87th BLOG POST -->>
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| How Li Fi Works |
Here we are meeting first time in 2015. Last year was
only for travelling to different places of Rajasthan, Haryana and Delhi. One of
the best moment was of Surya Foundation Trip with 70 friends belong to all over
India means of different state. In Surya foundation, many compilations were organized
which were very helpful. During that camp I get a chance to give speech on a
topic. And also participated in many events in a week. Rest about the participated
related task I will talk in next blog post. I promise I’ll post in coming days
so ready of that post.
Today I want to post a technical post. Perhaps it will
be first time I’m going to post technical information. Today technology changed
per day. Every day I try to learn something special from technologies. But we
get knowledge’s about these technical topics then we not get such platform
where we present our technical skill. But I was in this case; I get 7 days to
represent some knowledge of information technology in a school and after that
one day in seminar. Where I choose a technical topic for seminar was Li-FI
Technology. I am sure most of you reader don’t know about this
technology. When in seminar hall I say Li-FI Technology, for a moment in
seminar hall sanata cha gya….!! What you say… ye kya hota hai … etc etc. Even I
think here also such questions were come in your mind. Below I’m giving some
information related to this technology.
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 increasingly difficult to latch onto a reliable signal. But radio waves are just one part of the spectrum that can carry our data. What if we could use other waves to surf the internet? For all this we’ve a solution 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.
Li-Fi is now part of the Visible Light Communications (VLC) PAN IEEE 802.15.7 standard. Li-Fi is typically implemented using white LED light bulbs. These devices are normally used for illumination by applying a constant current through the LED. However, by fast and subtle variations of the current, the optical output can be made to vary at extremely high speeds. Unseen by the human eye, this variation is used to carry high-speed data. In simple terms, 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 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-, if the LED 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 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.
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| Working Technology of Li Fi |
Light is inherently safe and can be used in places
where radio frequency communication is often deemed problematic, such as in
aircraft cabins or hospitals. So visible light communication not only has the
potential to solve the problem of lack of spectrum space, but can also enable
novel application. The visible light spectrum is unused; it's not regulated,
and can be used for communication at very high speeds. Wi-Fi and many other
radiation types are bad for sensitive areas. Like those surrounding power
plants. But power plants need fast, inter-connected data systems to monitor
things like demand, grid integrity and (in nuclear plants) core temperature.
The savings from proper monitoring at a single power plant can add up to
hundreds of thousands of dollars. Li-Fi could offer safe, abundant connectivity
for all areas of these sensitive locations. Not only would this save money
related to currently implemented solutions, but the draw on a power plant’s own
reserves could be lessened if they haven’t yet converted to LED lighting.
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. 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 isn’t allowed such as aircraft or hospitals. One of the shortcomings however is that it only work in direct line of sight. There are so many applications of this technology and even this technology is used in developed country. Rest of large information you can find out on internet. I think it’s enough to understand the basic of this technology.
Thanks
Parveen Kumar Sahrawat
