Is This The Year When Li-Fi Will Take Off?
Over the last few years, scientists and engineers have been working on a new technology which could become as transformative as the internet itself. Light Fidelity is on the cusp of revolutionizing data distribution – eliminating wifi, rendering 5G largely redundant, and providing secure data streams at unimaginable speeds.
Light Fidelity operates on similar principles to today’s wifi, but is distributed across higher frequency (shorter wavelength) bands. These are far less congested than the 2.4GHz Industrial, Scientific and Medical band, used today by numerous electromechanical devices. It’s been calculated that the Li-Fi frequency spectrum is 2,600 times larger than the existing RF spectrum, and adopting it should effectively eliminate interference or packet loss.
Tripping the light fantastic
Remarkably, the infrastructure for distributing Li-Fi is already with us. Any light emitting diode is capable of transmitting digital data since LEDs are either off or on. This binary state matches the digital data underpinning everything we do on computers – and over the internet. Turning a light source on and off thousands of times per second could provide a constant stream of digital data to a photodiode receiver. The human eye wouldn’t even detect any flickering at this speed.
The idea of distributing internet content through light bulbs might sound like a science fiction storyline, but Li-Fi is already being tested in proof of concept trials around the world. It’s been established that any LED is a viable data source, from electrical appliance standby lights to car taillights and streetlamps. This raises the intriguing prospect of a constant internet connection both indoors and outdoors, with devices seamlessly switching between available arcs of light.
Even so, the most common distribution source is expected to be ceiling-mounted LED spotlights. These have gradually replaced traditional bulbs and fluorescent strip lighting in homes and workplaces across the world. Scientists are currently developing LED bulbs capable of receiving data as well as distributing it, to support data uploads for activities like video calls and online gaming.
Into the darkness
Li-Fi requires line-of-sight between a data point and a recipient device, but this potential drawback actually brings a number of advantages. Firstly, it prevents eavesdropping. Someone outside your home couldn’t monitor your internet activity as they could over wifi, because light isn’t porous and can’t penetrate walls or thick curtains. Secondly, high-frequency data transfers don’t generate electromechanical interference, making Li-Fi safe for use on planes or in hospitals. Thirdly, tracking a device’s movement from one light bulb to the next could underpin precise location services, such as augmented reality displays for individual areas in a store. Today’s Wi-Fi cell tower triangulation would struggle to place you in the correct store, let alone the right aisle.
However, the biggest benefit offered by using this new technology is the amount of bandwidth it will unlock. An estimated 125 billion Internet of Things devices are expected to be online by 2030, and RF frequencies are creaking under the strain. Experts predict the RF spectrum will be absolutely full in 15 years’ time. That won’t be the case with Li-Fi, which offers 200 THz of available bandwidth. Nor does the light have to be dazzling – a single photon can facilitate data transfer, so light sources could be almost undetectably faint while still working optimally.
Setting the standard
The world’s biggest electrical and technology firms are already developing an industry standard for Li-Fi – 802.11bb. Once it goes live in 2021, manufacturers will be able to design devices capable of receiving data from almost any LED light source. Having dependable access to ultra-fast, interference-free and highly secure internet streams won’t be the stuff of science fiction for much longer…