Would it be possible, with a key box measuring about 12 inches deep, to set it up so that when a key was pulled (containing an RFID tag), a reader would register which key it was? Or would there be too much interference with so many tags in a small, concentrated area?
It is definitely possible. In a video I recorded at the NXP Semiconductors lab in Austria, back in 2009, 96 RFID tags were read on small vials of drugs within a confined space (see Capturing Serialized Data on 96 Drug Vials). During that same visit, NXP showed me more than 100 high-frequency (HF) tags in random orientation being read within a box. (I was asked not to film that, however, since it was part of a project for a specific customer.) I don’t think you will be able to use just any tag and reader, but if you contact NXP and reference this article, I’m sure they can help you locate a solution.
—Mark Roberti, Founder and Editor, RFID Journal
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