RFID - Radio-frequency identification

RFID - Radio-frequency identification

Radio-frequency identification is a radio waves communication based technology using the exchange of data between an electronic tag attached to an object and a reader that finds many applications in different domains for identification and tracking. Léon Theremin's 1945 spy invention is considered the grandfather of RFID technology.

With the continuous improvements in technology and the existence of both passive and active RFID tags, it is time to consider their use in the field of protection, automation and control.

RFID technology represents a significant improvement in comparison with older asset tracking technologies, such as pen and paper or barcode based technologies.

Some of the deficiencies of barcode technology are the limited amount of information that can be coded – typically brand and type of the item, as well as the ability to read only a single tag.

The same way that barcode technology changed the way we track objects several decades ago, now RFID technology is changing the way we can track anything - assets, people, work in progress. One of the key improvements is the ability to store.

RFID tags can be divided in three main groups:

  • Passive  tags- without a battery
  • Active tags - with a battery that allows continuous broadcasts
  • Battery assisted passive (BAP) - has a small battery on board that is activated when in the presence of an RFID reader

Most RFID tags contain at least two parts:

  • Integrated circuit for storing and processing information, modulating and demodulating a radio-frequency (RF) signal, and other specialized functions
  • Antenna for receiving and transmitting the signal

One of the RFIDs ' improvements is that they can be read remotely and beyond the line of sight of the reader. At the same time multiple tags can be read almost simultaneously, thus improving the efficiency of the system. RFID tags also have the potential to function as low-cost remote sensors that broadcast  telemetry back to a base station. The tag's antenna receives electromagnetic energy from the reader's antenna that is used to send radio waves back to the reader, which interprets the frequencies as meaningful data.

If the reader reads tags in a stationary position, it is called fixed RFID, otherwise it is called mobile RFID. Mobile readers include hand held, carts and vehicle mounted RFID readers.