How Does RFID
Work
How Does RFID
Work: RFID System consists of three main parts; a data carrier (also
called a Tag or a
Transponder), an Antenna and a Reader unit. The Antenna generates an
electromagnetic field that energizes a chip (IC-circuit) inside the
Tag. The electromagnetic field is modulated by the Tag and the
modulated signal is recovered by the Antenna and sent to the Reader
unit for interpretation. Read and write Tags have a unique number
and a programmable memory. The reading distance is depending on the
type, size and shape of the Tag, the size and shape of the reading
and the frequency.
How Does RFID
Work? Or Working of RFID! The basic RFID system consists of three
components:
- An antenna or
coil
- A transceiver
with decoder
- A transponder
(often called a tag) that is electronically programmed with unique
information
Let’s see
closely How Does RFID Work, often the antenna is packaged with the
transceiver and decoder to become a reader (or interrogator), which
can be configured either as a handheld or a fixed-mount device.
The antenna
emits a low powered signal that generates a response from the
circuitry within the tag.
The resulting radio or microwave transmission or
electromagnetic induction (depending on the type of tag) is received
and interpreted by the transceiver. Antennas are available in a
variety of shapes and sizes, which means that they can be built into
a doorframe or indeed any object to receive tag data from passing
persons or articles.
The electromagnetic field produced by an antenna can be
constantly present when multiple tags are expected continually. If
constant interrogation is not required, a sensor device can activate
the field.
RFID tags are
categorized as either active or passive. An active tag is powered by
an internal battery, which generally gives it a longer read range
than passive tags, which obtain operating power from the reader.
Active tags are also usually read/write in comparison with typically
read-only passive tags.
While active
tags can operate with up to 1MB of memory compared to the 32 - 128
bits of passive tags, the former are larger, heavier and more
expensive than passive tags, which offer a virtually unlimited
operating existence in contrast with a maximum active tag lifetime
of 10 years. In
addition to the lesser memory size, passive tags also have shorter
reading ranges and require readers with higher power than those used
with active tags.
How Does RFID
Work, RFID systems are also distinguished by their frequency ranges.
Low-frequency (30 KHz to 500 KHz) systems have short reading ranges
and lower system costs. They are most commonly used in security
access, asset tracking, and animal identification applications.
High-frequency (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) systems,
offering long read ranges (greater than 90 feet) and high reading
speeds, are used for such applications as railroad car tracking and
automated toll collection. However, the higher performance of
high-frequency RFID systems incurs higher system
costs.
How Does RFID
Work: An RFID tag is typically tucked inside a sticker, anywhere
from two to four square inches in size. A silicon chip in the center
of the tag contains a unique identifier, a string of numbers that
identifies the contents of the carton or pallet. An RFID reader
sends a signal to the tag, asking for that information and the tag's
antenna—which is woven into the tag itself and attached to the
chip—beams it back. (Most tags have one antenna, but Matrics makes a
two-antenna tag.)
The signals
need not be read directly by a scanner, as barcodes are. Instead,
masses of RFID tags can be read in seconds, greatly cutting the time
needed to inventory packages. Developers are also working on what
are called smart tags. They will come equipped with sensors able to
detect environmental conditions—temperature or humidity, for
instance—as a package moves up and down the supply chain. Such tags
could contain a detailed account of a package's
history.
