lifi technology There are many situations in which people get frustrated with the dull performance signals of Wi-Fi at a place with many network connections in seminars conferences etc. Li fi fulfills these needs .this fantabulous idea first striked the mind of Harald Haas from University of Edinburgh, UK, in his TED Global talk on VLC.His idea was very simple that if the LED is ―on‖ then the digital 1 can be transmitted and if the led is ―off‖ then the digital 0 can be transmitted. Led’s can be switched on and off very quick. For transmitting data this way all that we require is LED’s and controller that code data into Led’s. Parallel data transmission can be done by using array of LED’s or by using red, green, blue LED’s to alter light frequency with the frequency of different data channel. Advancements and enhancements in this field generate a speed of 10 gbps! But amazingly fast data rates and lowering band widths are not the only reasons that enhance this technology. Lifi usually is based on light and so it can be probably implemented in articrafts and hospitals that are prone to inference from radio waves. Unlike Wi-Fi Li-Fi LIFI TECHNOLOGY can work even under- water which makes it more Page 6
- 7. advantageous for military operations. Radio waves are replaced by light waves in data transmission called Li- Fi. Light emitting diodes can be switched on and off very much faster than the human eye allowing the light source to appear continuously. The data transmission is done through binary codes which involve switching on LED can be done by logic 1 and switch off using logic 0.The encoding of information in light can therefore be identified by varying the rate at which the LED’s flicker on and off to give strings of 0’s and 1’s.visible light communication is this method of using rapid pulses of light to transmit information wirelessly. 3.1 Visible Light Communication: VLC is a data communication Medium, which uses visible light between 400 THz (780 nm) and 800 THz (375 nm) as optical carrier for data transmission and illumination. Fast pulses are used for wireless transmission. Communication system components are: 1. A high brightness white LED which acts as a communication source 2. Silicon photo diode which shows good response to visible wavelength region. LED illumination can be used as a communication source by modulating the LED light with the data signal. The LED light appears constant to the human eye due to the fast flickering rate. The high data rate can be achieved by using high speed LED’s and appropriate multiplexing tech- niques. Each LED transmits at a different data rate which can be in- creased by parallel data transmission using LED arrays. Many different reasons exist for the usage of LED light in spite of fluorescent lamp, incandescent bulb etc which are available. LIFI TECHNOLOGY Page 7
- 8. Fig 3: Transfer of data in the form of 0’s and 1’s 3.2 Present Scenario: We have 1.4 million cellular mast radio waves base stations deployed We also have over 5 billions of mobile phones Mobile phone transmits more than 600 Tb of data Wireless communication has become a utility like electricity & water We use it in our everyday life, in our private life, business life Currently WiFi uses Radio Waves for communication It is important to look into this technology which has become fundamental to our life Four Issues with radio waves 1. Capacity : We transmit wireless data through radio waves Radio waves are limited Radio waves are scar and expensive We only have a certain range of it With the advent of the generation technology as of like of 2.5G,3G,4G and so on we are running out of spectrum. LIFI TECHNOLOGY Page 8
- 9. 2. Efficiency : There are 1.4 million cellular radio base stations They consume massive amount of energy Most of this energy is not use for transmission but for cooling down the base stations Efficiency of such a base station is only 5% and that raise a very big problem 3. Availability : Availability of radio waves or rf singnals causes another concern We have to switch off our mobiles In aero planes It is not advisable to use mobiles at places like petrochemical plants and petrol pumps 4. Security : Radio waves penetrates through walls They can be intercepted If someone has a knowledge and bad intentions than he may misuse it Alternative to radio waves in Electromagnetic spectrum So there are four major concerns i.e., capacity, efficiency, availability and security related with radio waves But on the other hand we have 40 billions of light box already installed and light is part of electromagnetic spectrum So let’s look up at this in context of EM spectrum Radio waves Infra red Visible Ultra violet X rays Gamma rays Electromagnetic spectrum Gamma rays are simply very dangerous and thus can’t be used for our purpose of communication X-rays are good in hospital and can’t be used either Ultra –violet rays are sometimes good for our skin but for long duration it is dangerous LIFI TECHNOLOGY Page 9
- 10. Infra red rays are bad for our eyes and are therefore use at low power levels We have already seen shortcoming of radio waves So we are left with only visible light spectrum. Light for WiFi communication Light has been around for millions of years. It has created us, has created life and has created all stuffs of life. FLICKERING lights are annoying but they may have an upside. Visible light communication(VLC) uses rapid pulses of light to transmit information wirelessly, now it may be ready to compete with conventional WIFI. So it is inherently safe use and would be great if we can use it for our wireless communication. What we have to do? We have to replace inefficient fluorescents lights with this new dignitaries of LED lights. It is a semi conductive e-device. The LED bulb will hold a micro chip that will do the job of processing the data. Light intensity can be modulated at very high spends to send data tiny changes in amplitude. LIFI TECHNOLOGY Page 10
