Radio Frequency Identification (RFID): Definitions
(some of the of terms used in RFID technology)
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.
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GTAG initiative was supported by Philips Semiconductors, Intermec, and Gemplus, three major RFID tag makers; but it was superseded by the Electronic Product Code.
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.
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.
Inlays are essentially unfinished RFID labels. They are usually sold to label converters who turn them into smart labels.
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.
The Auto-ID Center promoted the concept as a way to simplify the tag and reduce the cost.
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.