A radio frequency identification (RFID) tag to be attached to an object to
identify the object or a characteristic or feature thereof from data
stored in the tag accessible by an RFID reader includes an
application-specific integrated circuit (ASIC), configured to process
signals from the RFID reader and return signals related to the stored
data, an interdigit AC coupling circuit, in communication with the ASIC,
a matching circuit, in communication with the interdigit AC coupling
circuit and an antenna, in communication with the matching circuit,
configured to receive signals from the RFID reader and transmit the
signals related to the stored data. The interdigit AC coupling circuit
and the matching circuit provide an AC coupling and a matching impedance
between the ASIC and the antenna respectively.