|
An RFID Primer
There are four different kinds of tags commonly in use, their differences based on the level of their radio frequency: Low frequency tags (between 125 to 134 kilohertz), High frequency tags (13.56 megahertz), UHF tags (868 to 956 megahertz), and Microwave tags (2.45 gigahertz).
Current usage
Low-frequency RFID tags are commonly used for animal identification, beer keg tracking, and automobile key-and-lock, anti-theft systems. Pets are often embedded with small chips so that they may be returned to their owners if lost. In the United States, two RFID frequencies are used: 125kHz (the original standard) and 134.5kHz, the international standard.
High-frequency RFID tags are used in library book or bookstore tracking, pallet tracking, building access control, airline baggage tracking, and apparel item tracking. High-frequency tags are widely used in identification badges, replacing earlier magnetic stripe cards. These badges need only be held within a certain distance of the reader to authenticate the holder.
UHF RFID tags are commonly used commercially in pallet and container tracking, and truck and trailer tracking in shipping yards.
Microwave RFID tags are used in long-range access control for vehicles, an example being General Motors' OnStar system.
Some toll booths, such as California's FasTrak system, use RFID tags for electronic toll collection. The tags are read as vehicles pass; the information is used to debit the toll from a prepaid account. The system helps to speed traffic through toll plazas.
Sensors such as seismic sensors may be read using RFID transceivers, greatly simplifying remote data collection.
In January 2003, Michelin announced that it has begun testing RFID transponders embedded into tires. After a testing period that is expected to last 18 months, the manufacturer will offer RFID-enabled tires to carmakers. Their primary purpose is tire tracking in compliance with the United States Transportation, Recall, Enhancement, Accountability, and Documentation Act (TREAD Act).
|