md80fanatic:
If you can read the label on a golf ball from space, in any weather, you can hear a microwatt burst from an RFID chip. Do you think the GPS system was put in place so you could have a cool moving map in your auto?
RFID do not emit anything when they are not being scanned so it is impossible to monitor the movement of a card via satellite. Not sure where you got that from but you best check your sources.
By passing an RFID chip over a card reader you are also passing it over a small induction loop that temporarily gives the small charge required for the transmission of the information. There are no batteries involved so there is no capability for continuous or intermittent transmission as speculated.