Li-Fi (Light Fidelity)-The future technology In Wireless communication

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 have 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 fibber out of fiber 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 DLIGHT, 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, smart phones, and tablets is transmitted through the light in a room. And security would be snap –if you can't see the light, you can't access the data.

International Journal of Engineering Research and Technology (IJERT), 2013

https://www.ijert.org/li-filight-fidelity-technology https://www.ijert.org/research/li-filight-fidelity-technology-IJERTV2IS110544.pdf This latest Technology LI-FI describes transmission of "data through illumination" taking the fibre out of fibre 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. Harald 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, smart phones, and tablets is transmitted through the light in a room. And security would be snap-if you can't see the light, you can't access the data.

IJRCAR, 2015

Motivated by the looming radio frequency (RF) spectrum crisis, this paper aims at demonstrating that optical wireless communication (OWC) has now reached a state where it can demonstrate that it is a viable and matured solution to this fundamental problem.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 have 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 germen phycist.Harald Haas has come up with a solution he calls ―data through illumination‖ –taking the fibber out of fiber optic by sending data through an LED light bulb that varies in intensity faster than the human eye can follow.Optical attocells are the next step in the progression towards ever smaller cells, a progression which is known to be the most significant contributor to the improvements in network spectral efficiencies in RF wireless networks.Haas says his invention, which he calls DLIGHT, can produce data rates faster than 10 megabits per second, which is speedier than your average broadband connection.

— At the time of using wireless internet at any place whether it is own or stealing from others, one has probably gotten frustrated because of the slow speed of internet when more devices are connected to a single router. Due to increasing of internet users exponentially, Radio Spectrum is congested but the demand for wireless data double each year. Dr. Harald Haas has come up with a solution for those he calls " Data through illumination ". LI-FI is a new epoch of high intensity light source of solid state design which bring clean lighting solutions to general and specialty lighting. LI-FI is now part of the VLC as is implemented using white LED light bulbs. Data transmission takes place from this LED bulb by varying the current at extremely high speeds which undetectable by the human eye.

International Journal of Science Technology & Engineering

Nowadays many people are taking interest as to accomplish their tasks through wired or wireless networks. As numbers of users get increased in wireless network the speed reduces proportionally. Though Wi-Fi gives us speed up to 150 Mbps as per IEEE 802.11n. it is still insufficient to accommodate desired no of users. To remedy this limitation, we are introducing the concept of Li-Fi. As per German physic Harald Haas “data through illumination” –taking the fiber out of fiber optic by sending data through an LED light bulb that varies in intensity faster than the human eyes can follow. It’s the same idea band behind the infrared remote controls but far more powerful. Haas says his invention, which he calls D-LIGHT, can produce data rates faster than 10 Mbps, which is speedier than average broadband connection. Twentieth century is an era of internet. Most of the communications happen over the internet. Wi-Fi is the currently most advanced technology that is being widely used for connecting to the internet. The speed and the number of users that can connect at a time are limited in Wi-Fi. Our project is about visible light communication. This communication happens using light as a medium. As light is going to act as a medium the speed will be tremendous for data transmissions. Not only speed but also the security in a closed environment will increase with the use of Li-Fi. Our project aims at exploring the use of Li-Fi also known as optical wireless communication.

Current era many people are using internet to accomplish their task through wired or wireless network. As no of users get increased in wireless speed decreases proportionally. Though Wi-Fi gives us speed up to 150mbps as per IEEE 802.11n, it is still insufficient to accommodate no of users. To remedy this limitation of Wireless Fdilityi, we are introducing concept of Li-Fi. As per germen phycist Harald Haas data through illumination taking the fibber out of fiber 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. Light-Fidelity is a label for wireless-communication systems using light as a carrier instead of traditional radio Frequencies [1], as in Wi-Fi. Li-Fi has the advantage of being able to be used in sensitive areas such as in Aircraft and other transportation without causing interference. However, the light waves used cannot penetrate walls. It is typically implemented using white LED bulbs at the Downlink transmitter. This type of 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 property of optical current is used in Li-Fi setup. The operational procedure is very simple-, if the LED bulb is on, you transmit a digital 1, if it's off you transmit a 0. The LEDs can be switched on and off very quickly, which gives nice opportunities for transmitting data. Hence all that is required is some LEDs and a controller that code data into those LEDs. All one has to do is to vary the rate at which the LED's flicker [2] depending upon the data we want to encode. Further enhancements can be made in this method, like using an array of LEDs for parallel data transmission, or using mixtures of red, green and blue LEDs to alter the light's frequency with each frequency encoding a different data Channel. Such advancements promise a theoretical speed of 10 Gbps-meaning one can download a full high-definition film in just 30 seconds.

Li-Fi stands for Light-Fidelity. Li-Fi technology, proposed by the German physicist-Harald Haas, provides transmission of data through illumination by sending data through an LED light bulb that varies in intensity faster than the human eye can follow. This paper focuses on developing a Li-Fi based system and analyzes its performance with respect to existing technology. Wi-Fi is great for general wireless coverage within buildings, whereas Li-Fi is ideal for high density wireless data coverage in confined area and for relieving radio interference issues. Li-Fi provides better bandwidth, efficiency, availability and security than Wi-Fi and has already achieved blisteringly high speed in the lab. By leveraging the low-cost nature of LEDs and lighting units there are many opportunities to exploit this medium, from public internet access through street lamps to auto-piloted cars that communicate through their headlights. Haas envisions a future where data for laptops, smart phones, and tablets will be transmitted through the light in a room.

International Journal of Computer Applications, 2016

A person gets frustrated when he faces slow speed as many devices are connected to the same network. As the number of people accessing wireless internet increases, it's going to result in clogged airwaves. Li-Fi is transmission of data through illumination by taking the fiber out of fiber optics by sending data through a LED light bulb that varies in intensity faster than the human eye can follow. As Li-Fi is considered to be the optical version of Wi-Fi, some label it as fast and cheap wireless communication system. When LED is on digital 1 is transmitted and when it is off 0 is transmitted. Data can be encoded in the light by varying the flickering rate to generate strings of 1s and 0s. The output appears to be constant to the human eye as the LED intensity is modulated rapidly. This method of using rapid pulses of light to transmit information wirelessly is technically referred to as Visible Light Communication (VLC). Advancements promise a speed of 10 Gbps. Li-Fi can work even underwater. 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 a cleaner, greener, safer and brighter future. As the growing number of device accessing wireless internet are coming into use airwaves are becoming increasingly clogged making it more and more difficult to get a reliable, high speed signal.

— In the present time, Wi-Fi is the most drifting area. As web customers are increasing consistently, there is an enormous load on radio range that leads to congestion. To show signs of improvement in data transfer, capacity and speed, another innovation Li-Fi has progressed. Li-Fi stands for Light Fidelity. It is a bidirectional and remote method for communication utilizing light. It utilizes the unused visible range and decreases the load on radio frequency range. Li-Fi can just be used instead of Wi-Fi with light used as the medium as opposed to radio waves. Here, information is transmitted utilizing light whose frequency differs quicker than human eye to catch. Rather than utilizing modems, Li-Fi utilizes LED bulbs with handset. Information transmission in Li-Fi is around 100 times speedier than Wi-Fi. Here, in this paper we discuss the requirement for Li-Fi. Li-Fi is a type of optical remote innovation that utilizes light as the medium to transmit information in the visible range (Visible Light Communication {VLC}). The Li-Fi with which one can browse new sites in a matter of seconds and which makes it profoundly secure is discussed.