RFID is an technology that uses radio-frequency
waves to transfer data between a reader and a
movable item to identify.
RFID is fast, reliable, and does not require physical
sight or contact between reader/scanner and the
RFID tags are the heart of the RFID system because
they store the information that describes the object
Integrated circuit, Data is stored in ic and transmitted
to the reader
Tags are classified
3. Semi passive
Contain a battery that runs the microchip’s
Tag is able to send a stronger signal to the
reader due to battery.
Allows a read range of about one hundred feet.
Passive tags contain no batteries.
Passive tags get power from a reader.
Readers send electromagnetic waves that
produce a current in the tag’s antenna which
then powers the microchip’s circuits.
A passive tags read range is approximately
Containing characteristics of both active &
As far as their writing capability is
concerned, tags can be divided as follows :
Read only tag
Write once read many tag
Read & write tag
Read-only contain data such as tracking
These tracking numbers are usually serialized
and pre-written onto them by the tag
Read-only tags are usually the least expensive
because information can not be added onto
them as they move through the supply chain.
Write-once tags allow a user to write
information into the tag one time during the
production. The information can be something
like a batch or serial number.
Full read-write tags allow for new data to be
written to the tag as it is needed. These tags
also allow for original data to be written over.
allow a user to write information into the tag
many time during the production.
The antenna emits radio signals to activate the
tag and to read and write data into the tag.
The antenna is the channel between the tag and
the transceiver, thus it controls the data
attainment and communication.
The antennas are available in many different
shapes and sizes. For example an antenna can
be built into a doorframe in order to collect
data from people walking through the door.
The reader releases radio waves in ranges from
one inch to 100 feet or more. The range depends
on its output power and the radio frequency used.
When the RFID tag passes through the
electromagnetic field it will then detect the
reader’s activation signal.
At this point the reader will decode the data
programmed in the tag’s circuit.
Finally, the data is passed to the host computer to
Retail Supply chain process
Supplier Manufacturing Retailer/
Automate the Supply chain process
Non-line of sight identification of tags
Unattended operations are possible, minimizing
human errors and high cost.
RFID technology is better than bar codes as it cannot
be easily replicated and therefore, it increases the
security of the product.
Ability to identify moving elements that have tags
Larger area of coverage, up to several feet.
Expensive compared with Bar code
Bulkier, due to embedding of electronic
components in the tag. However, with advanced
techniques, it is possible to reduce the size, and
weight of the tags to a large extent.
It is difficult for an RFID reader to read the
information in case of RFID tags installed in
liquids and metal products. The problem is that
the liquid and metal surfaces tend to reflect the
radio waves, which makes the tags unreadable
To physical/electrical damage due to
RFID Chain management is an emerging
If efficiently implemented, RFID has the
power to make computing an unobtrusive,
intuitive part of everyday life.