Radio-frequency identification

Radio-frequency identification (RFID) uses <a href="/facts/Electromagnetic_field/MacraS8y">electromagnetic fields</a> to automatically <a href="/facts/Automatic_identification_system/9yyPSH9p">identify</a> and <a href="/facts/Tracking_system/4fKPC7Fp">track</a> tags attached to objects. An RFID system consists of a tiny radio <a href="/facts/Transponder/cmqcWPwE">transponder</a> called a tag, a <a href="/facts/Radio_receiver/5olDTxkg">radio receiver</a>, and a <a href="/facts/Transmitter/nFYghtKv">transmitter</a>. When triggered by an electromagnetic interrogation pulse from a nearby RFID reader device, the tag transmits digital data, usually an <a href="/facts/Identifier/pPaQPLhj">identifying inventory number</a>, back to the reader. This number can be used to track <a href="/facts/Inventory/vSBu0d9r">inventory</a> goods.
Passive tags are powered by energy from the RFID reader's interrogating <a href="/facts/Radio_wave/XmB6WPpF">radio waves</a>. Active tags are powered by a battery and thus can be read at a greater range from the RFID reader, up to hundreds of meters.
Unlike a <a href="/facts/Barcode/Mkh4cCTp">barcode</a>, the tag does not need to be within the <a href="/facts/Line-of-sight_propagation/w4xfQd2o">line of sight</a> of the reader, so it may be embedded in the tracked object. RFID is one method of <a href="/facts/Automatic_identification_and_data_capture/voSLBXpx">automatic identification and data capture</a> (AIDC).
RFID tags are used in many industries. For example, an RFID tag attached to an automobile during production can be used to track its progress through the <a href="/facts/Assembly_line/uENUURd9">assembly line</a>, RFID-tagged pharmaceuticals can be tracked through warehouses, and <a href="/facts/Microchip_implant_(animal)/t1mpJxWF">implanting RFID microchips</a> in livestock and pets enables positive identification of animals. Tags can also be used in shops to expedite checkout, and to <a href="/facts/Anti-theft_system/Ude3S3lE">prevent theft</a> by customers and employees.
Since RFID tags can be attached to physical money, clothing, and possessions, or implanted in animals and people, the possibility of reading personally-linked information without <a href="/facts/Consent/49VpqNsH">consent</a> has raised serious <a href="/facts/Right_to_privacy/q9jY2KWz">privacy</a> concerns. These concerns resulted in standard specifications development addressing privacy and security issues.
In 2014, the world RFID market was worth US$8.89 <a href="/facts/Billion/d9KjEYSt">billion</a>, up from US$7.77 billion in 2013 and US$6.96 billion in 2012. This figure includes tags, readers, and software/services for RFID cards, labels, fobs, and all other form factors. The market value is expected to rise from US$12.08 billion in 2020 to US$16.23 billion by 2029.

Radio-frequency identification open-in-new

Radio-frequency identification