The Basics of RFID Technology

RFID is a radio frequency identification tool and is a computing technology where the use of an object: the RFID tag is attached to an item for tracking or identification purposes.  The tags are read through the use of radio waves.  Most RFID tags contain two parts: “an integrated circuit for storing and processing information, detecting the radio frequency signal, and some other specialized functions; and an antenna for receiving and transmitting the signal (Wikipedia).”  The majority of RFID tags have a silicon microchip that stores a unique number and some additional information about the item it is attached to (RFID Journal).

There are two main categories of RFID tags: passive and active.  Passive tags do not contain a transmitter while active tags have their own transmitter.  Passive tags reflect back energy from the reader antenna while active tags produce their own energy.  Some active tags have battery power (RFID Journal).

Active tags are used more for keeping track of cargo, rail cars, and reusable containers that are tracked over long distances.  They generally have a read range of 60-300 feet.  Some other uses of active tags are at toll booths for payment collection or checkpoint control.  When they are used this way both a transponder and a beacon are needed; the beacon sends a signal to the transponder as it approaches and then the tag with the transponder broadcasts it unique ID back to the beacon’s reader.  These operate on a radio signal of about 455 MHz, 2.45 Ghz or 5.8Ghz (RFID Journal).

Passive RFID tags are cheaper than active tags and require no maintenance, which is why they are use more often by retailers and manufacturers to attach to their products.  They have a short read range of about a few inches to 30 feet.  This type of tag is also useful in libraries for them to attach to their materials.  In a passive RFID tag the transponder is made of a microchip which is attached to an antenna.  It can be mounted on a substrate or stuck between and a layer of adhesive and a paper label or a smart label.  They can also be embedded in plastic cards, key holders, and the walls of packaging.  They operate at a low frequency, high frequency or ultra-high frequency radio signal (RFID Journal).

What is RFID?

RFID is an auto-ID technology that can include bar codes, optical character readers and even retinal scans.  They are used to improve accuracy and save time and money in labor costs where previously information was entered manually (RFID Journal).

How RFID Works

RFID tags are used to store data and can be updated or changed as needed.  The technology offers a better way to track merchandise.

The basic process for how RFID works is:

• “Data store on a tag’s microchip waits to be read
• The tag’s antenna receives the energy from the RFID reader’s antenna
• Using power from its internal battery or power harvested from the reader’s electromagnetic field, the tag sends radio waves back to the reader
• The reader picks up the tag’s radio waves and interprets the frequencies as meaningful data” (How Stuff Works -- RFID Journal)

Libraries

RFID technology is also being used in libraries.  The technology has begun to slowly replace the traditional barcodes used on library items (books, CDs, DVDs, etc).  The information on the tag is read by an RFID reader, which has replaced the barcode reader commonly found at a library’s circulation desk.  The technology has enhanced the workflow in the library setting (Wikipedia).