Researchers have developed a new technology that delivers ultra high-speed Wi-Fi via light beams.
In the future, this new technology will allow Internet users to download a single movie in the blink of an eye.
Oxford University researchers published in the IEEE Photonics Technology Letters just how exactly they were able to develop a light-fidelity wireless networking technology that can send and receive information through the air in as much as 100 Gigabits per second (Gbps). For the time being, Internet users will have to make do with the current state-of-the-art Wi-Fi 802.11ac, which allows for 7 Gbps to 10 Gbps of data transfer.
In the United States, most people are lucky if they have access to 1 Gbps of Internet connection currently offered by a few providers in a smattering of locations. However, if the Li-Fi technology pushes through, Internet users of the future could potentially enjoy as much as 3 Terabits per second (Tbps), which is a whole lot of data.
High-speed fiber optic cables used to deliver 1 Gbps of Internet connection already use light to transmit data across the network by using internal reflection to guide the light along the way. This assures no data is lost during transmission. The problem, however, lies in using light to transmit data through the air to a computer.
Addressing this problem, the researchers installed a base station into the room's ceiling, which would send and receive data to and from the computer and the Internet.
By fitting the transmitter and receiver with holographic beam steering technology, the researchers then created programmable diffraction grating using an array of liquid crystals that would beam the light in a certain direction.
Dominic O'Brien, lead researcher and photonics engineer at Oxford University, says the technology works similarly to projectors.
The technology is not without its limitations. First, because light does not pass through opaque objects, Li-Fi can only work within line of sight. The researchers say the computer must be in a fixed position for now. Also, the speed is also dependent on the receiver's field of view. For instance, with a 60-degree field of view, the researchers were able to transmit six wavelengths of 37.4 Gbps each, for an aggregate bandwidth of 224 Gbps. When the field of view was narrowed down to 36 degrees, the researchers transmitted only three wavelengths for an aggregate bandwidth of 112 Gbps.
O'Brien says the researchers are working to incorporate tracking technology into the system so that the light can locate the computer wherever it is placed in a room.
LiFi is an emerging technology that Harold Haas, one of its pioneers, says has the potential to be a more attractive alternative to Wi-Fi in localized areas, since light cannot pass through walls. Haas says he sees a future where, instead of installing homes and offices with 14 billion lightbulbs, we can install 14 billion LiFis.
"All we need to do is fit a small microchip to every personal illumination device and this would then combine two basic functionalities: illumination and wireless data," Haas said (video) in a TED talk on LiFi.
However, while most LiFi technologies rely on visible light, the researchers used infrared light at 1550 nm, which is unseen by the naked eye.
