What is RFID?

Prepare to deal with this emerging technology

Radio frequency identification (RFID) technology is finding wide application in a variety of industries. Electrical contracting firms need to be aware of this new technology and how its customers can use it. Below you will find an introduction to RFID and a discussion of current and future RFID applications.

RFID technology uses radio frequency signals to transfer data from an RFID tag on a product to an RFID reader. RFID tags are tiny microchips that transmit information in response to a query from a reader. Passive RFID tags consist only of a microchip and antenna and do not need a separate power source, so they can be very small. The power in the RFID reader’s radio frequency (RF) query is used to activate the passive RFID tag and enables the tag to send its response back to the reader. As a result, passive RFID tags do not have a shelf life like a battery-operated transponder would and will operate indefinitely.

Passive RFID tags can be read at a distance of about 15 feet under ideal conditions. The passive RFID tag distance limitation can be overcome by using active RFID technology or “smart labels” that require batteries, which limits their useful life and increases their cost, but increases their signal strength and allows them to be read at distances of about 30 feet. The price of passive RFID tags is dropping as the technology to produce them improves and the quantity demanded increases. This means that passive RFID tags will find more and more applications in the future and RFID is a rapidly emerging technology to watch.

RFID tags can be encoded with all sorts of information that can be useful in a wide variety of industries. In retailing, RFID technology can help stores track inventory, avoid stock outs and reduce loss due to spoilage and theft. “Smart shelves” in tomorrow’s retail stores will be able to track how much product is on the shelf at any time and know when a customer takes product off the shelf. It is possible that in the future, customers will be checked out automatically by an RFID reader as they leave the store, which will identify what they have bought, know who they are through an RFID tag embedded in the credit or debit card, and automatically execute the transaction without the customer going through a traditional checkout stand.

RFID can help streamline the entire supply chain from manufacturer to consumer. With RFID technology, products can be tracked through the entire supply chain with minimal human intervention. Unlike bar codes that need to be scanned, RFID tags can be detected and read at short distances without actually having physical access to the printed bar code. This can reduce warehouse and distribution labor costs as well as improve the reliability and timeliness of warehousing and shipping information. Wal-Mart is requiring its top 100 suppliers to put RFID tags on their pallets and cases by Jan. 1, 2005. Similarly, the Department of Defense (DOD) is requiring suppliers to put RFID tags on its shipments by 2005.

To illustrate the wide range of applications that RFID technology will have, consider the development of iGlassware by Mitsubishi Electric Research Laboratories (MERL, www.merl.com). MERL has developed wireless liquid level-sensing glassware for restaurants. iGlassware uses capacitance to sense the liquid level in the glass and then transmits that information using RFID technology through a coil embedded in the table. Each glass has its own ID, iGlassware does not look any different than “dumb” glasses, and iGlassware is dishwasher safe. MERL believes that iGlassware will help restaurants better serve their customers as well as increase profits by selling more drinks.

RFID could emerge as a valuable technology for the electrical contractor as well. For instance, passive RFID tags could be attached to your small tools and equipment, which could improve tracking and reduce costs due to loss and theft. Similarly, materials and equipment delivered and installed at the job site could be more easily tracked and inventoried using RFID technology. Problems resulting from damaged or missing labels and bar codes at the job site would be eliminated because RFID tags would be permanently attached to the material or equipment and not as susceptible to damage. EC

This article is the result of an ongoing research project investigating the future of the VDV market that is sponsored by the Electrical Contracting Foundation, Inc. The author would like to thank the Foundation for its continuing support.

GLAVINICH is an associate professor in the Department of Civil, Environmental and Architectural Engineering at The University of Kansas and is a frequent instructor for NECA’s Management Education Institute. He can be reached at 785.864.3435 or tglavinich@ku.edu.


About the Author

Thomas E. Glavinich

Freelance Writer
Thomas E. Glavinich was an associate professor in the Department of Civil, Environmental and Architectural Engineering at the University of Kansas. His tenure as one of Electrical Contractor's most trusted and reliable source of industry research end...

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