What is the difference in time when the tag receives a message and when it replies with a response?
In general, passive UHF RFID transponders respond very quickly (within microseconds) to commands from a reader. However, some integrated circuits in transponders take slightly longer to wake up than others. To quantify the amount of time it takes a tag to respond, from the time it receives a signal from the reader, you will need to use specialized test equipment. Voyantic‘s Tagformance system, for example, is capable of measuring the response time.
—Mark Roberti, Founder and Editor, RFID Journal
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