Researchers may have detected signals from the universe’s first stars

The early development of our universe is still quite a mystery, but in a new study published today in Nature, researchers describe what may be evidence of when the first stars began to form. After the Big Bang, which took place some 13.7 billion year...

Astronomers just measured a whole lot more than gravitational waves

A couple of weeks ago, the LIGO (Laser Interferometer Gravitational-Wave Observatory) and Virgo teams announced the detection of another set of gravitational waves -- the fourth since LIGO's first detection in September of 2015. The observations of t...

Your future devices might not need wireless radios

Seemingly every connected device has at least one wireless radio in it. However, that often requires some big compromises. Those radios often chew up a lot of power, which isn't always practical with Internet of Things gadgets that may not have muc...

Wireless charging tech harvests your phone’s wasted radio waves

When you think of wireless charging, you probably think of special charging pads for your phone. But what if your phone could partly charge itself? Radient Micro-Tech claims to have managed just that. It just received two patents for technology that...

University of Washington harnesses RF and TV waves for battery-free wireless devices (video)

The problem with power is that, eventually, it runs out. To help cope with this inevitability, scientists at the University of Washington have developed prototype "ambient backscatter" devices that can passively harness the juice in radio and TV waves. Because they don't generate their own signal, these devices can get by on the juice they siphon from the air -- communicating by absorbing or reflecting binary information from existing signals, instead. According to the researchers, these signals can travel as far as 6.5 miles from a TV tower at speeds of 1KB per second.

Although the project is still in its infancy, its creators are already thinking up practical applications. Ambient backscatter tags could be built into buildings or bridges, for instance, and alert monitoring stations to potential structural damage or defects. The team also imagined tagged keys and furniture, warning a user if they accidentally dropped something between the couch cushions -- all without an energy source. This type of tech could bring us closer to the internet-of-things future we've been promised, allowing smart communications to exist virtually anywhere. The Huskies said this could even enable a dead smartphone to send TV signal-powered text messages -- which could be great considering how often we forget to charge our handsets.

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Via: Dvice

Source: University of Washington

Stanford researchers make heart implant powered by radio waves, put batteries out of a job

Stanford researchers make heart implant powered by radio waves, put batteries out of a job

Batteries used to be the only way to power implantable gadgets, but additional surgeries are needed to replace the power packs once their juice runs out -- a less-than-ideal solution for patients. Recent discoveries, however, have such medgadgets being powered by photons, hip hop and now high-frequency radio waves. Electrical engineers at Stanford built a cardiac device that uses a combination of inductive and radiative transmission of power, at about 1.7 billion cycles per second, to its coiled receiving antenna.

Previous prevailing opinion held that the high frequencies needed for wireless power delivery couldn't penetrate the human body deep enough, and the lower frequencies that would do the trick require antennas too large to work as implants. That conundrum was solved by getting the high-frequency signals to penetrate deeper using alternating waves of electric and magnetic fields. That allowed a 10x increase in power delivery -- up to 50 microwatts to a millimeter radius antenna coil -- to an implant five centimeters below the skin. That antenna also was also designed to pull power regardless of its orientation, making it ideal for applications inside always-moving human bodies. Of course, the implant's really just a proof-of-concept at this stage, but hopefully it won't be long before battery powered implants go the way of the dodo TouchPad.

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Stanford researchers make heart implant powered by radio waves, put batteries out of a job originally appeared on Engadget on Sun, 02 Sep 2012 23:56:00 EDT. Please see our terms for use of feeds.

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Researchers use ambient WiFi radio waves to see through walls

Researchers use ambient WiFi radio waves to see through walls

Seeing through walls hasn't been a super hero-exclusive activity for a while now. According to Popular Science, however, University College London researchers Karl Woodbridge and Kevin Chetty have created the first device that can detect movement through walls using existing WiFi signals. While similar tech has required a bevy of wireless nodes, the duo has pulled off the feat with a contraption roughly the size of a suit case.

Much like radar, the device relies on the Doppler effect -- radio waves changing frequencies as they reflect off of moving objects -- to identify motion. Using a radio receiver with two antennas and a signal-processing unit, the system monitors the baseline WiFi frequency in an area for changes that would indicate movement. In tests, the gadget was able to determine a person's location, speed and direction through a foot-thick brick wall. The technology's potential applications range from domestic uses to scanning buildings during combat. Best of all, since the university's hardware doesn't emit any radio waves, it can't be detected. How's that for stealthy?

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Researchers use ambient WiFi radio waves to see through walls originally appeared on Engadget on Fri, 03 Aug 2012 08:24:00 EDT. Please see our terms for use of feeds.

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