October 23, 2007

A beginners guide to RFID Technology and Systems

Look no further - this page gives you the simple explanation of Radio Frequency Identification (RF-ID or RFID) devices, what they are, how they work, why they are important, and why they can change your company's processes to drastically improve cost effectiveness and remove waste and lost revenue! There are also links to other useful information on the rfidXchange site.

RFID tags and readers have been available for many years - mainly low end passive security devices in stores, and powered active tags that have internal batteries to enable them to be read from a much greater distance. Such active items are usually expensive - over $20 per tag, and have a limited life of around 2-4 years.

The big change over the past 2 years has been the collaborative work - via the Auto-ID Center - of a number of companies and universities to develop the standards and designs for a new range of simple passive tags that can be manufactured in bulk and eventually reduce the cost per tag down to the 10c range. At the same time, this research work generated designs for simpler reader technology and for a global structure to enable a simple passive tag holding a serial number to be linked to the company database that holds the history and attributes of the specific item that the tag is attached to. This concept allows the tag to hold little more than a unique UPC number (albeit one that is specific to a unique item rather than a product type) with the complex changing information about that item held in remote databases. The readers that gather information for a tag will, in practice read that tag many times, and so a rationalization of the data is required. RFID Middleware, such as Savant, takes that role, and uses some of the bits from the tag to look-up, via a system of ONS servers, the location of the latest data on that tag. The data can be held in the original manufacturer's systems, or in databases belonging to the numerous companies that may have handled that item during its track through the supply chain. The integration of these various elements of data is what makes an full implementation complex but ultimately very rewarding.

Many companies are developing tags based on these new standards - at the time of writing, there are few final designs available in quantity although versions made against earlier standards are freely available. Tags and Readers to the new designs should be available in mid 2004.

Wal-Mart, Tesco and the US Department of Defense have, between them, created pressure on their key suppliers to tag incoming items with RFIDs in the early months of 2005. Initially, this will be at the pallet or case level, although high value individual items may be tagged shortly afterwards. Supplier companies can take the easy way out to simply attach tags and maintain a simple database to identify the item tagged - but this approach will leave many opportunities for internal improvements untouched. The sensible approach is to start as early as possible and review internal processes to maximize the benefits from the technology.

There are many issues in using RFIDs - each of which will need time and focus to resolve:

Tag choice and affixing method (some tags are not readable through liquids)
Reader/Tag interaction - acceptable reading distances can be up to 2m (7 feet)
Antenna design and spacing - where are the antennas in relation to the package
Rate of movement and quantity of tags - readers use special anti-collision software to identify different tags in their viewing area
Choice of Middleware - the software used to manage the flow of data from readers and integrate with back-end systems
Integration into the Global EPC database structure, using open source systems such as Savant to link to the "home" database for the product
Integration into existing back-end management and inventory systems
Sheer quantity of data if every item is tagged - puts pressure on databases and network components