Where can I learn more about this?
Yes, there are. In general, passive low-frequency (LF) tags work best in the presence of metal. Companies such as RFID, Inc. offer LF tags that can be embedded into a small hole drilled into a metal pipe or bar. Passive high-frequency (HF) tags can also work in metal. InfoChip manufactures tags that are designed to be inserted into a metal hole drilled into oil pipes and other metal objects that need to be tracked.
Passive ultrahigh-frequency (UHF) tags have the most problems around metal, due to the way the tags communicate with readers. But even here, we have seen smart engineers find ways to get around such issues. Several companies have introduced passive UHF tags that can be embedded in metal. Omni-ID‘s FIT 200 tag, for example, is a small, passive UHF tag that can be attached to or embedded in metal.
If you are Premium Member, I recommend you read “A Guide to Embeddable RFID Metal Tags.”
—Mark Roberti, Founder and Editor, RFID Journal
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