Crazy Crabby Life: LiFi: WiFi from Light

Introduction:

Switches, funny little things aren't they. Switch On and the appliance/ gadget/ device works and switch off to halt the machine from working!

What if one could get the Internet with a flip of a switch? That would be cool! Wouldn't it?

History of Wifi and advancements

Internet. Inter-net. Inter-net. It creates a non-tangible web due to connections over the world, connected through each other, by signal transmissions. While the signal transmissions are conducted by modems or devices that generate access to the World Wide Web. During the neonatal phases of the internet, everyone used to use an ethernet cable, where a cable has to plug onto the system that needs to gain access to the WWW.

Pic 1: The internet is a 'net' or a mesh or a web, created by the people who are connected via signal transductions between their devices

As the internet grew, with time, scientific advancements took place to replace the unconventional ethernet cable with a wireless connection of the system to the internet-a wire-less fidelity was thus in use and is prominently still in use; we all know it as Wi-Fi

Pic 2: Types of modems that serve the connection between the internet and the system, enabling the internet on a device

Wi-Fi is a mode of wireless communication that has revolutionized communication. In todays' day and age, WiFi comes across as a basic utility, everyone needs - from a kid for their homework to corporate leaders running their businesses. Heck! Even my boss and I need the connection to make this website, and thus this blog comes to life, not to mention thanks to your modem connection that helps you get this webpage from the internet and Wi-Fi hotspots are something we look forward to when we travel, out of our homes, offices, and travelling. It’s something that is in demand, and is served at Cafes, Restaurants, Inns, Flights, and Institutions even! That's mostly because they want to serve the public better and how! This facility makes sure our work can continue wherever we may be. From gaming to accessing work emails to sending reports, if you have the connection, nothing can stop you.

It's something everyone around the globe uses. Well, at least the first and second world countries have moderate access to it, and the rich people from the third world countries. It's sad, the internet is available for those with money only. But a switch? It's present in every household, for Fans, Lights, Air Plug points, etc. So what if a flip of a switch could generate WiFi for everyone?

Well, that possibility, isn't just a possibility; it's true. Really!!

So, I welcome you all to Li-Fi: Light Fidelity, utilizing Light as a medium for Wi-Fi. Wi-Fi from Light!

Light: The fastest thing in the universe, transmitting data!

Li-Fi :

Light Fidelity (Abbr: Li-Fi) is a wireless communication technology that utilizes light as a medium to transmit data between devices. The term was first introduced by Hsrsld Haas during his TEDGlobal talk in the year 2011. (Watch at: https://www.youtube.com/watch?v=NaoSp4NpkGg )

Light Fidelity was invented by Professor Harald Haas of the University of Edinburgh. The technology primarily comprises LEDs: Light Emitting Diodes that aid the transmission of data, by the minute flickering of the light waves, so minute that cannot be recorded by the naked eye. Even if a prominent light source occurs somewhere in the room, due to the absence of fluctuations of the light wave towards the photodetector, the photodetector wouldn't detect any data as such; because the system is designed so carefully that it would record the slightest fluctuations in the light being transmitted across.

Since the flickers and fluctuations are so minute, it doesn't hamper the utility of the light source in its primary form - to give light. So, now, the LEDs have dual functionality - Light Transmission and Data transmission

However, one must take note that the data collection is, and processing occurs in Binary Code, i.e. using 0s and 1s. The flickering or fluctuating light enables this.

Pic 3: Basic Concept

Source: https://www.ijser.org/researchpaper/A-Review-Paper-on-Li-Fi-Technology.pdf

This is how Professor Haas has managed to create a revolution and a new generation in light technology and the usage of the internet.

The main misconception about LiFi is that it won’t work with the lights off. However, Li-fi allows signals to be sent with light visibility down to 60 Lux. You may not be able to perceive that the lights are technically on, but they are. Indirect sunlight, Li-Fi can work through a filtering process that allows the receivers to only use signals from the LEDs and not from the sun.

