Technical jargon develops around any new
technology, and RFID is no exception. Some of these terms are quite useful,
serving as a convenient way to communicate concepts needed to describe other
concepts that will appear in the pages that follow. These terms include:
Singulation
This term describes a procedure for
reducing a group of things to a stream of things that can be handled one at a
time. For example, a subway turnstile is a device for singulating a group of
people into a stream of individuals so that the system may count them or ask
them for access tokens.
This same singulation is necessary when
communicating with RFID tags, because if there is no mechanism to enable the
tags to reply separately, many tags will respond to a reader at once and may
disrupt communications.
Singulation also implies that the reader
learns the individual IDs of each tag, thus enabling inventories. Inventories
of groups of tags are just singulation that is repeated until no unknown tags
respond.
Anti-collision
This term describes the set of procedures
that prevent tags from interrupting each other and talking out of turn. Whereas
singulation is about identifying individual tags, anti-collision is about both
regulating the timing of responses and finding ways of randomizing those
responses so that a reader can understand each tag amidst the plethora of
responses.
Identity
An
identity is a name, number, or address that uniquely refers to a thing or
place. "Malaclypse the Elder" is an identity referring to a
particular person. "221b Baker Street London NW1 6XE, Great Britain"
is an identity referring to a particular place, just as "urn:epc:id:sgtin:00012345.054322.4208"
is an identity referring to a particular widget
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