Could RFID help me find the animals?
If you are asking whether you can determine a cow’s precise location in real time via an ear tag, the answer is no. Such tags generally have a read range of about 3 feet, though some use ultrahigh-frequency (UHF) tags with a range of 20 to 39 feet. Passive tags can only be interrogated when they are within the field of a passive RFID reader.
The way these systems work is that you would place readers at entry and egress points. As an animal passed a reader to enter the barn or field, its tag would be read and the location would be updated in a database. Readers could also be installed at milking stations to determine which cows provided milk.
—Mark Roberti, Founder and Editor, RFID Journal
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