RFID How It
Works
RFID How It
Works: 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.
RFID How It
Works? 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 RFID How It Works, 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.
RFID How It
Works, 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.
RFID How It
Works: 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.
