 |
See Through Walls With Wireless Networks
See through walls by using the way signal strength varies in wireless networks? It ought to be possible and now researchers at the University of Utah say that they can do it with variance-based radio tomographic imaging (VRTI).
According to their paper, VRTI images movement, not static changes in attenuation. In the image below, a human subject is taking small steps randomly around and through the space marked as (17.6, 21.3) in the graph shown below. The white spot shows where VRTI 'sees' the subject.
(Wireless network spying with variance-based radio tomographic imaging )
The basic idea is straightforward. The signal strength at any point in a network is the sum of all the paths the radio waves can take to get to the receiver. Any change in the volume of space through which the signals pass, for example caused by the movement of a person, makes the signal strength vary. So by "interrogating" this volume of space with many signals, picked up by multiple receivers, it is possible to build up a picture of the movement within it.In tests with a 34-node network set up outside a standard living room, Wilson and Patwari say they were able to locate moving objects in the room to within a meter or so.
Interested in seeing through walls? Take a look at four different technologies - Prism 200, LEXID handheld, LifeReader and the DARPA Radar Scope.
Science fiction fans have enjoyed various versions of this technology for many years. Consider the Subphoton Search Ray from The Shining One (1937), the Probability Time Wave Tube from Elimination (1936) and the X-Beam Projector from Diamond Planetoid (1937).
From Through-Wall Motion Tracking Using Variance-Based Radio Tomography Networks via MIT's Technology Review.
Scroll down for more stories in the same category. (Story submitted 10/1/2009)
Follow this kind of news @Technovelgy.| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
Would
you like to contribute a story tip?
It's easy:
Get the URL of the story, and the related sf author, and add
it here.
Comment/Join discussion (Back On) ( 0 )
Related News Stories - (" Surveillance ")
Smartphone Sensor System Tracks Gunfire
'Sound trackers on the roof could zero in on weapons action...'-Greg Bear, 2007.
SHEPHERD-MIL, A Birdlike Soaring UAV
'When he had first built them, they had been crude indeed, flying mechanisms with little more than a reflex-response unit.'- Philip E. High, 1968.
AXON Flex And Stross' Cop Specs
'Arriving on SOC... Start evidence log." [E]verything you see on duty goes into the black box.'- Charles Stross, 2007.
India Opts For Nationwide Iris Scanning
'The road you're on, John Anderton, is the one less traveled...'- Steven Spielberg, 2002.
Technovelgy (that's tech-novel-gee!) is devoted to the creative science inventions and ideas of sf authors. Look for the Invention Category that interests you, the Glossary, the Invention Timeline, or see what's New.
Current News
German Firm Seeks To Recruit Autistics
Not a deficit, but a strength.
NASA Supports Pizza Printer
Is it extra with printed pepperoni?
Could Ground-Based Lasers De-Orbit Space Junk?
'Then their lasers vaporized the smaller satellites...'
'Hello, Computer!' Google Now Highlighted at IO13
'Hello, computer!'
MIT Robot Cheetah Video Shows Gait Transition
'The legs are long, curled way up to deliver power, like a cheetah's.'
TrackingPoint Smart Rifle
Not your typical 'smart bullet' approach.
Sky City's 220 Stories Are Go
'It rested among green parklands and... stood in total isolation, a glittering block of whites and flashing windows dotted with colors.'
CARMAT Bioprosthetic Total Human Heart Replacement
'George Walt's corporate existence proved the workability of wholly mechanical organs...'
Personal Sniffer Robots
'...The ticking combinations of the olfactory system of the hound.'
Physical Exam? We've Got Apps
See the future of handheld, personal medical devices.
The Interplanetary Internet, Vint Cerf Speaking
'This was the center of Interplanetary Communications.'
Drosophila Robotica, The Mechanical Fly
'... the Scarab [flying robot] buzzed into the great workroom as any intruding insect might...'
Robo-Raven Flapping Wing Robot Bird
'When he had first built them, they had been crude indeed, flying mechanisms with little more than a reflex-response unit.'
Japan's Nursing Home Robot Plan
Let's make the Roujin Z-0001 Robotic Bed!
Samsung Smart TVs With Gesture Control
'He waved his hand and the circuit switched abruptly.'
Swiss HCPVT Giant Photovoltaic 'Flower'
'...leaning against one of the slender stalks of a sunshade-photocell collector.'
