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Visualizing RFID
jamie found a video on Warren Ellis's blog introducing a new way to visualize RFID fields. The film is by Timo Arnall and Jack Schulze. The subject is introduced in words on the BERG site (a design consultancy); the tech behind it is explored at Touch, a project that experiments with near-field communications. "This image is a photographic mapping of the readable volume of a radio field from an RFID reader. The black component in the image is an RFID reader... The camera has been fixed in its position and the reader photographed. Using a tag connected to an LED we paint in the edges of the readable volume with a long exposure and animate them to show the form."
Remember, anything radio is not theoretically limited in range. Only practical implementations have set limits.
Whilst I never thought of doing this with RF fields, it's not exactly amazing. It is, however, very interesting!
Using their technique, we can now profile our cards to provide maximum protection with minimum tinfoil!
We've already been tagged with cellular and our credit line. Anything else is just marketing research and behavioral analysis.
Here is the link to the non-embedded video.
http://vimeo.com/7022707
"It's because they're stupid, that's why. That's why everybody does everything." -Homer Simpson
You could do this in Matlab pretty easy.
It's a practical, reproducible way of visualizing E and B fields, just like you learned in high school and college electromagnetics. Cool stuff.
Didn't you see "Minority Report?"
1. Pick up RFID chip
2. Look at it. It's an RFID chip! You have just visualized it.
3. ???
4. Profit
These posts express my own personal views, not those of my employer
Are these guys geeks or in the media field? That's an incredibly well shot video if its just geeks producing it.
And as for some haters calling this lame- I think its very interesting to have a visual idea of how an everyday product works. At least we know swiping our RFID cards flat will make for easier reading.
The free field pattern near a loop antenna is nothing new. RFID or any other application such as a transmitter for the heairng impaired makes no difference.
A 3D plot of a simple loop antenna can be seen on this page;
http://vk1od.net/antenna/SmallUntunedSquareLoop/
The 3D plot is near the bottom of the page.
It it resembles the magnetic field of a bar magnet or a coil of wire with a current, that is no supprise.
The truth shall set you free!
Yes, but e.g. ISO 14443 RFID passive responses (e.g. the ones used in ICAO-specified RFID passports and paypass cards) very quickly go below ambient background noise, in effect limiting even the theoretical range to 1-2 m for all but most exotic radio-noise free environments.
Passive RFID is only half-radio, really. ;-)
The subtlety seems to be that they're not plotting an RF field, they're plotting the volume in which the passive tag will respond to an RF field (of a given strength). It's another level of abstraction. Yes, once somebody has come up with the idea then the implementation looks simple enough, but the idea is quite remarkable.
Quidnam Latine loqui modo coepi?
Except the E and B fields being visualised are not there. The tag is passive, it does not broadcast. You've missed the point of what they're doing.
Quidnam Latine loqui modo coepi?
but neither does sound, light, your body(ok so using QM is cheating) but background noise quickly makes practical limits, hard limits (you can edge around the limit but if the signal is noisey and the noise is noisey there is not much you can do)
IranAir Flight 655 never forget!
There are 2 meanings of passive. An HF tag being read is coupled to the field reading it. It is actively modulating the field, but it's not radiating. It's not a radio at all. It's passive in that sense, but not really, regardless of what terms are used in the specs.
Passive snooping is reading the field modulation by a device that is not powered by the field itself, and this can be done at greater distances by sophisticated receivers.
...is that now we can devise a device that warns us when we approach an RFID reader so we can avoid it!
The RIFD probe!
Oh look honey, my probe is blinking, we'd better go back the way we came.
Is this device a radio wave camera? I've been looking for a way to get a 2-D image of radio waves. Am I correct in thinking that the wave output from an antenna is a 1-dimensional output ( two if you count time ) ? I'd like to try to get pictures of wave interference
Computers are useless. They can only give you answers.
-- Pablo Picasso