Most startups dream of someday making their mark on a single industry. If all goes according to plan, PureLiFi will stir up two industries at once. As the world’s leading Li-Fi startup, the company has developed technology that delivers high-speed wireless Internet service through the LED lights found in homes and offices.
This week at Mobile World Congress, an annual gathering for the smartphone industry held this year in Barcelona, PureLiFi revealed a sleek new integrated Li-Fi luminaire and spoke to IEEE Spectrum about its plans to expand commercial pilots in the months ahead. The company’s leaders also opened up about their eagerness to ditch the Li-Fi–enabled USB dongle they debuted at the same trade show just last year.
PureLiFi, which is based in Edinburgh, has developed a technique that uses flashes of light to transmit information, instead of encoding data on a radio signal that is broadcast over the air, as done by today’s Wi-Fi routers. The flashes are so fast that they are not noticeable to the human eye. (For more on how Li-Fi works, read this story by IEEE’s The Institute.)
But so far, people can only access PureLiFi’s technology by plugging in a dongle to their laptop, which many users find inconvenient. Last year at MWC, PureLiFi revealed the world’s first Li-Fi USB dongle, called LiFi-X. The credit-card–sized dongle contains a photoreceptor that receives a signal from a Li-Fi–enabled light, and an infrared transmitter to send data back.
Based on what the PureLiFi team shared, connecting to Li-Fi in 2017 should be less clunky and more convenient. The company says this year, it will shrink its dongle to half of its current size and 40 percent of its weight.
Of course, the dongle is only part of the equation. For this year’s show, PureLiFi unveiled a new luminaire that integrates Li-Fi modulation components into a black ring designed to encircle an LED light. The ring lays flush with the ceiling and makes Li-Fi-enabled LEDs virtually indistinguishable from any other lights in a home or office.
Previously, the company’s only Li-Fi access point was a white box, roughly the size of a smartphone, that had to be mounted to the ceiling next to an LED light.
In a demo on Monday, Nikola Serafimovski, director of business strategy for PureLiFi, plugged the LiFi-X dongle into a laptop and connected to the Li-Fi network by selecting it on his screen, just as a user might choose their WiFi network. He then began to play a YouTube video and walked from below one light fixture equipped with the company’s original access point to one featuring the new integrated luminaire, demonstrating that the technology was capable of a seamless handoff as a user moves around a room or building. He placed his thumb over the dongle’s receiver to momentarily block the connection, proving it was live.
Speed is one of the reasons that so many companies are intrigued by Li-Fi. When Harald Haas, founder and Chief Science Officer of PureLiFi and a professor at University of Edinburgh, first began working on Li-Fi, he achieved a peak data rate of 10 megabits per second with some basic modulation. Now, with the help of new techniques, PureLiFi can achieve peak rates of 15 gigabits per second.
One of those techniques is wavelength-division multiplexing, which allows the company to separately encode data on the red, green, and blue channels within a white LED. With it, Haas says 100 Gbps rates are on the horizon.
In real-world settings, the company’s products deliver data rates of about 45 Mbps for both uploads and downloads. For comparison, the average broadband Internet connection in the U.S. offers download speeds of 54 Mbps, while mobile Internet service provides about 20 Mbps. Upload speeds are significantly slower.
There are some special considerations that come with using Li-Fi, such as the fact that light doesn’t penetrate walls, so every room in a house would need a Li-Fi–enabled lighting fixture. However, PureLiFi likes to pitch this factor as a feature that also keeps users’ data secure, since communications are inaccessible to anyone who is not in the same room.
At least in the eyes of Alistair Banham, CEO of PureLiFi, the company’s early trial participants have so far responded positively to the technology. “The major feedback is that they love the security of information,” he says. “The feedback on the speed has been very, very positive.”
However, there is one area where those users have told Banham that there is clearly room for improvement. “Obviously, the goal is to go beyond the dongles, and they understand that,” he says. “Everyone would like to have it integrated into their devices.”
Banham and Haas know that Li-Fi will not be widely adopted until it is integrated into the chipsets of laptops, tablets, and smartphones. In the meantime, Banham points out that both Wi-Fi and Bluetooth also started out with dongles, and that it took nearly a decade for those technologies to move to chipsets and become widely adopted. “I think we'll be much faster,” he says.
It’s not clear whether PureLiFi would manufacture a Li-Fi chipset itself, or work with a partner to do so, and Haas couldn’t comment on the company’s plans. The company is actively working with other stakeholders to develop standards for LiFi that ensure consistent performance across devices, just like the standards that exist for Wi-Fi.
Haas says the world needs to put Li-Fi in its chipsets because there is a scarcity of bandwidth available for wireless devices, and pesky interference when too many devices operate at once. “It’s inevitable that we have to go to light as a wireless means of communication,” Haas says.
Ultimately, Haas doesn’t view Li-Fi as a replacement for other wireless technologies such as 5G for cellular networks or Wi-Fi. Instead, he thinks Li-Fi will work hand-in-hand with existing technologies to provide the most bandwidth to users, rather than compete with them.
He does hope the recent commercial pilots will help them overcome some common misconceptions about Li-Fi. Haas says many people still wonder if Li-Fi works in the presence of sunlight (it does) or think it will only work if the transmitter and receiver have a clear line of sight to one another. In reality, PureLiFi has found that reflections off of walls and floors deliver perfectly adequate data rates.
Haas has now spent the past 15 years working on Li-Fi, which began as a “curiosity-driven project” in his lab. He’s not at all surprised that he is still waiting to see it be integrated into mainstream products. “For me, it was always clear, it will not be an easy road,” he says.