What is RFID?

Short for radio frequency identification, RFID is a dedicated short range communication (DSRC) technology. The term RFID is used to describe various technologies that use radio waves to automatically identify people or objects. RFID technology is similar to the bar code identification systems we see in retail stores everyday; however one big difference between RFID and bar code technology is that RFID does not rely on the line-of-sight reading that bar code scanning requires

The Technology Behind RFID
With RFID, the electromagnetic or electrostatic coupling in the RF (radio frequency) portion of the electromagnetic spectrum is used to transmit signals. An RFID system consists of an antenna and a transceiver, which read the radio frequency and transfer the information to a processing device (reader) and a transponder, or RF tag, which contains the RF circuitry and information to be transmitted. The antenna provides the means for the integrated circuit to transmit its information to the reader that converts the radio waves reflected back from the RFID tag into digital information that can then be passed on to computers that can analyze the data.

In RFID systems, the tags that hold the data are broken down into two different types. Passive tags use the radio frequency from the reader to transmit their signal. Passive tags will generally have their data permanently burned into the tag when it is made, although some can be rewritten.

Active tags are much more sophisticated and have on-board battery for power to transmit their data signal over a greater distance and power random access memory (RAM) giving them the ability to store up to 32,000 bytes of data.

RFID Frequencies
Much like tuning in to your favorite radio station, RFID tags and readers must be tuned into the same frequency to enable communications. RFID systems can use a variety of frequencies to communicate, but because radio waves work and act differently at different frequencies, a frequency for a specific RFID system is often dependant on its application. High frequency RFID systems (850 MHz to 950 MHz and 2.4 GHz to 2.5 GHz) offer transmission ranges of more than 90 feet, although wavelengths in the 2.4 GHz range are absorbed by water, which includes the human body, and therefore has limitations.

Common Uses of RFID
RFID systems can be used just about anywhere, from clothing tags to missiles to pet tags to food - anywhere that a unique identification system is needed. The tag can carry information as simple as a pet owners name and address or the cleaning instruction on a sweater to as complex as instructions on how to assemble a car.

Here are a few examples of how RFID technology is being used in everyday places:

• RFID systems are being used in some hospitals to track a patient's location, and to provide real-time tracking of the location of doctors and nurses in the hospital. In addition, the system can be used to track the whereabouts of expensive and critical equipment, and even to control access to drugs, pediatrics, and other areas of the hospital that are considered "restricted access" areas.
  
  
  
• RFID chips for animals are extremely small devices injected via syringe under skin. Under a government initiative to control rabies, all Portuguese dogs must be RFID tagged by 2007. When scanned the tag can provide information relevant to the dog's history and its owner's information.
  
  
  
• RFID in retail stores offer real-time inventory tracking that allows companies to monitor and control inventory supply at all times.
  
  
  
• The Orlando/Orange County Expressway Authority (OOCEA) is using an RFID based traffic-monitoring system, which uses roadside RFID readers to collect signals from transponders that are installed in about 1 million E-Pass and SunPass customer vehicles.

The Future of RFID
RFID is said by many in the industry to be the frontrunner technology for automatic identification and data collection. The biggest, as of yet unproven, benefit would ultimately be in the consumer goods supply chain where an RFID tag attached to a consumer product could be tracked from manufacturing to the retail store right to the consumer's home.

Many see RFID as a technology in its infancy with an untapped potential. While we may talk of its existence and the amazing ways in which this technology can be put to use, until there are more standards set within the industry and the cost of RFID technology comes down we won't see RFID systems reaching near their full potential anytime soon.