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Magnetic fields / RFID

  1. Apr 4, 2005 #1

    First, I´m new in this forum so I´m not sure if I´m posting in the right place. If I don´t.....well, sorry.

    Then my question...I´ll try to explain.

    I´m playing with an inductively coupled RFID-reader and smart labels.
    Holding the smart label 90 degrees with respect to the antenna, the smart label will not be detected.
    However, if I "roll" the smart-label (sort of giving it the shape of a cigarette) it is detected even though I hold it 90 degrees with respect to the antenna.

    Why does this happen?
    Are additional magnetic fields created when a smart - tag is "rolled"

    I hope my question was clear...hard to explain without pictures.

    thanks in advance

  2. jcsd
  3. Apr 5, 2005 #2
    When it is perpendicular you are not coupling enough energy to the loop antenna
    to activate the system. When you roll it, its much like tilting it and you can couple
    to the tilted or rolled antenna.
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