Cause of Invention:

The innovation of this technology was brought to life to overcome these 4 hurdles :

Capacity
Efficiency
Availability
Security

Capacity - The amount of data transfer that is possible, would immensely increase a 100x almost, its also been recorded in 2015, that scientists in their labs were able to generate about 224 GB per second by the Li-Fi tech- which is HUGE!! and it could change everything about the way we use the internet

The average speed of the wi fi is 5.5 Mbps, while its peak goes up to 20Mbps. To take a leap from 20Mpbs to 100Gbps (average noted speed of data from Li-Fi tech) is revolutionizing everything on how we use the connection.

Efficiency - A base station tower, that utilizes radio waves for signal transduction uses so much energy, just to cool off the station, due to its working leading to the professional working capacity of 5% which is not so efficient in terms of energy consumption and savings. A LED bulb, can overcome that pretty easily.

Availability - We may have 100s of base stations, but more than base stations we have 100x more light sources - in car headlights, street lights, grocery shops, homes, offices, malls, and were not?!

Also when Professor had taken a deep look into the medium of signal transduction; Radio waves versus Visible Light, it was evident that the visible spectrum of the electromagnetic waves had a higher advantage by having a range of frequencies, i.e. data transmission would be possible in a wider range of frequencies that what Radio Waves has to offer.

Picture 4: A table of the frequencies and wavelengths of the EM spectra

source: http://labman.phys.utk.edu/phys222core/modules/m6/The%20EM%20spectrum.html

So, when one needs to think of availability, we have 10000x times more light sources (That probably just need fitting in place) and 10000x times the broad spectrum of the current EM wave type. There is an abundance of it, and we just need to learn to utilize it better and in an efficient way.

Pic 5: The VL spectrum is 10000x more than the range of the Radio spectrum

Source: https://www.ijser.org/researchpaper/A-Review-Paper-on-Li-Fi-Technology.pdf

Security: If I have classified data, a particular person wants, then they could hack my IP and gain access to it or hack my computer as a whole from somewhere else and data transmission would be possible because the wi fi is connected to the device at almost all times. But when I utilize a Li-Fi, data transmission can occur only where the light source is. And we know that light cannot travel across cement walls, so there is no way anyone else could bother getting their hands on my confidential data. Safe and Secure!

So, overcoming these problems may seem to be the merits of high order but the coin always has two sides. Some of the demerits are as follows:

1. The light has to be on at all times for data transmission to take place

2. There is no automatic method to stop the relay of the data transmission

3. Not to mention, the light pollution it causes.

4. Too much brightness from a light bulb could have potent threats to our eyes and overall health

5. Sightlines: Light cannot travel across barriers like walls, if the receiver is at one end, and you are at another with a wall in between, it adds on to making matters more difficult than it was to ease.

Applications:

Pic 6: Applications of Li-Fi in daily life, source: https://www.sciencealert.com/li-fi-tested-in-the-real-world-for-the-first-time-is-100-times-faster-than-wi-fi

With the wide use of data transmission these days, Li-Fi has proved to be more advantageous than the present-day technology of Wi-Fi. There are many fields where Wi-Fi and many technologies have failed but Li-Fi has proved its excellence.

Spectrum Relief: With the increase of cell phone users, the available bandwidth is insufficient and can lead to overloaded conditions. This problem can be solved by Li-Fi which uses the visible spectrum for communication.

Mobile Connectivity: Various devices such as Laptops, Mobile Phones, Tablets, and other devices can be interconnected directly by using Li-Fi. It gives very high data rates and also provides security.

Hazardous Environments: Li-Fi is a safe alternative as compared to radio waves as in radio waves electromagnetic interference takes place in environments such as mines and petrochemical plants.

Underwater Communication: To use radio frequency in underwater communication can be impractical due to strong signal absorption in water. Li-Fi provides an undue advantage in this case.

Thanks for Reading!

References:

https://www.ijser.org/researchpaper/A-Review-Paper-on-Li-Fi-Technology.pdf

https://en.wikipedia.org/wiki/Li-Fi

https://www.youtube.com/watch?v=NaoSp4NpkGg

https://www.elprocus.com/an-overview-of-li-fi-technology-and-its-benefits/

https://www.dailydot.com/debug/what-is-lifi/