RFID Solution Provided by Indian Barcode Corporation (A unit of Mindware )
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 serves
the same 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. And, 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.
How RFID Works
- A scanning antenna
- A transceiver with a decoder to interpret the data
- A transponder - the RFID tag - that has been programmed with information.
- It provides a means of communicating with the transponder (the RFID tag) AND
- It provides the RFID tag with the energy to communicate (in the case of passive RFID tags).
- The tag need not be on the surface of the object (and is therefore not subject to wear)
- The read time is typically less than 100 milliseconds
- Large numbers of tags can be read at once rather than item by item.
How does RFID work?
A Radio-Frequency IDentification system has
three parts:
The
scanning antenna puts out radio-frequency signals in a relatively short range.
The RF radiation does two things:
This is
an absolutely key part of the technology; RFID tags do not need to contain
batteries, and can therefore remain usable for very long periods of time (maybe
decades).
The scanning antennas can be permanently affixed to a
surface; handheld antennas are also available. They can take whatever shape you
need; for example, you could build them into a door frame to accept data from
persons or objects passing through.
When an RFID tag passes through the field of the scanning
antenna, it detects the activation signal from the antenna. That "wakes
up" the RFID chip, and it transmits the information on its microchip to be
picked up by the scanning antenna.
In addition, the RFID tag may be of one of two types. Active
RFID tags have their own power source; the advantage of these tags is that
the reader can be much farther away and still get the signal. Even though some
of these devices are built to have up to a 10 year life span, they have limited
life spans. Passive RFID tags, however, do not require batteries, and can
be much smaller and have a virtually unlimited life span.
RFID tags can be read in a wide variety of circumstances,
where barcodes or other optically read technologies are useless.
Frequency
Rang
Low Frequency (LF)
|
High Frequency (HF)
|
Ultra High Frequency (UHF)
|
125kHz, 134.2kHz
|
13.56 MHz (Global)
|
865 – 928 MHz (Regionally dependent)
|
1.Low-frequency tags have
a long wave-length and are better able to penetrate thin metallic substances.
Additionally, LF RFID systems are ideal for reading objects with
high-water content, such as fruit or beverages, but the read range is limited
to centimeters or inches. Typical LF RFID applications include access control
and animal tagging.
2.High-frequency tags work
fairly well on objects made of metal and can work around goods with medium to
high water content. Typically, HF RFID systems work in ranges of inches,
but they can have a maximum read range of about three feet (1 meter).
Typical HF RFID applications include tracking library books, patient flow
tracking, and transit tickets.
3.UHF frequencies typically
offer much better read range (inches to 50+ ft. depending on the RFID
system setup) and can transfer data faster (i.e. read many more tags per
second) than low- and high-frequencies. However, because UHF radio
waves have a shorter wavelength, their signal is more likely to be attenuated
(or weakened) and they cannot pass through metal or water. Due
to their high data transfer rate, UHF
RFID tags are well suited for many items at
once, such as boxes of goods as they pass through a dock door into a
warehouse or racers as they cross a finish line. Also, due to the longer
read range, other common UHF RFID applications include electronic toll
collection and parking access control.
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