RFID (Radio Frequency Identification) tags

Soon UPC (Universal Product Codes) labels and bar-codes are going to disappear from products and boxes and will be replaced by RFID (Radio Frequency Identification) tags . Supply chain management, Automatic identification and data capture and Asset management industries have decided to embrace RFID in a big way. The trends in RFID adoption rate shows that everyone from DOD (US Department of Defense) to Wal-Mart to Blood banks are implementing RFID. The technology used in RFID has been around since mid 1940. RFID tags are essentially Integrated Circuits (ICs) with a Antenna, Transmitter and EEPROM for data storage. Passive RFID tags are powered by minute electrical current induced in the antenna by the incoming radio frequency signal which provides just enough power for the CMOS integrated circuit in the tag to power up and transmit a response. While the active ones have their own power source and have ranges up to few hundred meters and battery life up to 10 years.
These RFID tags operate in varied frequency ranges from Low-frequency (LF: 125 - 134.2 kHz and 140 - 148.5 kHz) to high-frequency (HF: 13.56 MHz) and can be used globally without a license. Some countries are using Ultra-high-frequency (UHF: 868 MHz-928 MHz) though it cannot be used globally as there is no single global standard for it's use right now. In North America, UHF can be used in unlicensed for 902 - 928 MHz (+/-13 MHz from the 915 MHz center frequency), but restrictions exist for transmission power. Right now a lot of debate is going on the merits and demerits of which frequency band-- high frequency (HF) or ultrahigh frequency (UHF) is best for deployment of RFID at item-level. But either way RFID is going to be here. An early settlement of this issue will definitely speed up the deployment.

Cloning of RFID tags and readability by unauthorized sources are the major security concerns.These are being addressed by cryptographic protocols and encryption schemes.








An EPC RFID tag used for Wal-Mart.
More info at
http://www.rfidjournal.com/