Radio-frequency identification (RFID) refers to any technology that uses radio waves to instantly recognise people or objects. In order to work properly, RFID systems require two components, both of which have antennas:

  • A tag (or transponder) equipped with a microchip
  • A reader (also known as an interrogator)

Many organisations use RFID technology in ID cards. For example, suppose an employee with an RFID tag wants to enter a room. Near the door lock is a reader, which is programmed to grant access to authorised personnel. When the worker places his or her tag near the interrogator, the door may either open or remain closed, depending on the individual’s security clearance.

The technology behind it 

A reader uses a power source, whether it be batteries or connected electricity, to send out radio-frequency signals over a short distance. When these signals come into contact with a transponder, the tag receives the energy it needs to operate and sends its information to the interrogator.

The reader then uses a decoder to interpret the information from the tag. Revisiting the example from above, let’s assume the door lock’s interrogator is connected to the internet. The reader communicates with a cloud-hosted database, which describes people who are approved to enter the secured room. If the employee’s name and ID code is listed in the database, the door will open.

Not every RFID system is the same

Bear in mind that this is just one way RFID technology operates. For instance, the reader may not have to communicate with a database over the web to grant entry. In addition, there are RFID tags that are active, meaning they use their own power sources to proactively transmit data.

While active RFID tags can distribute signals over a wide range, they do have limited life spans and require batteries. Passive RFID transponders are generally cheaper, and can be used over an unlimited amount of time.

For most organisations, printing ID cards with RFID capabilities is a solid option. The technology allows quick and easy access to facilities and enables administrators to exercise greater security controls.