RFID (Radio Frequency Identification) technology is not new. In fact, it’s been around for decades but has recently enjoyed a surge of media coverage.
Unfortunately, media hyperbole has represented RFID as “the imminent replacement to barcode technology” and a panacea for all of the industry’s item tracking quandaries. RFID has the potential to be a world-changing technology, as it already is in applications such as pet and livestock identification and quick-payment systems (e.g. Esso’s Speedpass). But before plowing headlong into acquiring an RFID-based system, one should really know at least the following:
• RFID is an identification technology, not a finding technology. While RFID readers can be mounted in doorways and the like and can record what passed by them and entered a room at a specific time, they can’t tell you where exactly—or even approximately—in the room they’re located. A different RFID-based technology called an RTLS (Real-Time Locating System) employs many specialized networked RFID readers and uses RF-based triangulation to track objects to X and Y—and perhaps even Z—coordinates in real-time.
• An RFID transponder (“tag”) is primarily made up of an antenna, a chip, a battery (if it’s an active tag) and a “fixture” that houses the components that are specific to the application environment in which the tag will be used. A fixture can be made of paper or any one of many different synthetic materials.
• There are currently 50¢ (or less) RFID tags and there are tags that can be read from distances of 30m or more. The latter cost considerably more than half a dollar each! Generally speaking, the cost of the tags and readers is going to be commensurate with their performance.
• How are the RFID tags going to be mounted onto the things they’re identifying? It’s relatively easy to envision how they might be affixed to pallets, vehicles or documents — but just how are you going to put them on hand tools?
• A given RFID system employs any one of four different radio frequency ranges and the tags and readers must be matched — otherwise it’s like trying to get an AM radio station on your FM radio! Each frequency has its respective pros and cons, which involve aspects such as read range; immunity to metal, liquids and other solids; and tag size.
• Much RFID technology is proprietary in nature, so don’t necessarily expect Brand X’s readers to read the tags manufactured by Brand Y. This situation, through standardization, is becoming less significant. However, a given standard isn’t always the “best” for a given situation — especially if it’s extreme or unorthodox in nature. 
• Liquids and metals can adversely affect tag readability, potentially even making an RFID tag inoperable. Various tag application strategies (e.g. installing each tag offset from the metal application surface) and new technology is working to get around this scientific hurdle.
• Some RFID technologies allow multiple tags to be read simultaneously, perhaps as a cart or vehicle passes by a reader. Most expect a single read at a time.
• A lot of people initially want the longest read range possible and then realize that perhaps they don’t! Unlike our eyes or barcode scanners, RFID readers read in an almost spherical pattern. So, the thing your RFID reader is seemingly aimed at might also be reading numerous other RFID-enabled things in a given area — which might be in adjacent rooms!
• Active RFID tags have an internal battery that can broadcast their ID at significant distances. However, such tags are relatively expensive, comparatively large and will need to be replaced every few years.
• Passive RFID tags are comparatively economical, but have relatively short read ranges (i.e. typically less than a metre).
• Hybrid tags, which combine both passive and active elements, are becoming more common and have some significant advantages.
• Some RFID tags are read-only, having a factory-embedded serial number in them. Some are infinitely readable/writable and can have on-board memory to hold thousands of characters of data. Many tags can be written-to only once.
• The EPC (Electronic Product Code) is an emerging RFID-based technology that uniquely identifies and indicates everything about the thing it’s attached to. That is, it might not only identify a can of pop as a 355ml can of Coke, but also the fact that it was the 370th one produced in the Edmonton plant on the 31st of May, 2008!
• RFID tags can be read with fixed-in-place readers or mobile readers. Because mobile readers have significantly less electrical power at their disposal, expect them to have considerably shorter read ranges.
• Generally speaking, the bigger an RFID tag’s antenna is, the further away it can be read. So don’t expect a pea-sized tag to be readable from many meters away!
• The best ROI for RFID technology is currently in “closed loop” systems. That is, systems that you can design and use within your four walls or operations that don’t involve trading partners or other entities.
•  A significant application for RFID that’s commonly overlooked is product authentication. Industries based in everything from pharmaceuticals to sports memorabilia are adopting it.
 • Before an RFID-based system becomes an item or person tracking project, it must first be an engineering project. Plan on spending a lot of time and money researching and testing RFID technology in a given application environment before a full-scale system rollout. Using a knowledgeable RFID-experienced system developer and integrator will help you to determine a given application’s viability from the outset and ensure its technological success.
Ian W. Bowden is the Founder and President of Aurora Barcode Technologies Ltd., an Edmonton-based company which has provided barcode and RFID based system solutions to clients throughout North America for over two decades. He can be reached at 800.689.7696 x126 or ian.bowden@aurorabarcode.com.