Updated July 4,
Radio frequency identification (RFID) uses radio transmitters to
read data stored in tag-based transponders
at distances. RFID technology is used to track assets, manage inventory
and authorize payments. Walmart is one of the biggest adopters of
the technology. So far that's the first thing the world can thank
RFID tags contain a silicon chip,
for data storage, and a miniature antenna that receives and sends
signals to an RFID reader. The tag and antenna are typically printed
or etched on an electronic substrate, which is then embedded in
a plastic or laminated paper tag.
RFID tags can be passive or active.
Passive is the most popular, because this is the cheapest tag. In
the passive case the antenna harvests some of the energy that the
RF scanner shines on it, converting it to direct current by means
of a detector circuit. Passive tags can only be read from about
20 feet, because of the limitation placed on the scanner output
power. These tags cost about $0.25 now, and some day they will cost
less than $0.01. At this point there will be no limitation on what
is tagged with RFID!
Active RFID allows user-programmable
data storage. The Exxon Mobile SpeedPass is an example of an active
Hey RFID suppliers - make this
your page for short money! Contact
us for details.