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What is RFID?
RFID stands for
Radio-Frequency
IDentification.
The acronym refers
to small electronic
devices that consist
of a small chip and
an antenna. The chip
typically is capable
of carrying 2,000
bytes of data or
less.
The RFID device (or
tag) serves a
similar purpose as a
bar code or a
magnetic strip on
the back of a credit
card or ATM card. It
provides a unique
identifier for that
object. Just as a
bar code or magnetic
strip must be
scanned to get the
information, the
RFID device must be
scanned to retrieve
the identifying
information.
There are two types
of RFID tag - active
and passive. An
active tag requires
a power source (e.g.
small battery) to
power it and
permanently
'transmit' the
unique identifier.
A passive tag on the
other hand does not
have a power source
and relies on the
detector being
placed next to the
tag for it to take
power from the
detector to generate
the code.
There
is a significant
cost difference
between active tags
(which can cost up
to a few pounds per
tag) and passive
tags which can cost
fractions of pence
per tag. Tags can
come in a wide
variety of materials
all shapes and
sizes. From printed
labels to key fobs
and screw in devices
for out door use
through to even skin
implants (e.g.
tagging of animals).
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