Could the phone then automatically relay that information during an emergency call to 911?
Cellular systems operate at 800 MHz and higher frequencies, so an active RFID system operating at 433 MHz could not communicate directly with a cell tower. It would be like trying to listen to an FM station with an AM-only radio. Plus, RFID systems have their own communications protocol, which differ from cellular network protocols.
You could, of course, hook up a cellular phone to a reader, then write software that would trigger a call to 911 and relay data (for instance, "Tag 123456789 was read at 8:01 AM"). I'm not sure what they would do with that information, but it should be possible.
I hope this answers your question, and I look forward to seeing you next month at RFID Journal LIVE! 2017.
—Mark Roberti, Founder and Editor, RFID Journal
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