Radio Frequency Identification (RFID) uses special data carriers, or tags, to hold data. Readers use RF signals to communicate with the tags.

System availability ranges from:

• Low frequency • Mid frequency • High frequency

Note that frequency ranges are relative terms -- with high simply signifying that it's above mid, and mid is above low.

Generally, range, data transfer rate (DTR), and the dampening effects of overlying materials increase with frequency. Absorption of signal by metal decreases with frequency.

Depending on the frequency and technology employed, system performance can range from:

• One-bit Electronic Article Surveilance tags to sophisticated read/write systems with up to 4K of addressable memory.
• Reading distances of only a few centimeters or up to 30 meters.
• Tag read stationary or at 100 kph or more.

RFID standards are now beginning to provide for open systems architecture. Standards have been developed, or are being developed for:

• Maritime container ID,
• Rail and truck rolling stock ID,
• Companion animal tagging,
• Manufacturing,
• Pallet and returnable container ID, and
• Lifetime product ID.

RFID systems are currently being used for:

• Electronic article surveillance (EAS),
• Intermodal container identification,
• Rail and truck rolling stock identification,
• Animal (livestock and domestic) identification,
• Automated livestock feeding stations,
• Flexible manufacturing (tracking and control),
• Cutting tool identification,
• Asset identification,
• Laundry tracking,
• Vehicle identification / access control, and
• Automated debit or credit cards (gasoline),
• Automated toll collection, and
• Personnel identification / access control.

RFID Advantages:

Great flexibility,
• Read/write capabilities or permanent (non-erasable) ID,
• Non-contact, non-line-of-sight reading,
• Virtual immunity from obscuring paint, dirt, grease, etc., (depending on frequency)
• Automatic operation,
• Low cost-per-use,
• Wide range of tag options,
• Range to 100 feet,
• Reading speeds to 60 mph,
• Extremely high data integrity, and
• Extremely difficult to counterfeit.

RFID Limitations:

• Initial cost of tags,
• Limited interchangeability of tags (at present -- soon to change), and
• Possibility of interference in operation by strong EMI from outside sources.