Also, how can we ensure that an RFID system will work as expected?
If you have 1,000 RFID tags, you can set up a database listing the unique serial number of every tag. You can then send a command to the reader, instructing it to interrogate all tags within the read field. The serial number of each tag read can be checked against the IDs in the database. If the device only reads 999 tags, then there will be one tag in the database that is not confirmed as read.
This is a very common application with passive UHF RFID readers. Typically, a company will have an inventory list with a unique tag ID associated with each item in inventory. It will then take inventory with the RFID system and use software to generate a report that says which tags were not read, and list any tags that were interrogated that were not on the original list. An item might have been returned to inventory, for example, and the inventory system might not have been updated.
If a tag was not read, it could mean the item was stolen from inventory, or that it is there but the tag was not read for some reason. You would need to manually investigate why a specific tag was not read.
—Mark Roberti, Founder and Editor, RFID Journal
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