Loading...
Pages: [1]   Go Down
Author Topic: How do RFID tags work?  (Read 202 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Jr. Member
**
Karma: 1
Posts: 78
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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?
« Last Edit: February 25, 2013, 03:44:22 pm by 123Splat » Logged

Global Moderator
UK
Online Online
Brattain Member
*****
Karma: 143
Posts: 19379
I don't think you connected the grounds, Dave.
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Please tone down the personal attacks.
Glass houses, and all that.
Logged

Pete, it's a fool looks for logic in the chambers of the human heart.

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 299
Posts: 26031
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

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.
Logged

Offline Offline
Jr. Member
**
Karma: 1
Posts: 78
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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......
Logged

Pages: [1]   Go Up
Print
 
Jump to: