Abstract: A passive tag including a volatile memory is provided. The passive tag includes: a sensing unit which senses or measures information about environmental surroundings of the tag; a volatile memory; a non-volatile memory; and a control unit which firstly stores resultant data sensed or measured by the sensing unit in the volatile memory and then moves the data stored in the volatile memory to the non-volatile memory according to pre-set conditions. Therefore, the life of the tag is prolonged and stability of important data can be secured.

Abstract: According to the present invention, the apparatus receives a radio frequency (RF) signal transmitted from the Radio Frequency Identification (RFID) reader, measures the strength of the received RF signal, and controls the power supplied from the power supply unit included in the tag or the power excited by the RF signal to be supplied to the tag according to whether the power excited by the received RF signal exceeds a level necessary to operate the tag based on the measured strength of the RF signal. Thus, efficiency of power consumption of the tag and the RFID transmission/reception system can be maximized and the amount of data is reduced to the extent that the set of commands is not needed, thereby simplifying a data process.