- 11. How we do this? Remote control has as IR-led It creates a single data stream. High speed data rates of 10000 b/s to 20000b/s Replace remote control with light box With this technology we transmits 1000’s of data stream in parallel at high speeds. We termed this technology as special Modulation. 3.3 comparisons between LIFI AND WIFI: LIFI is a term of one used to describe visible, light communication technology applied to high speed wireless communication. It acquired this name due to the similarity to wifi,only light instead of radio. WI-FI is great for general wireless coverage within buildings, and li-fi is ideal for high density wireless data coverage in confined areas and for relieving interference issues, so the two technologies can be considered complimentary. Technology Wireless(current) Wi-Fi- IEEE 802.11n Bluetooth IrDA Wireless(future) wiGig Giga-IR Li-Fi Speed Data density 150 Mbps 3 Mbps 4 Mbps * * *** 2 Gbps 1 Gbps >1 Gbps ** *** **** Comparision table of wifi & lifi technology The table also contains the current wireless technologies that can be used transferring data between devices today,i.e Wi-Fi, Bluetooth and IrDA. Only WI-FI currently offers very data rates. The IEEE 802.11n in most implementations provides up to 150Mbps LIFI TECHNOLOGY Page 11
- 12. although in practice you receive considerably less than this. Note that one out of three of these are an optional techonology 3.4 Replacement for others technologies This technology doesn’t deal with radio waves, so it can easily be used in the places where Bluetooth, infrared, WIFI and Internet are banned. In this way, it will be most helpful transferring medium for us.It includes other benefits like: *A very wide spectrum over visible wave length range. * Extremely high colour fidelity. *Instant start time. *Easy terminal Management. *Dynamic dark i.e. brightness Modulation of lamp output to enhance video contrast. *Trouble-free integration into existing light engine platform. Li-Fi is the upcoming and on growing technology acting as competent for various other developing and already invented technologies. Since light is d major source for transmission in this technology it is very ad- vantageous and implementable in various fields that can’t be done with the Wi-Fi and other technologies. Hence the future applications of the Li-Fi can be predicted and extended to different platforms like education LIFI TECHNOLOGY Page 12
- 13. 4. APPLICATIONS: There is a wide necessity for data transfer and by the end of the day every field involves the use of technologies. One such technology is Li-Fi which can have its applications extended in areas where the Wi-Fi tech- nology lack its presence like medical technology, powerplants and various other areas where Li-Fi proved it excellence of the undersea awesomeness. At present its applications ate beyond imagination but still if to think about few then they are : Can be used in the places where it is difficult to lay the optical fiber like hospitals. In operation theatre LiFi can be used for modern medical instruments. In traffic signals LiFi can be used which will communicate with the LED lights of the cats and accident numbers can be decreased. Thousand and millions of street lamps can be transferred to LiFi lamps to transfer data. In aircraft LiFi can be used for data transmission. It can be used in petroleum or chemical plants where other transmission or frequencies could be hazardous. 4.1 Future applications: 4.1.1 Education systems: As with the advancement of science the latest technology is the LIFI which is the fastest speed internet access service. so this will leads to the replacement of WIFI at institutions and at companies so that all the peo- ple can make use of LIFI with same speed intended in a particular area. LIFI TECHNOLOGY Page 13
- 14. 4.1.2 Extends our life span: As operation theatres do not allow WIFI due to radiation concerns. Usage of WIFI at hospitals interferes with the mobile and pc which blocks the signals for monitoring equipments. Therefore the replacement for this WIFI is Li-Fi as Hass has mentioned in his TED TALK that LIFI has 10,000 times the spectrum of WIFI. Because the lights are not only allowed in operation theatres but also the most dazzling fixtures in the room. 4.1.3 Reduction in accident numbers: At traffic signals, we can use LIFI in order to communicate with LED lights of the cars by the number of accidents can be reduced. Data can be easily transferred by making use of LIFI lamps with the street lamps. 4.1.4 Replacement for others technologies: This technology doesn’t deal with radio waves, so it can easily be used in the places where Bluetooth, infrared, WIFI and Internet are banned. In this way, it will be most helpful transferring medium for us. It includes other benefits like: A very wide spectrum over visible wave length range. Extremely high colour fidelity. Instant start time. Easy terminal Management. Dynamic dark i.e. brightness Modulation of lamp output to enhance video contrast. Trouble-free integration into existing light engine platform Li-Fi is the upcoming and on growing technology acting as competent for various other developing and already invented technologies. Since light is d major source for transmission in this technology it is very advantageous and implementable in various fields that can’t be done with the Wi-Fi and other technologies. Hence the future applications of the Li-Fi can be predicted and extended to different platforms like education. LIFI TECHNOLOGY Page 14
- 15. 5 .CONCLUSION: Li-Fi is the upcoming and on growing technology acting as competent for various other developing and already invented technologies. Since light is d major source for transmission in this technology it is very advantageous and implementable in various fields that can’t be done with the Wi-Fi and other technologies. Hence the future applications of the Li-Fi can be predicted and extended to different plat- forms like education fields, medical field, industrial areas and many other fields. 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 we will proceed towards the cleaner, Greener, Safer and Brighter future. LIFI TECHNOLOGY Page 15
- 16. 6.REFERENCES: 1. http://en.wikipedia.org/wiki/Li-Fi 2. http://www.scribd.com/doc/88377913/Synopsis-on-Lifi-The-latesttechnology-in-wireless-communication. 3. http://www.scribd.com/doc/88340668/Seminar-Report-on-LiFi LIFI TECHNOLOGY Page 16