Radio Frequency Identification (RFID): Definitions

(some of the of terms used in RFID technology)

frequency hopping
A technique used to prevent readers from interfering with one another.

In the United States, UHF RFID readers actually operate between 902 and 928 MHz, even though it is said that they operate at 915 MHz.

The readers may jump randomly or in a programmed sequence to any frequency between 902 MHz and 928 MHz.

If the band is wide enough, the chances of two readers operating at exactly the same frequency is small.

The UHF bands in Europe and Japan are much smaller so this technique is not effective for preventing reader interference.

global tag, GTAG
A standardization initiative of the Uniform Code Council (UCC) and the European Article Numbering Association (EAN) for asset tracking and logistics based on radio frequency identification (RFID).

The GTAG initiative was supported by Philips Semiconductors, Intermec, and Gemplus, three major RFID tag makers; but it was superseded by the Electronic Product Code.

A term sometimes used to describe the way passive tags gather energy from an RFID reader antenna.
high-frequency tags
1. From three MHz to 30 MHz. HF RFID tags typically operate at 13.56 MHz.

They typically can be read from less than three feet away and transmit data faster than low-frequency tags, but they consume more power than low-frequency tags.

2. Tags that operate between three and 30 MHz.

The frequency used in library RFID systems is 13.56 MHz. ISO 18000-3 addresses the air interface for tags operating in this frequency range.

These tags can be read at up to a distance of ten feet and have a fast data transfer rate.

ID filter
Software that compares a newly read ID with that in a database.
inductive coupling
A method of transmitting data between tags and readers in which the antenna from the reader picks up changes in the tag’s antenna.
An RFID microchip attached to an antenna and mounted on a substrate.

Inlays are essentially unfinished RFID labels. They are usually sold to label converters who turn them into smart labels.

input/output, I/O
Ports on a reader.

Users can connect devices; such as, an electronic eye to the input port so that when an object breaks the beam of the electronic eye the reader begins reading.

Devices can also be connected to an output part, so that when a tag is read, a conveyor is turned on or a dock door opened.

integrated circuit, IC
A microelectronic semiconductor device comprising many interconnected transistors and other components. Most RFID tags have ICs.
An electronic interconnection of devices; whether hardware or software.
An RFID reader. See Reader for more info.
in-use programming
The ability to write data to a tag while it is attached to its object.
ISO 18000-3
The pending standard for the air interface for RFID tags that operate at 13.56 MHz.
licence plate
This term generally applies to a simple RFID that has only a serial number that is associated with information in a database.

The Auto-ID Center promoted the concept as a way to simplify the tag and reduce the cost.

linear-polarized antenna
A UHF antenna that focuses the radio energy from the reader in a narrow beam.

This increases the read distance possible and provides greater penetration through dense materials.

Tags designed to be used with a linear polarized reader antenna must be aligned with the reader antenna in order to be read.

List of Radio Frequency Identification or RFID articles.