In an
RFID system the
transponder which contains the data to be transmitted is
called an
RF tag. Passive RF tags obtain operating power
generated from the RF reader. They are smaller and lighter than active tags
but have a shorter communication range and require a high powered reader. Passive tags
are generally read-only and as such, once it is programmed with data, that
data cannot be modified.
The opposite of a passive tag is an active tag.