Go Down

Topic: How do RFID tags work? (Read 529 times) previous topic - next topic

123Splat

Feb 25, 2013, 09:23 pm Last Edit: Feb 25, 2013, 09:44 pm by 123Splat Reason: 1
In the Project Guidance tab there is a wonderful thread (AWOL locked it just when it was getting fun), by some fellow who wanted to use an Arduino to generate jamming signals around 100MHz.  It is a real fun read.  

Anyway, in a discussion of various things that the FCC could and couldn't regulate, this guy brings up RFID tags.  The response by a knowledgable member was that RFID tags operated in an unrestricted Freq. band.

My understanding is that the FCC pretty much only cares about emmisions, and I thought that RFID tags did not emit anything, they just caused resonance or disturbance in a detecting field (something like beat freq in a metal detector). I know I'm old and feable,but Did I miss something in how the tagd work?

AWOL

Please tone down the personal attacks.
Glass houses, and all that.
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.

Grumpy_Mike

Some RFID tags take in power at one frequency and use it to power a transmitter at another. This is how the 13MHz tokens work. Most of the 125KHz tokens work with inductive coupling like you thought.

123Splat

AWOL:  Sorry, I believe I have corrected the offending language.

Grumpy:  Thanks.  Just goes to show how far in the past I live.  Time to do more research......

Go Up
 


Please enter a valid email to subscribe

Confirm your email address

We need to confirm your email address.
To complete the subscription, please click the link in the email we just sent you.

Thank you for subscribing!

Arduino
via Egeo 16
Torino, 10131
Italy