An increasingly connected world celebrated Wi-Fi Day on Thursday, mindful that it’s actually Li-Fi that’s making the waves.
Light fidelity, which uses light waves instead of radio waves to provide an internet connection, is promising to make significant inroads by reducing network congestion around the globe, including in India.
For instance, Wipro Lighting, a unit of Wipro’s consumer care business, has begun offering this technology to Indian customers in partnership with PureLifi Scotland. “We are offering LiFi (data through light) solutions for significantly greater security and safety and ultra fast data transmission rates to deliver unprecedented low latency and reliability. This is to complement and enhance existing cellular and Wi-Fi networks," said Anuj Dhir, vice-president and business head of Wipro Lighting.
In August 2018, PureLiFi deployed its Li-Fi solutions at Kyle Academy secondary school in Ayr, Scotland. The project was conducted in collaboration with Edinburgh University and is being overseen by the Scottish Futures Trust, which supports the Scottish government’s digital strategy. PureLiFi and the LiFi Research and Development Centre at Edinburgh University provided the resources for the execution of the pilot with hands-on support and subsequent testing.
The installation of PureLiFi’s LiFi-XC system comprised eight LiFi-enabled LED light bulbs in the ceiling. Students were given access to LiFi-XC stations that plug into their laptops enabling high-speed connectivity through the lights. Kyle Academy was the first school globally to pilot the technology in the classroom.
This June, at the International Paris Air Show in Le Bourget, Air France, Latecoere and Ubisoft showcased their Li-Fi technology using light to transmit data and ran an in-flight video game tournament showcasing this technology.
On 19 June, Signify announced that the launch of a new range of Li-Fi systems that includes the world’s fastest and most reliable Li-Fi systems commercially available. The range, branded Trulifi, leverages existing and future professional luminaires. Instead of using radio signals (such as Wi-Fi, 4G/5G, Bluetooth, etc.), Trulifi uses light waves to enable highly reliable, secure two-way wireless communications at speeds far above most conventional workplace wireless technologies.
The term Li-Fi was coined by Prof. Harald Haas, founder and chief scientist of pureLiFi, and also a professor of mobile communications at Edinburgh University. Li-Fi is a category of Optical Wireless Communications (OWC), which includes infrared and ultra-violet communications as well as visible light. However, Li-Fi is unique in that the same light energy used for illumination may also be used for communication.
LiFi comprises multiple light bulbs to form a wireless network. When an electrical current is applied to a LED light bulb, a stream of light (photons) is emitted from the bulb. As explained on the Purli-Fi website, LED bulbs are semiconductor devices, which means that the brightness of the light flowing through them can be changed at extremely high speeds. This allows one to send a signal by modulating the light at different rates. The signal can then be received by a detector which interprets the changes in light intensity (the signal) as data. The intensity modulation cannot be seen by the human eye, and thus communication is just as seamless as other radio systems, allowing the users to be connected where there is Li-Fi enabled light. Using this technique, data can be transmitted from an LED light bulb at high speeds.
Signify’s Trulifi, for instance, uses optical wireless transceiver technology built, or retrofitted, into Philips Luminaires, which means customers do not have to rip and replace their existing lighting infrastructure. The new range, according to a company statement, provides wireless connectivity at speeds up to 150 megabits per second (mbps) over large spaces such as meeting rooms and office floors, and allows for a seamless handover between each Trulifi-enabled luminaire. The speed is fast enough to stream simultaneously 30 1080p HDTV movies. A USB-access key, plugged into a laptop, is needed to receive the LiFi signal and acts as an emitter to send data back to the luminaire.
“Trulifi underlines our strategy to unlock the potential of light to address new high-growth markets," said Olivia Qiu, Chief Innovation Officer at Signify.
There are compelling reasons to use Li-Fi in conjunction with Wi-Fi. For one, with the increasing number of internet-connected devices in classrooms, installing Li-Fi alongside Wi-Fi can provide additional bandwidth to reduce network congestion, enabling students to stream educational videos and download resources with seamless connectivity. Second, Li-Fi has the capability to support big data, and technologies like augmented reality, virtual reality, machine learning, artificial intelligence, according to Prof. Haas.
Moreover, while there is 300 gigahertz of radio spectrum, there is 300 terahertz of visible light spectrum. If you add infrared spectrum to the visible light spectrum, it will be 2,600 times larger than the entire radio spectrum, Haas said at Mint’s flagship technology conference in 2017, adding that this spectrum is free.