Radio frequency identification (RFID) tags are used in a wide range of applications such as: Radio frequency animals, tracking goods through the supply chain, tracking assets such as gas bottles and controlling access into buildings.

RFID tags include a chip that typically stores a static number (an ID) and an antenna that enables the chip to transmit the stored number to a reader. Some RFID tags contain read/write memory to store dynamic data. When the tag comes within range of the appropriate RF reader, the tag is powered by the reader’s RF field and transmits its ID to the reader.