Radio Frequency Identification (RFID)

Background

RFID refers to technologies that utilize radio waves to automatically identify individual objects. It allows information to be collected automatically without human contact or intervention. An RFID 'system' consists of an interrogator (reader) and a 'tag' (transponder). The reader generates an electromagnetic field; upon entering the electromagnetic field, the tag becomes active, turning on its own transmitter, allowing it to respond to the interrogation from the reader. The reader accepts the data from the tag and transmits the information to a computer for further processing.

RFID technology plays a vital role in DoD by providing an end-to-end supply chain to the warfighter using a fully automated suite of technologies. The Department's goal is to continue to collect data in a hands-free, non-intrusive environment to the maximum extent possible. RFID is an enabling technology that effectively addresses the long-standing problem of tracking material at crucial nodes throughout the full distribution pipeline. It is viewed as an opportunity to track assets in a variety of functional circumstances: locating assets stored in a warehouse, conducting inventories, or tracking material flowing through a maintenance operation. Most importantly, RFID's major contribution is seen as tracking material from its point of origin to the last tactical mile.

Not a Standalone, 'Silver Bullet' Solution

RFID technology is capable of supporting the requirements for a more flexible agile force, but it is not to be used in isolation. As numerous lessons-learn indicate, RFID technology must be more fully incorporated and integrated into current DoD business practices as an enabling tool, not a replacement for current way of doing business. 

Differences Between Active and Passive Tags

RFID tags that contain their own power source are known as active tags. Those without a power source are known as passive tags. A passive tag is briefly activated by the radio frequency scan of the reader. The electrical current is small -- generally just enough for transmission of an ID number. Active tags have more memory and can be read at greater ranges. Active tagging has already earned a well-deserved reputation for improving DoD’s capability for tracking material thru the supply chain. Adding the advantage of passive RFID technology will only create greater efficiency and data accuracy. In application, active RFID is used to tag freight containers and air transport pallets, whereas passive RFID is used to tag individual cases and pallet loads. Increasingly, RFID tagging is used in supply chain management as an alternative to the more familiar and far older bar code technology. Although more expensive to use than the bar code stickers, RFID tags don't get dirty, they don’t fall off, and they don’t require an unobstructed line-of-sight between the tag and the reader. There are almost endless possible uses for RFID tagging.

DoD uses both classes of tags as long as they adhere to one of two standard constructs: the Electronic Product Code Global (EPCglobal) construct, or the DoD construct in accordance with MIL-STD-129R:  DoD Standard Practice, Military Marking for Shipment and Storage. 

Connection Between Barcode and RFID Technology

People often ask what the distinctions are between barcode and RFID technolog, and it can be summarized as follows:

• RFID supplements, but does not replace, barcodes. RFID is simply another method of identifying material. 
• Barcodes 'see' the material, while an RFID tag can 'hears' the material. This means that while a barcode must be physically viewed by a scanner, RFID technology permits material to pass by a given point at a fairly high rate of speed and read a label reliably that is up to 25 feet away.
• A big advantage of RFID over barcode technology is that it prevents duplication errors.
  • Each RFID tag is identified with a unique serial number, and it is one of a kind – very much like its sister technology, Item Unique Identification (IUID).

IUID and RFID

There is often confusion regarding the relationship between IUID and RFID. They share a common bond in that they both generate one of a kind serial numbers, but beyond that they part company. Differences include the following:

• An IUID mark identifies individual items that warrant a unique identifier, whereas an RFID tag can identify all individual packages in transit.
• IUID is a business-oriented concept whereas RFID is a logistics-oriented concept.
  • IUID is, in part, dollar driven; RFID is not.
    • In general, an item will not be marked with an IUID stamp unless it meets a minimum threshold of $5,000 in value, although there are exceptions to this general rule.
    • When using an RFID tag, all DoD materiel that is destined for the military supply pipeline can be tagged with an RFID chip,regardless of dollar value.
• The technologies differ greatly in the manner in which their respective “marks” are read.
  • An IUID mark is read like a standard barcode, i.e, the reader must be in close physical proximitly
  • An RFID tag can be read at a distance.

For more information on RFID, please refer the the list below as well as the Office of the Assistant Secretary of Defense for Sustainment (OASD(S)) RFID Supplier Info and FAQ webpage and the United States Department of Defense Suppliers’ Passive RFID Information Guide. Also see United States Transportation Command (ustranscom.mil).