LiFi Connectivity is evolving

byLatest technology information with real review -الأحد, يوليو 04, 2021

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Li-Fi :-

Li-Fi (also written as LiFi) is a wireless communication technology which utilizes light to transmit data and position between devices. The term was first introduced by Harald Haas during a 2011 TEDGlobal talk in Edinburgh.

In terms of its end use, the technology is similar to Wi-Fi — the key technical difference being that Wi-Fi uses radio frequency to induce a voltage in an antenna to transmit data, whereas Li-Fi uses the modulation of light intensity to transmit data. Li-Fi can theoretically transmit at speeds of up to 100 Gbit/s. Li-Fi's ability to safely function in areas otherwise susceptible to electromagnetic interference (e.g. aircraft cabins, hospitals, military) is an advantage. The technology is being developed by several organizations across the globe.

• Visible light communications :-

Visible light communications (VLC) works by switching the current to the LEDs off and on at a very high speed, too quick to be noticed by the human eye, thus, it does not present any flickering. Although Li-Fi LEDs would have to be kept on to transmit data, they could be dimmed to below human visibility while still emitting enough light to carry data. This is also a major bottleneck of the technology when based on the visible spectrum, as it is restricted to the illumination purpose and not ideally adjusted to a mobile communication purpose. Technologies that allow roaming between various Li-Fi cells, also known as handover, may allow to seamlessly transition between Li-Fi.

The light waves cannot penetrate walls which translates to a much shorter range, and a lower hacking potential, relative to Wi-Fi. Direct line of sight is not necessary for Li-Fi to transmit a signal; light reflected off walls can achieve 70 Mbit/s.

• WHAT IS LIFI TECHNOLOGY Full Form ? :-

LiFi (light fidelity) is a bidirectional wireless system that transmits data via LED or infrared light. It was first unveiled in 2011 and, unlike wifi, which uses radio frequency, LiFi technology only needs a light source with a chip to transmit an internet signal through light waves.

This is an extraordinary advance over today's wireless networks. LiFi multiplies the speed and bandwidth of wifi, 3G and 4G. The latter have a limited capacity and become saturated when the number of users surfing increases, causing them to crash, reducing speeds and even interrupting the connection.

With LiFi, however, its band frequency of 200,000 GHz, versus the maximum 5 GHz of the wifi, is 100 times faster and can transmit much more information per second.

• LI-FI VS WI-FI :-

When looking at the comparisons between WiFi and LiFi, it would be very difficult to choose one over the other as both have their own merits – and their own disadvantages. That is why a different mind-set needs to be adopted and look at these pieces of technology in a different way.

A big misconception about LiFi systems is that it was created to replace WiFi altogether. Considering that most of the existing infrastructure has already been built to accommodate RF technology, it would be very costly and tedious to replace all of that infrastructure to give way to a newer technology. For this reason, LiFi needs to be looked at as a complementary technology that aims to improve the performance of the existing technology and provide relief to the already congested radio spectrum used to provide WiFi connections.

• LI-FI Router :-

LiFi is like WiFi — except instead of using a router to transmit data, you’re using an LED light bulb to send messages over the visible light spectrum.

Because it runs on light waves from common household LED bulbs, LiFi technology operates the way light does. Visible light has a much wider bandwidth than WiFi, meaning that LiFi-enabled devices can send and receive huge volumes at extremely high speeds.

• Advantages of LiFi :-

There are many different advantages offered by using LiFi. One of its biggest benefits come with its efficiency. Since LiFi makes use of VLC technology, which in turn makes use of highly-efficient LED bulbs, users are able to enjoy lower costs in terms of energy consumption. Additionally, they only require working LED lights, which are already available within most households and other establishments, allowing for additional savings in terms of installation costs.

Another big advantage of LiFi is that the usage of light allows LiFi connections to occur almost instantaneously because light travels at extremely fast speeds. This results in faster transmission of data and faster internet connections – about 100 times faster than speeds achievable by WiFi.

Because there are already 14 billion light bulbs all over the entire world, its availability is never in question as there can be as many LiFi networks available as there are light bulbs.

Lastly, the nature of visible light is that it cannot penetrate opaque walls. This means that as long as rooms are covered by opaque walls, light is confined within the space in which it is shone, thereby confining the connection to the space in which it is shone. This prevents unauthorized access to the LiFi connection, adding another layer of security to the network.

• Disadvantages of LiFi :-

There can be many disadvantages to LiFi, as well. Its biggest drawback comes in the form of infrastructure (or lack, thereof). Since LiFi technology is a relatively new concept and is currently in its introductory stage, the infrastructure necessary to implement the technology in a large enough scale is still virtually non-existent. This means that plenty of time is still required before the general public can enjoy LiFi technology.

Another disadvantage is that the light source will need to be constantly turned on in order to provide network access. This problem can be solved by dimming the light enough to levels that the human eye can perceive as turned off, but are actually still on. In cases where dimming the light is out of the question, however, this could be a problem.

Another perceived disadvantage of LiFi connections is that because it relies on light to transmit data, it becomes highly susceptible to outside interference. Photodiodes are able to pick up light from competing sources of light such as sunlight and other forms of illumination. This could potentially create noise within the receiver and cause disruptions to the network. In most LiFi systems, an optical filter has been installed on photodiode devices in order to filter noise so that the receiver can only pick up signals coming from the transmitter.

Lastly, users are rendered immobile when using LiFi systems due to the limited range of the signal given off by light bulbs. This is, of course, countered by installing multiple LiFi systems within large spaces, creating as many connections as there are light bulbs.

• Li-fi in INDIA :-

AHMEDABAD: In the first step towards creating smart villages in Gujarat, an Ahmedabad startup has powered up two villages with high-speed internet using LiFi-based technology. Akrund and Navanagar villages in Aravalli district of Gujarat have become India’s first smart villages with LiFi-based internet connectivity.

With this facility from the startup, Nav Wireless Technology, schools, hospitals, post offices, and government offices in these two villages will get faster and safer internet connection through existing electricity lines.

LiFi technology involves transmitting data with a light beam spectrum through open space in outdoor and indoor environments. LiFi systems provide ultra-fast data connections, and are especially useful in urban areas where radio spectra are congested, and are also handy in rural areas where fibre-optic cables or networks are not reachable.

The company has invested Rs 20 lakh for executing the project in these two villages. Hardik Soni, co-founder and CTO of Nav Wireless Technologies Pvt Limited, said: “We are proud to bring this technological revolution to our home state of Gujarat.” Soni added: “Nav Wireless has extended Gujarat Fibre Grid Network’s fibre internet connectivity from Akrund gram panchayat building to Navanagar primary school, which is at the distance of 1.5km, with LiFi wireless optical communication.”

Soni went on to say: “We had also implemented Hybrid Microwave LiFi-enabled LED lights in schools, hospitals and in post office rooms over the existing power lines of the buildings.”

The startup has collaborated with BharatNet for implementing similar technology in about 6,000 more villages of Gujarat. This will be achieved by the end of the calendar year 2022. Funds worth Rs 500 crore will be allocated for the project.