Introducing an experimental modulator that enables laptops to transmit and receive high-bandwidth data via visible light!
Soon, getting an ultra-fast LAN bandwidth connection will be as simple as placing your laptop under floor lamps. Fraunhofer Institute is the latest research organization to bring visible light communications one step closer to commercialization.
What you see above are two laptops transmitting live videos to each other during the IFA 2011 trade show in Berlin (September 2-7, 2011). What’s unusual about this is that the video was sent via light emitted by LED bulb hanging above the booth ceiling. VLC, the principle behind Fraunhofer Institute’s invention, makes use of light spectrum instead of radio waves to send data.
How It Works
The left laptop feeds video to the LED bulb through an ethernet cable. The bulb sends modulated waves to the small box on the table, which has a photo sensor that converts the light into electrical impulses. The right laptop then reads the demodulated signals and play the video.
The right laptop sends its own video feed via the LED emitter in the box. The cylindrical receiver on the ceiling (beside the bulb) converts this LED light into electrical signals that can be read by the left laptop.
The result is a fast two-way wireless video streaming at 10 Mbits/s, made possible by the photo sensors and light sources on both the ceiling and the box. Now I think you’ll raise your glass with me to say that that’s a pretty neat bit of technology.
Solution to Bandwidth Scarcity?
With worldwide annual Internet traffic reaching 667 exabytes (that’s 667 quintillion bytes), radio bandwidth is increasingly becoming scarce. One possible solution is to use the abundant spectrum of light which is also an electromagnetic wave. The size of light spectrum is 10,000 more than radio waves’. Moreover, artificial light sources are available almost anywhere, making this new breed of optical Internet viable for mass consumption.
A part of the Omega Project of the EU government, Fraunhofer Institute’s invention converts LED waves into a medium that is more powerful than radio waves. The intensity of modern LED bulb’s output will not suffice for transferring huge data, but it can be increased by a process known as modulation. Imagine the power of LED-powered TV remote control being multiplied thousands of times. That’s the capacity needed to enable LED light waves to send huge data like Youtube video.
Skeptics question the viability of bidirectional VLC. Sure, the laptops were able to stream and receive HD video via amplified light waves, but it’s because the sources of light and the receivers were within a direct line of sight. But in the real world, how can a client, server, a wireless backhaul communicate with one another via optical Internet if they are separated hundreds of miles apart?
Light cannot pass through solid objects unlike radio waves, thus it cannot penetrate the roof and relay data to client computers or smartphones inside buildings. But overestimating or underestimating the potential applications of light-based wireless communication is an easy mistake at this point in time. Its future depends on the ability of engineers and application developers to address the technical limitations of using amplified light waves to communicate electronically.
The institute acknowledges that its VLC technology is not advanced enough to replace radio frequency. Yet the technology can complement existing WiFi/WLAN systems. VLC can help a lot in alleviating spectrum shortage by opening up light frequency for phone or Internet communications. There is an unmet demand for safe but efficient wireless communications in intensive care units, fire-prone industrial sites and ocean floors where radio waves are not safe or effective.
VLC has more to offer. Early this year, the institute set a new record by sending data via red-blue-green-white LED light at a speed of 800 megabits per second. The so-called “LiWi” set-up will also reduce if not eliminate wireless tapping. Fraunhofer Institute have no plan yet to commercialize the technology, but another VLC research project, led by Harald Haas, is expected to pave the way for the commercialization of VLC transmitter next year.
About Jakk: Jakk Ogden is the founder of Technology Blogged. 23, with a love for good writing, you'll find Jakk playing 'Drag Racing' on his Nexus 5 and rocking a pair of Grado headphones. If you love technology, be sure to subscribe to his feed for unique editorials. View author profile.