The installation of your next home network might be as easy as screwing in a light bulb. If some engineers have their way, we’ll soon be transmitting data—and even audio and video—via energy-saving LED lights that modulate, rapidly turning on and off much faster that the human eye can detect.
The technology is called visual light communications (VLC), and can potentially transmit data at Ethernet speeds of 100 megabits per second (Mbps). The LED rapidly flashes the data to a receiver that decodes it to information. With VLC, you could download helpful information from an LED sign to your smart phone, for example. Or a car’s brake lights could transmit a signal to the car behind it to brake automatically if it’s approaching too fast. Samsung is even looking to use LED backlights in LCD TVs to transmit product information, web sites and other data to viewers, though a company spokesman says the technology is a couple of years away.
Proponents of VLC say it has many advantages, such as data capacity (much like fiber-optic wiring) and that it doesn’t interfere with RF (radio frequency) used for wireless networks. VLC is not intended as a replacement for Ethernet or WiFi or mesh networks like ZigBee, but as something that can be used where and when RF can’t be used, like in hospitals and on airplanes.
VLC is also point-to-multipoint, which means separate data streams can be fed to each device.
And wherever you have LED lamps, you have a potential network. “This opens up a whole different set of possibilities,” says Bob Heile, chairman of the ZigBee Alliance. “People are going to do some interesting stuff with this.”
Heile says he’s experienced sound transmitted via VLC, using RGB (red, green and blue) LEDs, in which the separate colors transmitted audio from individual instruments. Others envision indoor lighting fixtures communicating with each other to normalize colors and provide uniformity. LED lamps at supermarkets could be used to provide shoppers with information about products and to track shopping behavior.
Heile is also the chair of the IEEE Standard Association’s 802.15 wireless personal area networking (WPAN) standards group, which is working on a standard (802.15.7) for visible light communications. Heile says the final approval of a standard could come by March 2011, with products available shortly thereafter.
Don’t look for speeds like 100Mbps right away, though, cautions Heile, as early products are likely to have lower data rates.
But, oh, the potential.
Body Area Networks
We’ll also soon be seeing sensors that can be placed on or in your body—both for medical and entertainment purposes. The world of digital home health care could take off with sensors that report a patient’s vital signs and other information to a doctor or hospital.
These body area networks (BANs) could include wearable or implanted glucose sensors, capsules for drug delivery, remote control of medical devices, retina implants, and what Heile calls Video Gatorade—a swallowed camera that can take high-def pictures of your insides.
Body area networks can also be used for the seamless exchange of information, from just a handshake, for instance.
Gaming could become even more realistic when body sensors are involved—like Wii games on steroids. Care to pair that with 3DTV? You know it will happen.
A standard for body area networks is also being developed (IEEE 802.15.6) and could be approved some time next year. “Some of these devices exist today, but they lack a really effective communications network,” says Heile. That’s what the IEEE standard aims to provide.
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Steven Castle is Electronic House's managing editor. he has been writing about consumer electronics, homes and energy efficiency topics for two decades. He is also the co-founder of GreenTech Advocates