Radio Frequency Identification (RFID): Definitions

(some of the of terms used in RFID technology)

Capable of operating (not simultaneously) in either of two directions that are the opposite of each another.
A numbering system in which numbers are expressed as combinations of digits "0" and "1" or "off" and "on".
The number of bits that can be programmed into the RFID tag.
capture window
Region of the scanner field in which a tag will operate.
carrier frequency
The main frequency of a transmitter, or RFID reader; such as, 915 MHz. The frequency is then changed, or modulated, to transmit information.
An RFID tag that doesn't depend on a silicon microchip.

Some chipless tags use plastic or conductive polymers instead of silicon-based microchips. Other chipless tags use materials that reflect back a portion of the radio waves beamed at them.

A computer takes a snapshot of the waves beamed back and uses it like a fingerprint to identify the object with the tag.

Companies are experimenting with embedding RF reflecting fibers in paper to prevent unauthorized photocopying of certain documents. Chipless tags that use embedded fibers have one drawback for supply chain uses: only one tag can be read at a time.

circular-polarized antenna
A UHF reader that emits radio waves in a circular pattern.

These antennas are used in situations where the orientation of the tag to the reader cannot be controlled.

Since the waves are moving in a circular pattern, they have a better chance of hitting the antenna, but circular-polarized antennas have a shorter "read range" than linear-polarized antennas.

closed-loop systems
RFID tracking systems set up within a company. Since the tracked item never leaves the company's control, it does not need to worry about using technology based on open standards.
A device connected to several RFID readers to gather data from the readers.

The concentrator usually performs some filtering and then passes only useful information from the readers on to a host computer.

contactless-smart card (s) (noun), contactless-smart cards (pl)
1. An awkward name for a credit card or loyalty card that contains an RFID chip to transmit information to a reader without having to be swiped through a reader. Such cards can speed checkout; therefore, providing consumers with more convenience.
2. An identification card that contains an RFID chip to transmit information to a reader without having to be swiped through a reader.
cyclic redundancy check, CRC
A method of checking data stored on an RFID tag to be sure that it hasn't been corrupted or some of it lost.
data field (s) (noun), data fields (pl)
An area of memory on an RFID (Radio-frequency identification) microchip that is assigned to a particular type of information: Data fields may be protected or they may be written over, so a data field might contain information about where an item should be sent.
data field protection (s) (noun), data field protections (pl)
The ability to prevent data stored in a specific area of memory of an RFID (Radio-frequency identification) microchip from being overwritten: Some companies use the data field protection device to store an Electronic Product Code, which doesn't change during the life of the product it's associated with.

data transfer rate (s) (noun), data transfer rates (pl)
The number of characters that can be moved from an RFID (Radio-Frequency Identification) tag to a reader within a given time: The measure of data transfer rate or the speed with which a computer device transmits information are also used to quantify how fast readers can read the information on the RFID tag.

Data transfer rate differs from the "read rate" which refers to how many tags can be read within a given period of time.

decibel, dB
A measure of the gain of an antenna.

See antenna gain for more information.

List of Radio Frequency Identification or RFID articles.