Rfid tags are affixed to items in order to track them using an rfid reader and antenna.
Rfid tag magnetic field.
Sketch of magnetic ux around an axial conflguration square loop reader operating near a perfect conducting metal surface with an rfid tag on a magnetic rf isolator pad.
Originally rfid tags were used to track large items like cows railroad cars and airline luggage that were shipped over long distances.
These original tags called inductively coupled rfid tags were complex systems of metal coils antennae and glass.
The little bit of research i ve done hasn t been able to uncover any issues of interference to rfid by magnetic fields except for one paper which studied the effects of magnets in the digestive track of cattle on rfid ear tags and found that some interference did occur in some cases.
Magnetic field cross section square readerantenna inductive.
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Its all about speed of the movement of the rfid tag relative to the magnetic field.
A static magnetic field caused by a normal magnet should not cause any harm to a rfid tag.
Inductively coupled rfid tags were powered by a magnetic field generated by the rfid reader.
Intelligent rfid tag for magnetic field mapping download pdf info publication number us7772978b1.