RFID TECHNOLOGY ( part 1 - origin )

WHAT IS RFID?

                Radio frequency identification, or RFID, is a generic term for technologies that use radio waves to automatically identify people or objects. There are several methods of identification, but the most common is to store a serial number that identifies a person or object, and perhaps other information, on a microchip that is attached to an antenna (the chip and the antenna together are called an RFID transponder or an RFID tag). The antenna enables the chip to transmit the identification information to a reader. The reader converts the radio waves reflected back from the RFID tag into digital information that can then be passed on to computers that can make use of it.

RFID TAGS

There are two types of RFID tags.

Passive tags - RFID tags are thinner than a sheet of paper. Passive RFID tags use the electrical current induced in the antenna by the incoming radio frequency scan. This means that the response of a passive RFID tag is brief.

Active tags - Active RFID tags have their own power source that enables longer range frequency as well as larger memory capacity. This allows it to store additional information. Active RFID tags are used to track high-value goods that need scanning over long ranges.

History of RFID Technology

Radio frequency identification has been around for decades. Learn how it evolved from its roots in World War II radar systems to today's hottest supply chain technology.

It’s generally said that the roots of radio frequency identification technology can be traced back to World War II. The Germans, Japanese, Americans and British were all using radar—which had been discovered in 1935 by Scottish physicist Sir Robert Alexander Watson-Watt—to warn of approaching planes while they were still miles away. The problem was there was no way to identify which planes belonged to the enemy and which were a country’s own pilots returning from a mission.

 Under Watson-Watt, who headed a secret project, the British developed the first active identify friend or foe (IFF) system. They put a transmitter on each British plane. When it received signals from radar stations on the ground, it began broadcasting a signal back that identified the aircraft as friendly. RFID works on this same basic concept. A signal is sent to a transponder, which wakes up and either reflects back a signal (passive system) or broadcasts a signal (active system).

The First RFID Patents 

Mario W. Cardullo claims to have received the first U.S. patent for an active RFID tag with rewritable memory on January 23, 1973. That same year, Charles Walton, a California entrepreneur, received a patent for a passive transponder used to unlock a door without a key. A card with an embedded transponder communicated a signal to a reader near the door. When the reader detected a valid identity number stored within the RFID tag, the reader unlocked the door. Walton licensed the technology to Schlage, a lock maker, and other companies.