Li-Fi Technology

-

 

Introduction To Li-Fi Technology:

Unlike Wi-Fi that uses radio wave, Li-Fi is a wireless communication technology that uses light waves to provide an internet connection. 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.

This technology uses a part of the electromagnetic spectrum that is still not greatly utilized- The Visible Spectrum. It is possible to encode data in the light by varying the rate at which the LEDs flicker on and off to give different strings of 1s and 0s. The LED intensity is modulated so rapidly that human eyes cannot notice, so the output appears constant.

More sophisticated techniques could dramatically increase VLC (Visible Light Communication) data rates. Teams at the University of Oxford and the University of Edinburgh are focusing on parallel data transmission using arrays of LEDs, where each LED transmits a different data stream. Other groups are using mixtures of red, green and blue LEDs to alter the light's frequency, with each frequency encoding a different data channel.

How it works?




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.


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.


Conclusion:

Despite being a much speedier internet technology as compared to wi-fi, Li-Fi implementations are yet to make any dent in India. It allows for much faster data transfer and is considered more secure than Wi-Fi. Given that the visible light spectrum is 10,000 times larger than radio waves and hence Li-Fi’s speed can be 100 times faster than Wi-Fi.

Wi-Fi spectrum is limited, but when we use light, the spectrum increases. Data transfer is much faster and data privacy is much higher in case of Li-Fi. The only disadvantage is that, when there is no light, we can’t get the data.  

 

Popular posts from this blog

Brain Computer Interface (BCI)

-
Image
  Introduction To Brain Computer Interface (BCI): Brain-computer interface (BCI) is a collaboration between a brain and a device that enables signals from the brain to direct some external activity, such as control of a cursor or a prosthetic limb the interface enables the direct communications pathway between the brain and object to be controlled. Technology has made it possible to make use of computers as a replacement for the brain. Many kinds of research are going on to reduce the human work. The world is marching towards the automation in order to reduce the complexity in the work, speed up the process and at the same time to provide a relaxed life to all mankind. Some of the technologies involving human brain are blue brain project , the blue eyes technologies . A Brain-computer interface (BCI) provides a new communication channel between the human brain and the computer. The 100 billion neurons communicate via minute electro-chemical impulses, shifting patterns sparking lik
Read more

Humanoid Robots

-
Image
                                         Humanoid Robots A Humanoid may be defined as something that resembles or looks like a human and having characteristics like opposable thumb, ability to walk in upright position etc. These robots are called Humanoid Robots or may be simply “Humanoids”. A humanoid robot is a robot which has a similar shape as that of a human body. In general, a humanoid robot has a torso, a head, two arms, and two legs. These robots vary depending upon the material they are made of and the design. Generally, humanoid robots come in three variations small sized humanoids, medium sized humanoids, and large sized Humanoids. Some humanoids may also have a face, eyes, mouth and are categorized as male humanoids and female humanoids. The purpose of such robots may vary depending upon its bio-mechanics, functional capacity, production cost and complexity involved.  Features of Humanoid Robots : The characteristics features of Humanoid includes: •       Self-mainten
Read more