rfid Radio Frequency Identification

What is RFID ?

Radio Frequency Identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. An RFID tag is a small object that can be attached to or incorporated into a product, animal, or person. RFID tags contain silicon chips and antennas to enable them to receive and respond to radio-frequency queries from an RFID transceiver. Passive tags require no internal power source, whereas active tags require a power source.

The Beginning of RFID

In 1945 Léon Theremin invented an espionage tool for the Soviet government. Even though this device was a passive covert listening device, not an identification tag, it has been attributed the first known device and a predecessor to RFID technology. The technology used in RFID has been around since the early 1920s according to one source (although the same source states that RFID systems have been around just since the late 1960s).

A similar technology, the IFF transponder, was invented by the British in 1939 [2], and was routinely used by the allies in World War II to identify airplanes as friend or foe.

Another early work exploring RFID is the landmark 1948 paper by Harry Stockman, titled "Communication by Means of Reflected Power" (Proceedings of the IRE, pp 1196-1204, October 1948). Stockman predicted that "...considerable research and development work has to be done before the remaining basic problems in reflected-power communication are solved, and before the field of useful applications is explored." It required thirty years of advances in many different fields before RFID became a reality.

RFID systems have gained popularity, and notoriety, in recent years. A driving force behind the rapid development of RFID technology has been the rise of pervasive commerce, sometimes dubbed the quiet revolution. Pervasive commerce uses technologies such as tracking devices and smart labels embedded with transmitting sensors and intelligent readers to convey information about key areas where consumers live and work to data processing systems. To gather this data, retailers can choose from a range of options.

RFID systems may be roughly grouped into four categories:

EAS (Electronic Article Surveillance) systems: Generally used in retail stores to sense the presence or absence of an item. Products are tagged and large antenna readers are placed at each exit of the store to detect unauthorized removal of the item.

Portable Data Capture systems: Characterized by the use of portable RFID readers, which enables this system to be used in variable settings.

Networked systems: Characterized by fixed position readers which are connected directly to a centralized information management system, while transponders are positioned on people or moveable items.

Positioning systems: Used for automated location identification of tagged items or vehicles.

These RFID systems enable business owners to have real-time access to inventory information, as well as a broader, clearer picture of consumers' buying habits. RFID technology also enables retailers and corporations to peek into the lives of consumers in ways that were, until recently, off limits. Products embedded with RFID tags can continuously transmit information ranging from an electronic product code (EPC) identifier, to information about the item itself, such as consumption status or product freshness. Data processing systems read and compile this information, and can even link the product information with a specific consumer.

This composite information is vastly superior—and more invasive—than any data that could be obtained from scanning bar codes, or even loyalty cards. Frequent shopper cards link consumers to their purchases, but this limited information gives retailers only a narrow view of a consumers' in-store purchasing trends. In contrast, RFID systems enable tagged objects to speak to electronic readers over the course of a product's lifetime—from production to disposal—providing retailers with an unblinking, voyeuristic view of consumer attitudes and purchase behavior.

Related Articles: