Let There Be LiFi: Extraordinary Innovations in Visible Light Communications
Where light exists, life exists. And data communication. Discover the newest channel in communications.
Dec 7, 2021
Where light exists, life exists. And data communication.
Since the dawn of civilization, humanity has been on a quest to communicate. In antiquity, distant communities relied on fiery hilltop beacons for signaling. In tempestuous seas, offshore sailors sought out beams of light from the coastline. If there was line-of-sight, there was a means for communication. With the discovery of electricity, communication beyond the line-of-sight became possible. The farthest reaches of the globe can be accessed instantly and directly. Yet, our quest for data transmission is still ongoing.
WiFi – or wireless fidelity – allows us to connect to the internet without a physical tether. Using radio waves for transmission, a device can be located up to 50 meters radius from an access point, and still receive a signal. However, because radio frequencies have a limited bandwidth, it’s possible to get interference and have a disrupted connection. Additionally, because of its omnidirectional span, WiFi is inherently vulnerable. The digital stream can be hacked and compromised.
Enter Visible Light Communications (VLC), more popularly referred to as LiFi. This form of transmission utilizes light waves as the conduit of data. Light travels 100 times faster than radio. The light spectrum is also massively greater than the radio spectrum with frequencies covering from 430,000 to 770,000 GHz compared with the 3 Hz to 3,000 GHz of radio.
LiFi’s limitation—that there must be line-of-sight between transmitter and receiver—is inherently a benefit, too, since that makes LiFi extremely difficult to hack. LiFi is literally blocked by physical walls and can therefore be contained within a defined space. This makes LiFi incomparably more secure than WiFi. In fact, the early adopters of LiFi have been military applications.
Currently, the major barrier to widespread LiFi adoption are incompatible devices. Do you remember back in the 2000s when your laptop was unable to connect to wireless internet unless you plugged in a WiFi dongle? That is currently the case with LiFi. There are indeed luminaires on the market with the capability of transmitting data to your device, but for the most part the market hasn’t yet produced phones or computers with integrated receivers. Instead, as we did back in 2000s, we can purchase a USB LiFi dongle and get connected.
Ingenious LiFi Applications
LiFi technology is rapidly entering our everyday lives. Here are some real-world applications of smart lighting:
An Air France flight piloted in-flight entertainment using LiFi. The lights above the passenger seats streamed data for the gaming console. Passengers successfully competed in a gaming tournament, which typically requires fast and reliable internet speeds. Aside for the entertainment benefit, replacing copper lighting cables with fiber optic cables reduced the overall weight of the plane, thus reducing its fuel consumption.
In this VLC application, shoppers at MediaMarkt, a supermarket in Germany, initiated a connection to the store’s lighting system through the MediaMarkt app. The store’s lighting grid transmitted an imperceptible signal that was received by the shoppers’ smartphone camera. Using this data stream, the app precisely determined the shoppers’ locations and then displayed relevant product coupons and product wayfinding for a hyper-personalized shopping experience.
While not a true LiFi system in the sense of streaming data outwards, the lighting system at The Edge – a state-of-the-art and sustainable office building in Amsterdam – is powered by ethernet rather than copper cabling. Sensor-rich, the smart luminaires capture and transmit real-time room occupancy data which then integrates with the building’s ventilation and heating systems.
And there’s more to come…
The possibilities are mind-blowing. Streetlights can provide free internet access to passersby. Vehicles can communicate with each other through their headlights. Hospitals can create a smart lighting grid that tracks and geo-positions moveable assets such as wheelchairs. Museums can develop immersive and seamless visitor experiences using headsets that narrate information based on visitor location.
Who’s Who in the World of LiFi
Interestingly, the hub of research and development for LiFi technology is centered in Europe. At the forefront is the LiFi Research and Development Centre based out of the University of Strathclyde, Scotland. Directed by LiFi pioneer, Professor Harald Haas, the institution funnels go-to-market technologies through its acclaimed technology company PureLiFi. In the United States, LVX System has been working in collaboration with NASA to develop applications of LiFi technology in aeronautics.
Getac is a global supplier of rugged computing products for military and heavy industrial usage. In partnership with PureLifi, they have built the world’s first tablet with integrated LiFi. Users could be situated in an underwater laboratory – which is impervious to radio waves – or in a classified bunker and have wireless access to the internet.
LiFi is steadily gaining traction in the mass market. Philips Signify is the global leader in lighting. Interact is their IoT lighting division and includes a suite of software solutions to manage connected lighting. Of note are two other European manufacturers, Oldecomm and Lucibel, who offer a LiFi product portfolio including luminaires, USB keys and access points. Check out their websites (in English!) for more insights about LiFi.