LiFi: the Latest Technology
We are familiarized with the use of Wi-Fi, which allows electronic devices to connect to the internet. But, what is Li-Fi technology? Li-Fi is quite similar to Wi-Fi technology. While the difference between Wi-Fi and Li-Fi is that Wi-Fi uses radio waves for information transmission; whereas, Li-Fi uses the light waves.
Li-Fi is not a replacement of Wi-Fi technology, but it is a companion that is being prepared to blow existing Wi-Fi connections with its offered speeds of up to 1Gbps. Li-Fi is a high-speed, secure, bidirectional, fully-connected, and completely-networked wireless communication technology that operates between 380 nm to 780 nm optical ranges.
Working of Li-Fi Technology:
Li-Fi technology consists of application specific combinations of light transmitters, light receiver, efficient computational algorithms and networking capabilities. This technology is based upon the ideology of data transmission through LED light. Li-Fi uses transceiver-fitted LED lamps that can light a room, as well as transmit and receive information. It works on one simple principle. The LED is turned “on and off” at such a high speed that it is not visible to human eye.
This ribbon of “on and off” signals is interpreted to create binary streams of 0 and 1. The working procedure is very simple. If the light is on, then digital 1 is transmitted. If it is off, then digital 0 is transmitted. The LEDs can be switched on and off very quickly that gives adequate opportunities for transmitting data. The signals are received by the photo-detector, which converts them back into the original data.
Applications of Li-Fi Technology:
Li-Fi technology has several applications. Let’s review some of them:
- Use at educational institutions to get faster internet speed
- Use in operation theatres for radioactive operations, where it is safe to be used in place of Wi-Fi that uses Radio waves
- Use in aircrafts as it would not interfere with the navigational systems of the pilots unlike Wi-Fi
- Use in military operations where Wi-Fi completely fails to operate
- Use at places of disaster for disaster management
- Use in sensitive areas where other transmission medium can be hazardous.
Li-Fi vs. Wi-Fi: a Complete Comparison:
|Full Form||Light Fidelity||Wireless Fidelity|
|Operation||Data transmission through light||Data transmission through radio-waves|
|Interference||No interference issue||Interference issues from nearby routers.|
|Technology||Present IrDA compliant devices||WLAN 802. 11a/b/g/n/ac/ad standard compliant devices|
|Frequency of operation||10 thousand times frequency spectrum of the radio||2.4 GHz, 4.9 GHz and 5 GHz|
|Coverage distance||About 10 meters||About 32 meters, based on transmit power and antenna.|
|Data density||Works in high dense environment||Works in less dense environment|
|Privacy issues||More secure, as Li-Fi cannot pass through the walls||Not that secure, as signals cannot be blocked by walls|
|Topology||Uses point-to-point network topology||Uses point to multi-network topology|
|Components used||Photo-detector and lamp driver||Router and subscriber device|
|Band width||High due to broad spectrum||low|
|Bill of materials||High||Medium|
|Latency||In the order of microseconds||In the order of milliseconds|
Li-Fi LED: the Way LED Transmits Information:
In Li-Fi technology, the most important requirement is the light source as light is used the mode of transmission. It is necessary that the light source should possess the ability to be switched on and off repeatedly and quickly in very short intervals of time. Because of possessing this quality, LEDs are more suitable sources for Li-Fi as compared to fluorescent and incandescent lamps. LEDs are much more efficient, environment-friendly, flexible in design and improved spectrum performance.
Due to the change of energy levels in the semiconductor diode, LEDs emit light. The change in energy generates photons, out of which some are emitted as light. Wavelength of the emitted light depends upon the difference in energy levels and the type of semi-conductor material used in the making of LED chip. LEDs can bear up vibration shocks, frequent switching and extremes of environment because of their solid-state design. Also, because of this feature, they have long useful lives of more than 100,000 hours.
An LED is generally composed of a semiconductor diode chip mounted in the reflector cup of a lead frame. The lead frame is connected to electrical wires. This all is then encased in a solid epoxy lens. Changes in the data rate are very important in Li-Fi technology that is achieved with different sized LEDs. Micro-LEDs handle millions of variations in light intensity. A micro-LED can transmit 3.5 Gbps. The micro LED bulbs allow the light stream to be beamed in parallel thus transmitting huge amounts of data.
Hence, Li-Fi is the latest technology that makes use of light for the transmission of data through LEDs. It acts as a medium which delivers high-speed communication across all mobile networks. Li-Fi technology is quite like the Wi-Fi technology with only few differences. The main difference is that Li-Fi uses light for transmission whereas, Wi-Fi uses radio signals. Li-Fi provides a completely new layer of wireless connectivity within existing wireless networks. It supports multiuser access and enables roaming. Hence, Li-Fi is ideal for confined area and Wi-Fi is great for general wireless coverage within buildings.