Radio-Frequency Identification (RFID) is the process of using electromagnetic waves to identify and track electronic tags attached to specific objects. The electronic tag is comprised of a small computer chip and an antenna. Information stored on the computer chip identifies the object in question.
A typical RFID system includes a scanning antenna (to transmit the radio signal), a transponder / RFID tag (to receive the radio signal) and a transceiver-decoder (to receive and interpret the returning radio signal).
Most RFID systems are designed to be used over short distances. Radiation emitted by the radio signal powers the RFID tag attached to the object. Many RFID tags are called “passive” tags, as they don’t require a battery. Conversely, RFID tags which operate over longer distances and require a battery are called “active” tags.
A key advantage of an RFID tag over a barcode label is that “line-of-sight” isn’t required. This makes RFID tags useful for identifying and tracking people (eg. prisoners, dementia patients), animals (eg. livestock, pets) and items of financial value.