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Researchers demonstrate how one payment card can transfer funds to another card by leveraging the existing wireless signals around them.
Ambient RF signals are both the power source and the communication medium.
Wearable technology seems to be a hot topic these days. Most of the major technology players have some form of wearable device in the works. Samsung is calling its product line, Galaxy Gear, which they say will encourage “a smarter life.” The hope is that Internet technology will move from being something that is some-what independent of us to something that is literally woven into our daily existence. From your shoes to your shirt, stove to your toilet, the future may be found in connecting every part of our lives. This is sometimes referred to as the "Internet of Things." Yet a fundamental problem still remains. How to power all these things?
Here's the question, would you use a “smart watch” if the battery only lasted 10 hours? For me the answer is probably no. But thanks to a new breakthrough from researchers at the University of Washington this problem may soon be a thing of the past.
The researchers have created a new wireless technology they describe as Ambient Backscatter. A UW website explains the concept further, “it transforms existing wireless signals into both a source of power and a communication medium. It enables two battery-free devices to communicate by backscattering existing wireless signals. Backscatter communication is orders of magnitude more power-efficient than traditional radio communication. Further, since it leverages the ambient RF signals that are already around us, it does not require a dedicated power infrastructure as in RFID.”
“It’s hopefully going to have applications in a number of areas including wearable computing, smart homes and self-sustaining sensor networks,” said lead researcher Shyam Gollakota, a UW assistant professor of computer science and engineering.
“Our devices form a network out of thin air,” said co-author Joshua Smith, a UW associate professor of computer science and engineering and of electrical engineering. “You can reflect these signals slightly to create a Morse code of communication between battery-free devices.”
The other researchers involved are David Wetherall, a UW professor of computer science and engineering, Vincent Liu, a doctoral student in computer science and engineering, and Aaron Parks and Vamsi Talla, both doctoral students in electrical engineering. The researchers published their results at the Association for Computing Machinery’s Special Interest Group on Data Communication 2013 conference in Hong Kong. They received the conference’s best-paper award for their research.
The UW posts describes the technology in greater detail:
The researchers tested the ambient backscatter technique with credit card-sized prototype devices placed within several feet of each other. Groups of the devices were tested in a variety of settings in the Seattle area, including inside an apartment building, on a street corner and on the top level of a parking garage. These locations ranged from less than half a mile away from a TV tower to about 6.5 miles away.
They found that the devices were able to communicate with each other, even the ones farthest from a TV tower. The receiving devices picked up a signal from their transmitting counterparts at a rate of 1 kilobit per second when up to 2.5 feet apart outdoors and 1.5 feet apart indoors. This is enough to send information such as a sensor reading, text messages and contact information. It’s also feasible to build this technology into devices that do rely on batteries, such as smartphones. It could be configured so that when the battery dies, the phone could still send text messages by leveraging power from an ambient TV signal.
The University of Washington researchers are not the only people looking at solving the problem of mobile / wireless power. The Wireless Power Consortium have created a standard called Qi (pronounced "Chee") which uses inductive electrical power transfer over distances of up to 4 cm (2 inches). The Qi system comprises a power transmission pad and a compatible receiver in a portable device. To use the system, the mobile device is placed on top of the power transmission pad, which charges it via electromagnetic induction. But unlike the UW researcher’s technology, the Qi specification is primarily targeting the recharging of a device rather than the actual powering of it.
The applications of true long haul wireless power transmission are as broad as they are exciting as Time.com’s Matt Packham explains, “given their size and wireless self-sufficiency, imagine these sensors embedded in everything from structures to vehicles to clothing. An office in a skyscraper might alert someone that a window’s been left open; a vehicle might alert you if the child lock’s been tripped or that there’s change under the seat; running shoes could let you know when you’ve reached their optimal mileage threshold. Or consider UW’s examples: bridges capable of alerting someone if stress-related cracks form, couches that sing out after they “eat” your keys and the option to send text messages or emails with “wearable” technology, battery-free.”
Reuven Cohen (rUv) is the Chief Cloud Advocate at Citrix (NASDAQ: CTXS)
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I’ve included a video below.
