This reminds me of how RFID passports are 24/7 broadcasting the nationality of their holder. Back in the mid-2000s, I remember a proof-of-concept which only detonated a bomb if a USA passport passed within 20ft of it.

Scary stuff. I sure wouldn't want to be walking around with a high-targetable beacon[†] #ACAB

†: in before "but ur phone blahblahblah" (don't own one)