Extreme-Range RFID
Now that I’ve given the first of my Vegas talks I wanted to post everything online for anyone who couldn’t attend in person.
Slides are here (OpenOffice format)
Whitepaper is here (PDF)
ID-Me
217 feet is the range I set; I believe that’s a world record (beating both the 69 feet from Flexilis at Defcon 13 and the 65 meters claimed by ThingMagic in a Google Tech Talk). My equipment is capable of far more but I hit the limit of my range; a chainlink fence a few hundred yards away was reflecting the RF power, meaning that more power led to greater interference and hence lower range. That 217 feet used just 10W of RF power; my current amp is rated at 70W and will probably deliver a hundred watts if it’s cranked right up – it should be plenty capable of 500+ feet reads.
I’m keen to demo this in-person while in Vegas; the demos at the talk are always constrained by the room (again, reflections from the chairs, the people, and the back wall of the room) so if someone can come up with a suitable place to test I’m happy to demo multi-hundred-feet reads. I suspect that the top of a building would be ideal; reflections from the ground should be directed outward and not pose a problem (it’s also worth noting that the commercial reader I started with has a lot less problem with reflections, however it’s not legal to just amplify the signal directly for reasons I discuss in the talk).
If anyone has ideas on how to set this up please get in touch; if all else fails I’ll try to get the folks from Guinness World Records to officially certify the read range, and/or set up a demo for press back in California at a later date.
Additionally I’m going to run an RFID read range competition at Defcon next year (details to come at Defcon). I had a huge amount of fun playing with this stuff, I learned a lot, and can think of about a thousand ways to improve on my own record. Think you can do better? Do it – and bring the results to Defcon next year!
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